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Document and Entity Information - USD ($)	12 Months Ended
Document and Entity Information - USD ($)	Dec. 31, 2015	Mar. 11, 2016	Jun. 30, 2015
Document And Entity Information [Abstract]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2015
Document Fiscal Year Focus	2015
Document Fiscal Period Focus	FY
Trading Symbol	KURA
Entity Registrant Name	Kura Oncology, Inc.
Entity Central Index Key	0001422143
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	No
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Filer Category	Smaller Reporting Company
Entity Public Float			$ 0
Entity Common Stock, Shares Outstanding		21,370,560

BALANCE SHEETS - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Current assets:
Cash and cash equivalents	$ 15,443	$ 1,124
Short-term investments	70,303
Accounts receivable, related party	430	30
Prepaid expenses and other current assets	693	42
Total current assets	86,869	1,196
Property and equipment, net	71	27
Other long-term assets	314	150
Other long-term assets, related party	5	5
Total assets	87,259	1,378
Current liabilities:
Accounts payable and accrued expenses	4,118	846
Accounts payable and accrued expenses, related party	937	134
Convertible notes payable, related party, current		2,036
Total current liabilities	5,055	3,016
Convertible notes payable, related party		493
Other long-term liabilities	101	1,295
Other long-term liabilities, related party		7
Total liabilities	5,156	4,811
Commitments and contingencies (Note 10)
Stockholders' equity (deficit):
Preferred stock, $0.0001 par value; 10,000 shares authorized; no shares issued and outstanding
Common stock, $0.0001 par value; 200,000 and 100,000 shares authorized; 21,371 and 4,944 shares issued; and 18,138 and 411 shares outstanding, excluding 3,233 and 4,533 shares subject to repurchase as of December 31, 2015 and December 31, 2014, respectively	2
Additional paid-in capital	108,484	238
Accumulated comprehensive loss	(87)
Accumulated deficit	(26,296)	(3,671)
Total stockholders' equity (deficit)	82,103	(3,433)
Total liabilities and stockholders' equity (deficit)	$ 87,259	$ 1,378

BALANCE SHEETS (Parenthetical) - $ / shares	Dec. 31, 2015	Dec. 31, 2014
Statement Of Financial Position [Abstract]
Preferred stock, par value	$ 0.0001	$ 0.0001
Preferred stock, shares authorized	10,000,000	10,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value	$ 0.0001	$ 0.0001
Common stock, shares authorized	200,000,000	100,000,000
Common stock, shares issued	21,371,000	4,944,000
Common stock, shares outstanding	18,138,000	411,000
Number of shares, subject to repurchase	3,232,350	4,533,000

STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS - USD ($) shares in Thousands, $ in Thousands	4 Months Ended	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2015
Operating Expenses:
Research and development	$ 2,028	$ 13,905
Research and development, related party	624	3,872
General and administrative	1,262	6,019
General and administrative, related party	20	69
Total operating expenses	3,934	23,865
Other Income (Expense):
Management fee income, related party	300	1,200
Interest income		128
Interest expense	(37)	(42)
Interest expense, related party		(46)
Total other income	263	1,240
Net loss	$ (3,671)	$ (22,625)
Net loss per share, basic and diluted	$ (25.98)	$ (2.28)
Weighted-average number of shares used in computing net loss per share, basic and diluted	141	9,933
Comprehensive Loss:
Net loss	$ (3,671)	$ (22,625)
Unrealized loss on marketable securities		(87)
Comprehensive loss	$ (3,671)	$ (22,712)

STATEMENTS OF STOCKHOLDERS' EQUITY (DEFICIT) - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock	Additional Paid- In Capital	Unrealized Loss	Accumulated Deficit
Beginning balance at Aug. 21, 2014	$ 0	$ 0	$ 0	$ 0	$ 0
Share-based compensation expense	237		237
Restricted stock awards vested	1		1
Restricted stock awards vested (in shares)		411
Net loss	(3,671)				(3,671)
Ending balance at Dec. 31, 2014	(3,433)		238		(3,671)
Ending balance (in shares) at Dec. 31, 2014		411
Issuance of common stock for license fee	97,870	$ 2	97,868
Issuance of common stock for license fee, ( in shares)		15,164
Conversion of notes payable and accrued interest	7,615		7,615
Conversion of notes payable and accrued interest (in shares)		1,205
Share-based compensation expense	2,259		2,259
Restricted stock awards vested	4		4
Restricted stock awards vested (in shares)		1,279
Unrealized loss on marketable securities	(87)			(87)
Net loss	(22,625)				(22,625)
Ending balance at Dec. 31, 2015	82,103	$ 2	108,484	$ (87)	$ (26,296)
Ending balance (in shares) at Dec. 31, 2015		18,138
Issuance of common stock, net of offering costs	97,870	$ 2	97,868
Issuance of common stock for license fee	$ 500		$ 500
Issuance of common stock for license fee, ( in shares)		79

STATEMENTS OF CASH FLOWS - USD ($)
$ in Thousands

4 Months Ended

12 Months Ended

Dec. 31, 2014

Dec. 31, 2015

Operating Activities

Net loss

$ (3,671)

$ (22,625)

Adjustments to reconcile net loss to net cash used in operating activities:

Share-based compensation expense

237

2,259

Non-cash license fee expense

500

Change in value of derivative liability

^[1]

268

Non-cash accrued interest expense

Non-cash accrued interest expense, related party

Depreciation expense

Amortization of discount on marketable securities

171

Changes in operating assets and liabilities:

Accounts receivable, related party

(30)

(400)

Prepaid expenses and other current assets

(42)

(650)

Other long-term assets

(150)

(164)

Other long-term assets, related party

(5)

Accounts payable and accrued expenses

833

2,812

Accounts payable and accrued expenses, related party

135

803

Accrued interest, related party

Other long-term liabilities

1,307

(998)

Net cash used in operating activities

(849)

(17,925)

Investing Activities

Purchases of marketable securities

(76,562)

Maturities of marketable securities

6,000

Purchases of property and equipment

(28)

(64)

Net cash used in investing activities

(28)

(70,626)

Financing Activities

Proceeds from issuance of common stock, net

97,870

Proceeds from issuance of convertible notes

4,290

Proceeds from issuance of convertible notes, related party

2,000

710

Proceeds from issuance of restricted stock awards

Net cash provided by financing activities

2,001

102,870

Net increase in cash and cash equivalents

1,124

14,319

Cash and cash equivalents at beginning of period

1,124

Cash and cash equivalents at end of period

$ 1,124

15,443

Supplemental disclosure of non-cash financing activities:

Conversion of convertible notes and related accrued interest to common stock

4,327

Conversion of convertible notes and related accrued interest to common stock, related party

$ 3,288

[1]	The amount is included in research and development expenses on the statements of operations and comprehensive loss.

Organization and Basis of Presentation	12 Months Ended
Organization and Basis of Presentation	Dec. 31, 2015
Accounting Policies [Abstract]
Organization and Basis of Presentation	1. Organization and Basis of Presentation Kura Oncology, Inc., is a clinical stage biopharmaceutical company discovering and developing personalized therapeutics for the treatment of solid tumors and blood cancers. We focus on the development of small molecule product candidates that target cell signaling pathways that are important to driving the progression of certain cancers. We aim to employ molecular diagnostics to identify patients with cancers who are likely to benefit from our targeted product candidates. References in these Notes to Financial Statements to the “Company” or “we”, “our” or “us”, refer to Kura Oncology, Inc., or Prior Kura, a private Delaware corporation incorporated in the State of Delaware in August 2014, for the periods prior to the Merger (as defined below) which took place on March 6, 2015, and Kura Oncology, Inc., a Delaware corporation incorporated in November 2007 and formerly known as Zeta Acquisition Corp. III, or Zeta, a public shell company, for the periods following the Merger. Effective March 6, 2015, or the Effective Time, we completed a reverse merger, or the Merger, with a wholly owned subsidiary of Zeta, leaving Prior Kura as the surviving entity. On March 31, 2015, the surviving entity merged with and into us. Zeta was formed in November 2007 with no specific business plan or purpose. As a result of the Merger and related transactions, Zeta changed its name to “Kura Oncology, Inc.” and began operating Prior Kura’s business. Pursuant to the terms of an Agreement and Plan of Merger dated March 6, 2015, by and among Zeta, Kura Operations, Inc. and Prior Kura, at the Effective Time, each share of Prior Kura common stock outstanding immediately prior to the Effective Time was exchanged for one-half (0.5) of a share of our common stock. We issued an aggregate of 14,508,177 shares of our common stock upon such exchange of the Prior Kura common stock outstanding. In addition, at the Effective Time, we assumed Prior Kura’s 2014 Equity Incentive Plan that was in existence immediately prior to the Effective Time and concurrently approved the amendment and restatement of the Prior Kura 2014 Equity Incentive Plan, pursuant to our Amended and Restated 2014 Equity Incentive Plan, or 2014 Plan, which became effective in April 2015. Refer to Note 12, Equity Incentive Plan for detailed discussion of the 2014 Plan. Immediately following the Effective Time, pursuant to the terms of a Redemption Agreement dated March 6, 2015, by and among Zeta and its pre-Merger stockholders, we completed the closing of a redemption of 5,000,000 shares of our common stock, or the Redemption, from our pre-Merger stockholders for consideration of $70,000, plus $30,000 in professional fees related to the transaction. The 5,000,000 shares constituted all of the issued and outstanding shares of Zeta’s capital stock, on a fully-diluted basis, immediately prior to the Merger. Upon completion of the Merger and the Redemption, Prior Kura’s stockholders held 100% of the outstanding shares of our capital stock. The Merger was accounted for as a reverse merger and a capital transaction. Prior Kura is the acquirer for accounting purposes and Zeta is the acquired company. Consequently, the assets and liabilities and the operations that are reflected in the historical financial statements prior to the Merger are those of Prior Kura and are recorded at Prior Kura’s historical cost basis. Prior Kura was incorporated in August 2014; therefore, there were no operations in the periods prior to August 2014. The financial statements after completion of the Merger include our assets, liabilities and operations. The historical equity accounts and awards of Prior Kura, including par value per share, share and per share numbers, have been retrospectively adjusted to reflect the one for 0.5 shares common stock exchange, the par value of $0.0001 and the number of shares received in the Merger. Immediately prior to the Merger, on March 6, 2015, Prior Kura sold to investors 9,485,566 shares of its common stock at a price of $6.32 per share, or Private Placement, for net proceeds of approximately $55.8 million, which included approximately $7.5 million in principal and $115,000 in accrued interest from the conversion of the then outstanding convertible promissory notes. In November 2015, we completed a public offering in which we sold an aggregate of 6,883,467 shares of common stock at a price of $8.00 per share. Net proceeds from the public offering, after deducting underwriting discounts, commissions and offering expenses, were approximately $50.3 million.

Summary of Significant Accounting Policies

12 Months Ended

Dec. 31, 2015

Accounting Policies [Abstract]

Summary of Significant Accounting Policies

2. Summary of Significant Accounting Policies

Use of Estimates

Our financial statements are prepared in accordance with accounting principles generally accepted in the United States. The preparation of our financial statements requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of expenses during the reporting period.

Reported amounts and note disclosures reflect the overall economic conditions that are most likely to occur and anticipated measures management intends to take. Actual results could differ materially from those estimates. All revisions to accounting estimates are recognized in the period in which the estimates are revised and in any future periods affected.

Segment Reporting

Operating segments are identified as components of an enterprise about which separate discrete financial information is available for evaluation by the chief operating decision-maker in making decisions regarding resource allocation and assessing performance. We operate in a single industry segment which is the discovery and development of personalized therapeutics for the treatment of solid tumors and blood cancers. Our chief operating decision-maker reviews the operating results on an aggregate basis and manages the operations as a single operating segment.

Cash and Cash Equivalents

Cash equivalents consist of highly liquid investments that are readily convertible to cash and that mature within three months or less from the date of purchase. The carrying amounts approximate fair value due to the short maturities of these instruments. Cash and cash equivalents consist primarily of cash in readily available checking and money market accounts.

Short-Term Investments

Short-term investments are marketable securities with maturities greater than three months from date of purchase that are specifically identified to fund current operations. These investments are classified as current assets, even though the stated maturity date may be one year or more beyond the current balance sheet date, which reflects management’s intention to use the proceeds from sales of these securities to fund our operations, as necessary. The cost of short-term investments is adjusted for amortization of premiums or accretion of discounts to maturity, and such amortization or accretion is included in interest income. Dividend and interest income is recognized as interest income on the statements of operations and comprehensive loss when earned. Short-term investments are classified as available-for-sale securities and carried at fair value with unrealized gains and losses recorded in other comprehensive loss and included as a separate component of stockholders' equity (deficit). Realized gains and losses from the sale of available-for-sale securities and declines in value judged to be other than temporary on short-term investments, if any, are determined on a specific identification basis and are reclassified out of comprehensive loss and included in interest income on the statements of operations and comprehensive loss.

Fair Value Measurements

Fair value is defined as the exit price, representing the amount that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants. As such, fair value is a market-based measurement that should be determined based on assumptions that market participants would use in pricing an asset or liability. As a basis for considering such assumptions, the guidance establishes a three-tier fair value hierarchy, which prioritizes the inputs used in measuring fair value as follows:

Level 1 - Quoted prices (unadjusted) in active markets for identical assets or liabilities;

Level 2 - Inputs other than quoted prices included within Level 1 that are either directly or indirectly observable;

Level 3 - Unobservable inputs in which little or no market activity exists, therefore requiring an entity to develop its own assumptions about the assumptions that market participants would use in pricing.

Concentration of Credit Risk

Financial instruments that potentially subject us to significant concentrations of credit risk consist primarily of cash, cash equivalents and short-term investments. We maintain deposits in federally insured financial institutions in excess of federally insured limits. We have established guidelines to limit our exposure to credit risk by placing investments with high credit quality financial institutions, diversifying our investment portfolio and placing investments with maturities that maintain safety and liquidity.

Property and Equipment

Property and equipment are stated at cost and depreciated using the straight-line method over the estimated useful lives of the assets which is three years for each asset class.

Impairment of Long-Lived Assets

We review our long-lived assets for impairment whenever events or changes in circumstances indicate that the carrying value of an asset may not be recoverable. If such circumstances are determined to exist, an estimate of undiscounted future cash flows produced by the long-lived asset, including its eventual residual value, is compared to the carrying value to determine whether impairment exists. In the event that such cash flows are not expected to be sufficient to recover the carrying amount of the assets, the assets are written-down to their estimated fair values. While our current and historical operating losses and negative cash flows are indicators of impairment, we believe that future cash flows to be received support the carrying value of our long-lived assets and, accordingly, have not recognized any impairment losses through December 31, 2015.

Research and Development Expenses

Research and development expenses consist of salaries, benefits, and other personnel costs, preclinical and clinical trial costs, manufacturing costs for non-commercial products, and research and development facilities costs. All such costs are charged to research and development expense as incurred when these expenditures have no alternative future uses. Payments that we make in connection with in-licensed technology for a particular research and development project that have no alternative future uses (in other research and development projects or otherwise) and therefore no separate economic values are expensed as research and development costs at the time such costs are incurred. As of December 31, 2015, we have no in-licensed technologies that have alternative future uses in research and development projects or otherwise.

Clinical Trial Costs and Accruals

A significant portion of our clinical trial costs relate to contracts with contract research organizations, or CROs. The financial terms of our CRO contracts may result in payment flows that do not match the periods over which materials or services are provided to us under such contracts. Our objective is to reflect the appropriate clinical trial expenses in our financial statements by matching those expenses with the period in which services and efforts are expended. As part of the process of preparing our financial statements, we rely on cost information provided by our CROs (concerning monthly expenses as well as reimbursement for pass through costs). We are also required to estimate certain of our expenses resulting from our obligations under our CRO contracts. Accordingly, our clinical trial accrual is dependent upon the timely and accurate reporting of CROs and other third-party vendors. If the contracted amounts are modified (for instance, as a result of changes in the clinical trial protocol or scope of work to be performed), we modify our accruals accordingly on a prospective basis. Revisions in the scope of a contract are charged to expense in the period in which the facts that give rise to the revision become reasonably certain. Historically, we have had no material changes in clinical trial expense that had a material impact on our results of operations or financial position.

Patent Costs

We expense all costs as incurred in connection with patent applications, including direct application fees, and the legal and consulting expenses related to making such applications, and such costs are included in general and administrative expenses on the statements of operations and comprehensive loss.

Share-Based Payments

Our share-based awards are measured at fair value on the date of grant based upon the estimated fair value of common stock. The fair value of awards expected to vest are recognized and amortized on a straight-line basis over the requisite service period of the award less estimated forfeitures. The fair value of each stock option is estimated on the date of grant using the Black-Scholes option pricing model that requires the use of subjective assumptions including volatility, expected term, risk-free rate, and the fair value of the underlying common stock.

Awards granted to non-employees are subject to periodic revaluation over their vesting terms. The fair value of non-employee awards is remeasured at each reporting period as the underlying awards vest unless the instruments are fully vested, immediately exercisable and nonforfeitable on the date of grant. We record the expense for stock option grants to non-employees based on the estimated fair value of the stock options using the Black-Scholes option pricing model. Estimated fair value of the restricted stock awards granted to non-employees is recorded on the earlier of the performance commitment date or the date the services required are completed and are remeasured at fair value during the service period. As non-employee restricted stock awards vest, they are remeasured at fair value and expensed based on the intrinsic value method which is measured as the difference between the exercise price paid for the restricted stock award and the fair value of the shares as the right of the repurchase lapses each vesting period.

Income Taxes

Income taxes have been accounted for using the asset and liability method. Under the asset and liability method, deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial carrying amounts of existing assets and liabilities and their respective tax bases and operating loss and tax credit carryforwards. Deferred tax assets and liabilities are measured using enacted tax rates applicable to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in income in the period that includes the enactment date. A valuation allowance against deferred tax assets is recorded if, based upon the weight of all available evidence, it is more likely than not that some or all of the deferred tax assets will not be realized. For uncertain tax positions that meet “a more likely than not” threshold, we recognize the benefit of uncertain tax positions in the financial statements.

Comprehensive Loss

Comprehensive loss is defined as the change in equity during the period from transactions and other events and non-owner sources. For the periods presented, accumulated other comprehensive loss consists solely of unrealized losses on marketable securities.

Net Loss per Share

We calculated basic net loss per common share by dividing the net loss by the weighted-average number of common shares outstanding for the period, without consideration for common stock equivalents. Diluted net loss per share is calculated by dividing the net loss by the weighted-average number of common share equivalents outstanding for the period determined using the treasury-stock method. Dilutive common stock equivalents are comprised of unvested restricted stock awards and outstanding stock options under our equity plan. For all periods presented, there is no difference in the number of shares used to calculate basic and diluted shares outstanding due to the antidilutive effect of the securities. Because of our net loss, unvested stock awards representing an aggregate of 3,232,350 and 4,532,874 shares of common stock and options to purchase an aggregate of 574,312 and zero shares of common stock are excluded from the calculation of diluted net loss per common share as of December 31, 2015 and 2014, respectively, due to the anti-dilutive effect of the securities.

Recent Accounting Pronouncements	12 Months Ended
Recent Accounting Pronouncements	Dec. 31, 2015
Accounting Changes And Error Corrections [Abstract]
Recent Accounting Pronouncements	3. Recent Accounting Pronouncements In November 2015, the Financial Accounting Standards Board, or FASB, issued Accounting Standard Update, or ASU, 2015-17, Balance Sheet Classification of Deferred Taxes, requiring all deferred tax assets and liabilities, and any related valuation allowance, to be classified as noncurrent on the balance sheet. This pronouncement is effective for fiscal years beginning after December 15, 2016, and interim periods within those annual periods. Early adoption is permitted. We have adopted this standard prospectively as of December 31, 2015, and no adjustments were made to prior periods. In February 2016, the FASB issued ASU 2016-02, Leases (Topic 842), which amends the existing accounting standards for accounting for leases. The amendments are to increase transparency and comparability among organizations by requiring recognition of lease assets and lease liabilities on the balance sheets and disclosure of key information about leasing arrangements. This pronouncement is effective for fiscal years beginning after December 15, 2018, and interim periods within those annual periods. Early adoption is permitted. The guidance is required to be adopted at the earliest period presented using a modified retrospective approach. We are currently evaluating the impact these amendments will have on our financial statements and whether we will adopt the guidance early.

- Definition

The entire disclosure of changes in accounting principles, including adoption of new accounting pronouncements, that describes the new methods, amount and effects on financial statement line items.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Change in Accounting Principle
-URI http://asc.fasb.org/extlink&oid=6507316

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Direct Effects of a Change in Accounting Principle
-URI http://asc.fasb.org/extlink&oid=6510796

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=56949863&loc=d3e22583-107794

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Indirect Effects of a Change in Accounting Principle
-URI http://asc.fasb.org/extlink&oid=6515603

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=56949863&loc=d3e22580-107794

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 270
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.10-01.(b)(6))
-URI http://asc.fasb.org/extlink&oid=27015980&loc=d3e46468-122699

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Accounting Change
-URI http://asc.fasb.org/extlink&oid=6503790

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=56949863&loc=d3e22499-107794

Reference 9: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Retrospective Application
-URI http://asc.fasb.org/extlink&oid=6523989

Reference 10: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 270
-SubTopic 10
-Section 45
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=51655806&loc=d3e765-108305

Reference 11: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 270
-SubTopic 10
-Section 45
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=51655806&loc=d3e725-108305

+ Details

Short-Term Investments

12 Months Ended

Dec. 31, 2015

Investments All Other Investments [Abstract]

Short-Term Investments

4. Short-Term Investments

The following table summarizes, by major security type, our short-term investments that are measured at fair value on a recurring basis as of December 31, 2015, in thousands:

		As of December 31, 2015
	Maturities	Amortized Cost		Unrealized Losses			Fair Value
Corporate debt securities	2 or less	$	22,758	$	(48	)	$	22,710
Commercial paper	1 or less		18,367		—			18,367
U.S. Treasury securities	2 or less		16,007		(18	)		15,989
Government sponsored entities	2 or less		13,258		(21	)		13,237
Total short-term investments		$	70,390	$	(87	)	$	70,303

The available-for-sale investments are classified as current assets, even though the stated maturity date may be one year or more beyond the current balance sheet date, which reflects management’s intention to use the proceeds from sales of these securities to fund our operations, as necessary. As of December 31, 2015, $57.6 million of our investments had maturities less than one year and $12.7 million had maturities between one to two years. There were $6.0 million of available-for-sale securities that matured during the year ended December 31, 2015. There were no unrealized gains or realized gains or losses for the year ended December 31, 2015. As of December 31, 2015, $51.9 million of our marketable securities were in gross unrealized loss positions, all of which had been in such position for less than twelve months. We reviewed our marketable securities as of December 31, 2015 and determined that the unrealized losses were not considered to be other-than-temporary based upon (i) the financial strength of the issuing institution and (ii) the fact that all securities have been in an unrealized loss position for less than twelve months. In addition, we do not intend to sell these securities and it is not more likely than not that we will be required to sell these securities before the recovery of their amortized cost basis. As such, we did not recognize any such impairment in our financial statements as of December 31, 2015. As of December 31, 2014, we did not have any cash equivalents or short-term investments.

- Definition

The entire disclosure for investments in certain debt and equity securities.

+ References + Details

Fair Value Measurements

12 Months Ended

Dec. 31, 2015

Fair Value Disclosures [Abstract]

Fair Value Measurements

5. Fair Value Measurements

Investment Securities

As of December 31, 2015, we had cash equivalents and short-term investments measured at fair value on a recurring basis. The carrying amounts of our financial instruments, which include cash equivalents, prepaid expenses, accounts payable, accrued expenses and all related party amounts approximate their fair values as of December 31, 2015, primarily due to their short-term nature. Fair value estimates of these instruments are made at a specific point in time, based on relevant market information. These estimates may be subjective in nature and involve uncertainties and matters of significant judgment and therefore cannot be determined with precision. As of December 31, 2014, we did not have any cash equivalents or short-term investments measured at fair value on a recurring basis.

Available-for-sale marketable securities consist of U.S. Treasury securities, which were measured at fair value using Level 1 inputs, and corporate debt securities, commercial paper and government sponsored entities, which were measured at fair value using Level 2 inputs. We determine the fair value of Level 2 related securities with the aid of valuations provided by third parties using proprietary valuation models and analytical tools. These valuation models and analytical tools use market pricing or prices for similar instruments that are both objective and publicly available, including matrix pricing or reported trades, benchmark yields, broker/dealer quotes, issuer spreads, two-sided markets, benchmark securities, bids and/or offers. We validate the fair values of Level 2 financial instruments by comparing these fair values to a third-party pricing source. No transfers between levels have occurred during the periods presented.

The following table summarizes, by major security type, our cash equivalents and short-term investments that are measured at fair value on a recurring basis and are categorized using the fair value hierarchy as of December 31, 2015, in thousands:

	As of December 31, 2015
	Balance		Level 1		Level 2		Level 3
Cash equivalents:
Money market funds	$	12,984	$	12,984	$	—	$	—

Short-term investments:
Corporate debt securities		22,710		—		22,710		—
Commercial paper		18,367		—		18,367		—
U.S. Treasury securities		15,989		15,989		—		—
Government sponsored entities		13,237		—		13,237		—
Total short-term investments		70,303		15,989		54,314		—
Total	$	83,287	$	28,973	$	54,314	$	—

Derivative Liability

Our license agreement with The Regents of the University of California San Francisco, or UCSF, which was amended in April 2015, provides for an indexed milestone payment upon the occurrence of a qualified financing and a subsequent initial public offering or a change of control event, or Indexed Milestone Event, as defined in the agreement. The indexed milestone was determined to qualify as an embedded derivative liability requiring an estimate of fair value. Prior to the completion of the Indexed Milestone Event, we estimated the fair value of our derivative liability at the time of issuance and subsequent remeasurement at each reporting date using a probability model that considered the probability of achieving the events that would trigger such liability and the estimated time period the liability would be outstanding.

Upon completion of the qualified financing event in March 2015 and the public offering completed in November 2015, the indexed milestone payment was determined to be $464,000. As of December 31, 2015, the balance of the derivative liability was $232,000. No transfers between levels have occurred during the periods presented. According to the payment terms as defined in the agreement, 50% of the liability was due and paid in December 2015, 30 days after the Indexed Milestone Event, and the remaining 50% will be due in November 2016. As such, the $232,000 derivative liability balance was reclassified to current liabilities and is included in accounts payable and accrued expenses on the balance sheets.

The following table provides a reconciliation of the derivative liability, in thousands:

	Derivative Liability
Balance at August 22, 2014 (Inception)	$	—
Issuance of derivative liability		196
Balance at December 31, 2014		196
Change in fair value⁽¹⁾		268
Payments		(232	)
Balance at December 31, 2015	$	232

(1)

The amount is included in research and development expenses on the statements of operations and comprehensive loss.

Property and Equipment, Net

12 Months Ended

Dec. 31, 2015

Property Plant And Equipment [Abstract]

Property and Equipment, Net

6. Property and Equipment, Net

Property and equipment consisted of the following, in thousands:

	December 31,
	2015			2014
Computer equipment	$	85		$	26
Software		7			2
Property and equipment, gross		92			28
Less: accumulated depreciation		(21	)		(1	)
Property and equipment, net	$	71		$	27

Depreciation expense was $20,000 and $1,000 for the year ended December 31, 2015 and period from August 22, 2014 (Inception) to December 31, 2014, respectively.

Accounts Payable and Accrued Liabilities

12 Months Ended

Dec. 31, 2015

Payables And Accruals [Abstract]

Accounts Payable and Accrued Liabilities

7. Accounts Payable and Accrued Liabilities

Accounts payable and accrued liabilities consisted of the following, in thousands:

	December 31,
	2015		2014
Accounts payable	$	902	$	226
Accrued compensation and benefits		1,282		39
Other accrued expenses		1,934		581
Total accounts payable and accrued expenses	$	4,118	$	846

Notes Payable	12 Months Ended
Notes Payable	Dec. 31, 2015
Debt Disclosure [Abstract]
Notes Payable	8. Notes Payable Araxes Convertible Note In October 2014, we entered into a Note Purchase Agreement and Convertible Promissory Note with an affiliated company Araxes Pharma LLC, or Araxes, under which Araxes provided a $2.0 million loan in the form of a convertible promissory note. In connection with the Private Placement, the total amount of unpaid principal and accrued interest as of February 28, 2015 was automatically converted into 326,443 shares of our common stock. Araxes Asset Purchase Agreement – Convertible Note As consideration for the patents acquired under the Araxes Asset Purchase Agreement entered into in December 2014, Araxes issued a convertible promissory note equal to the purchase price of the patent rights of $500,000. In connection with the Private Placement, the total amount of unpaid principal and accrued interest as of February 28, 2015 under the note was automatically converted into 80,293 shares of our common stock. January 2015 Convertible Notes In January 2015, we entered into a Note Purchase Agreement and Convertible Promissory Note for a $3.0 million loan with various persons and entities named within the agreement, or the January 2015 Note Holders, of which $710,000 were with certain officers and certain officers’ related parties. In connection with the Private Placement, the total amount of unpaid principal and accrued interest as of February 28, 2015 under the note was automatically converted into 479,667 shares of our common stock. JJDC Convertible Note In accordance with the license agreement with Janssen Pharmaceutica NV, a foreign entity headquartered in Belgium and an affiliate of Johnson & Johnson, Inc., or Janssen, in January 2015 we entered into a Convertible Promissory Note with Janssen’s affiliated company, Johnson & Johnson Innovation – JJDC, Inc., for $1.0 million. In connection with the Private Placement, the total amount of unpaid principal and accrued interest as of February 28, 2015 under the note was automatically converted into 159,615 shares of our common stock. February 2015 Convertible Notes In February 2015, we entered into a Note Purchase Agreement and Convertible Promissory Note with entities named within the agreement, or the February 2015 Note Holders, under which the February 2015 Note Holders provided a $1.0 million loan in the form of convertible promissory notes. In connection with the Private Placement, the total amount of unpaid principal and accrued interest as of February 28, 2015 under the note was automatically converted into 158,852 shares of our common stock.

License Agreements	12 Months Ended
License Agreements	Dec. 31, 2015
License Agreements [Abstract]
License Agreements	9. License Agreements Janssen License Agreement In December 2014, we entered into a license agreement with Janssen, under which we received certain intellectual property rights related to tipifarnib in the field of oncology for a non-refundable $1.0 million upfront license fee and payments upon achievement of certain development and sales-based milestones. Tipifarnib is a clinical stage compound and all ongoing development, regulatory and commercial work will be completed fully and at our sole expense. Under the license agreement, Janssen has a first right to negotiate for an exclusive license back from us to develop and commercialize tipifarnib on terms to be negotiated in good faith. Janssen may exercise this right of first negotiation during a 60-day period following delivery of clinical data as specified in the agreement. The agreement will terminate upon the last-to-expire patent rights or last-to-expire royalty term, or may be terminated by us with 180 days written notice of termination. Either party may terminate the agreement in the event of material breach of the agreement that is not cured within 45 days. Janssen may also terminate the agreement due to our lack of diligence that is not cured within a three-month period. The upfront license fee was recorded as research and development expense for the period from August 22, 2014 (Inception) to December 31, 2014 and paid in January 2015. Subsequent to such payment, in accordance with the agreement, we entered into a convertible promissory note with Janssen’s affiliated company, Johnson & Johnson Innovation—JJDC, Inc. as described further in Note 8. License Agreement with The University of Michigan In December 2014, we entered into a license agreement with The Regents of The University of Michigan, or Michigan, under which we received certain license rights for a non-refundable upfront license, annual maintenance fees and payments upon achievement of certain development and sales-based milestones. The licensed asset consists of a number of compounds, which are in the lead discovery/lead optimization phase. All future development, regulatory and commercial work on the asset will be completed fully and at our sole expense. Michigan retains the right to use the asset for non-commercial research, internal and/or educational purposes, with the right to grant the same limited rights to other non-profit research institutions. Furthermore, the agreement stipulates contingent consideration for the issuance of shares equivalent to a set dollar value upon the occurrence of a qualified financing or a change of control event, as defined in the amendment to the agreement, consistent with the terms issued to any future investors or the per share consideration to be received by other shareholders. As a result of the Private Placement, we issued 79,113 shares of our common stock at a fair value of $500,000, which was recognized as research and development expense during the year ended December 31, 2015. The agreement will terminate upon the last-to-expire patent rights, or may be terminated by us at any time with 90 days written notice of termination or terminated by Michigan upon a bankruptcy by us, payment failure by us that is not cured within 30 days or a material breach of the agreement by us that is not cured within 60 days. The University of California San Francisco License Agreement In November 2014, we entered into a license agreement with UCSF, which was amended in April 2015, under which we received certain license rights. The agreement provided for an upfront payment as well as contingent milestone payments. Additionally, the agreement provides for a one-time indexed milestone payment upon the occurrence of an Indexed Milestone Event. The indexed milestone was determined to qualify as an embedded derivative liability, as described further in Note 5. Collectively, our license agreements with Janssen, Michigan and UCSF provide for specified development, regulatory and sales-based milestone payments up to a total of $81.7 million payable upon occurrence of each stated event, of which $1.2 million relates to the initiation of certain development activities, $30.5 million relates to the achievement of specified regulatory approvals for the first indication and up to $50.0 million for the achievement of specified levels of product sales. Additional payments will be due for each subsequent indication if specified regulatory approvals are achieved. All milestone payments under the agreements will be recognized as research and development expense upon completion of the required events because the triggering events are not considered to be probable until they are achieved. As of December 31, 2015, we have not achieved any milestones under the agreements. Furthermore, if all the programs are successfully commercialized, we will be required to pay tiered royalties on annual net product sales ranging from the low single digits to the low teens, depending on the volume of sales and the respective agreement. Araxes Asset Purchase Agreement In December 2014, we entered into an asset purchase agreement with Araxes, which was amended and restated in February 2015, under which we purchased certain early stage patent rights related to compounds in the field of oncology for a purchase price of $500,000 payable under a convertible promissory note. All ongoing development, regulatory and commercial work will be completed fully and at our sole expense. The agreement allows for contingent milestone payments of $9.7 million throughout development and commercialization of the asset, of which $1.2 million relates to the initiation of certain development activities, and $8.5 million relates to the submission of certain regulatory filings and receipt of certain regulatory approvals. Additional payments will be due for each subsequent indication if specified regulatory approvals are achieved. We will recognize the milestones as expense when each event occurs. As of December 31, 2015, we have not achieved any milestones under the agreement. Furthermore, if the program is successfully commercialized, we will be required to pay tiered royalties on annual net product sales ranging in the low single digits, depending on the volume of sales. All milestone payments under the agreement will be recognized upon completion of the required events because the triggering events will not be considered to be probable until they are achieved.

Commitments and Contingencies

12 Months Ended

Dec. 31, 2015

Commitments And Contingencies Disclosure [Abstract]

Commitments and Contingencies

10. Commitments and Contingencies

Sponsored Research Agreement with The University of Michigan

In February 2015, we entered into a Sponsored Research Agreement with Michigan under which we agreed to sponsor up to $2.7 million of research at Michigan over a three-year period. We receive a non-exclusive right to any technology developed under this agreement and have an option right for an exclusive right to any such licenses developed under the agreement. The Sponsored Research Agreement allows for termination with notice at any time by us. In the event of termination by us prior to the second anniversary of the agreement, other than due to breach by Michigan, we will be required to pay costs budgeted through the second anniversary up to $2.0 million of the sponsored research amount. Any costs incurred for the Sponsored Research Agreement will be expensed as incurred. For the year ended December 31, 2015, we recorded approximately $878,000 in research and development expense under this research agreement.

Operating Leases

In August 2014, we entered into a sublease agreement, or the Sublease, with Araxes for office space for a monthly rent of $4,680 per month. The Sublease includes rent escalation of 3% per year. The Sublease was amended effective September 1, 2014 to provide for a monthly rent of $4,820 per month. In addition to the base monthly rent, we are obligated to pay for operating expenses, taxes, insurance, and utilities applicable to the subleased property. The Sublease will expire on August 30, 2016. We plan to extend the term of the Sublease.

In August 2015, we entered into a lease agreement for approximately 3,766 square feet of office space located in Cambridge, Massachusetts. We paid a security deposit of approximately $44,000. The lease is subject to a 60 month term expiring on August 1, 2020, with initial monthly rent of approximately $21,000 per month, and subject to a 1.4% annual rent increase. Total base rent payable over the lease period is $1.3 million. In addition to base monthly rent, we are obligated to pay for taxes, insurance and utilities applicable to the leased property.

Future minimum payments required under the facility leases as of December 31, 2015 are summarized as follows, in thousands:

Year Ending December 31,
2016	$	299
2017		263
2018		266
2019		270
2020		159
Total future minimum lease payments	$	1,257

Rent expense for the year ended December 31, 2015 and period from August 22, 2014 (Inception) to December 31, 2014 was $267,000 and $27,000, respectively.

Charitable Gift

We are obligated to make a charitable gift of $285,000 to the Leukemia and Lymphoma Society in connection with the Michigan agreement described in Note 9 to be paid in three equal parts: the first part was due and paid in January 2015, the second part was due and paid in January 2016 and the final part is due in January 2017. We recognized $285,000 as research and development expenses for the period from August 22, 2014 (Inception) to December 31, 2014. As of December 31, 2014, $190,000 was included in accounts payable and accrued expenses and $95,000 in long-term liabilities on the balance sheets. As of December 31, 2015, $95,000 was included in current liabilities and $95,000 in long-term liabilities on the balance sheets.

Litigation

From time to time, we may be involved in disputes, including litigation, relating to claims arising out of operations in the normal course of our business. Any of these claims could subject us to costly legal expenses and, while we generally believe that we have adequate insurance to cover many different types of liabilities, our insurance carriers may deny coverage or our policy limits may be inadequate to fully satisfy any damage awards or settlements. If this were to happen, the payment of any such awards could have a material adverse effect on our results of operations and financial position. Additionally, any such claims, whether or not successful, could damage our reputation and business. We currently are not a party to any legal proceedings, the adverse outcome of which, in management’s opinion, individually or in the aggregate, would have a material adverse effect on our results of operations or financial position.

Stockholders' Equity	12 Months Ended
Stockholders' Equity	Dec. 31, 2015
Equity [Abstract]
Stockholders' Equity	11. Stockholders’ Equity Immediately prior to the Merger, on March 6, 2015, Prior Kura sold an aggregate of 9,485,566 shares of its common stock at a price of $6.32 per share, for net proceeds of approximately $55.8 million, net of $4.1 million in fees. The Private Placement represented a qualified financing conversion event pursuant to Prior Kura’s then outstanding convertible promissory notes. As such, upon the closing of the Private Placement, an aggregate of $7.5 million in principal under such convertible promissory notes and $115,000 in accrued interest through February 28, 2015 automatically converted into 1,204,870 shares of our common stock (which shares and net proceeds are included in the amounts set forth above). In addition, we incurred approximately $568,000 in costs related to the Merger which were accounted for as financing costs in additional paid-in capital. In November 2015, we completed a public offering in which we sold an aggregate of 6,883,467 shares of common stock at a price of $8.00 per share. Net proceeds from the public offering, after deducting underwriting discounts, commissions and offering expenses, were approximately $50.3 million. Effective April 13, 2015, pursuant to our amended and restated certificate of incorporation, we have authorized capital stock consisting of 200,000,000 shares of common stock, par value $0.0001 per share, and 10,000,000 shares of preferred stock, par value $0.0001 per share.

- Definition

The entire disclosure for shareholders' equity comprised of portions attributable to the parent entity and noncontrolling interest, including other comprehensive income. Includes, but is not limited to, balances of common stock, preferred stock, additional paid-in capital, other capital and retained earnings, accumulated balance for each classification of other comprehensive income and amount of comprehensive income.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(d),(e))
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 4
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SAB TOPIC 4.E)
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Reference 4: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21488-112644

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.29-31)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
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-Paragraph 4
-Subparagraph (SAB TOPIC 4.C)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187143-122770

Reference 7: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21506-112644

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
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-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

Reference 9: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 30
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6405834&loc=d3e23285-112656

Reference 10: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21475-112644

Reference 11: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Preferred Stock
-URI http://asc.fasb.org/extlink&oid=6521494

Reference 12: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
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-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

Reference 13: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21564-112644

Reference 14: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 4
-Section E

Reference 15: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 4
-Section C

+ Details

Equity Incentive Plan

12 Months Ended

Dec. 31, 2015

Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]

Equity Incentive Plan

12. Equity Incentive Plan

In August 2014, Prior Kura adopted the Prior Kura 2014 Equity Incentive Plan. In connection with the Merger as discussed in Note 1, at the Effective Time of the Merger, we adopted the Prior Kura 2014 Equity Incentive Plan and approved the amendment and restatement of the Prior Kura 2014 Equity Incentive Plan pursuant to the 2014 Plan, which became effective April 13, 2015. Under the 2014 Plan, a total of 5,975,000 shares were initially reserved for issuance.

As of December 31, 2015, there were 478,272 shares of common stock reserved for future stock awards under the 2014 Plan. The number of shares available for future grant under our 2014 Plan will automatically increase on January 1 of each year by 4% of the total number of shares of our common stock outstanding on December 31 of the preceding calendar year, subject to the ability of our board of directors to take action to reduce the size of the increase in any given year. On January 1, 2016, the initial automatic increase pursuant to the 2014 Plan occurred, resulting in 854,822 additional shares available for future grant under the 2014 Plan. The 2014 Plan provides for the grant of incentive stock options, non-statutory stock options, restricted stock awards, restricted stock unit awards, performance-based stock awards and other forms of equity compensation to our employees and other service providers.

In addition, as of December 31, 2015, we had 25,000 shares of common stock reserved for future issuance under our 2015 Employee Stock Purchase Plan, or ESPP, which has not been implemented as of December 31, 2015. The number of shares of our common stock reserved for issuance under the ESPP will automatically increase on January 1 of each calendar year by the lesser of 1% of the total number of shares of our common stock outstanding on December 31 of the preceding calendar year and 2,000,000 shares, subject to the ability of our board of directors to take action to reduce the size of the increase in any given year. On January 1, 2016, the initial automatic increase pursuant to the ESPP occurred, resulting in 213,705 additional shares available for future grant under the ESPP.

Stock Options

The exercise price of all stock options granted was equal to no less than the estimated fair market value of such stock on the date of grant. Stock options generally vest over a three to four-year period. The maximum contractual term for all options is ten years. The following is a summary of stock option activity for the year ended December 31, 2015, in thousands (except per share and years data):

	Number of Shares			Weighted-Average Exercise Price per Share		Weighted-Average Remaining Contractual Term (years)		Aggregate Intrinsic Value
Outstanding at December 31, 2014		—
Granted		630		$	8.85
Canceled/forfeited		(56	)	$	6.32
Outstanding at December 31, 2015		574		$	9.10		9.1	$	761
Exercisable at December 31, 2015		24		$	6.62		2.3	$	48

The assumptions used to estimate the fair value of stock options granted to employees in the year ended December 31, 2015 using the Black-Scholes option pricing model were as follows:

Weighted-average grant date fair value per share	$	4.16
Expected volatility	70.8% — 72.8%
Expected term (in years)	6.00 — 6.08
Risk free interest rate	1.7% — 1.8%
Expected dividend yield		—

There were no stock options granted for the period from August 22, 2014 (Inception) to December 31, 2014. In estimating fair value for stock options issued under the 2014 Plan, expected volatility was based on historical volatility of comparable publicly-traded companies because our common stock has only been publicly traded since September 16, 2015. Due to the lack of historical option exercise data, we estimated the expected term using the simplified method. The risk-free interest rates are based on the U.S. Treasury zero-coupon bonds with maturities similar to those of the expected term of the award being valued. The expected dividend yield of zero reflects that we have not paid cash dividends since inception and do not intend to pay cash dividends in the foreseeable future. We apply an estimate of forfeitures at the time of grant based on historical experience and revise our estimate in subsequent periods if actual forfeitures differ from those estimates.

For the year ended December 31, 2015 and period from August 22, 2014 (Inception) to December 31, 2014, we recognized $399,000 and zero expense related to options, respectively. As of December 31, 2015, unrecognized estimated compensation expense related to options was $1.9 million, which is expected to be recognized over the weighted-average remaining requisite service period of approximately 3.2 years.

Restricted Stock Awards

Restricted stock awards were granted at a price equal to the estimated fair market value on the date of grant. The restricted stock awards generally vest over four years from the original vesting date, with certain grants subject to one-year cliff vesting. The vesting provisions of individual awards may vary as approved by our Board of Directors. In connection with the issuance of restricted common stock, we maintain a repurchase right where shares of restricted common stock are released from such repurchase right over a period of time of continued service by the recipient. The repurchase price for unvested stock awards will be the lower of (i) the fair market value of the shares of common stock on the date of repurchase or (ii) their original purchase price. As of December 31, 2015, there were 3,232,350 shares subject to repurchase, of which 2,716,515 shares were related to employee stock awards, and 515,835 shares were related to non-employee stock awards, respectively.

The following is a summary of restricted stock awards activity for the year ended December 31, 2015 and period from August 22, 2014 (Inception) to December 31, 2014, in thousands (except per share data):

	Number of Shares			Employee			Non-employee			Weighted-Average Grant Date Fair Value
Unvested at August 22, 2014 (Inception)		—			—			—		$	—
Granted		4,944			4,096			848		$	0.002
Vested		(411	)		(322	)		(89	)	$	0.002
Unvested at December 31, 2014		4,533			3,774			759		$	0.002
Granted		—			—			—		$	—
Vested		(1,279	)		(1,036	)		(243	)	$	0.002
Forfeited		(21	)		(21	)		—		$	0.011
Unvested at December 31, 2015		3,233			2,717			516		$	0.002
Vested at December 31, 2015		1,690			1,358			332		$	0.002

For the year ended December 31, 2015 and period from August 22, 2014 (Inception) to December 31, 2014, we recognized expense related to restricted stock awards totaling $1.9 million and $237,000, respectively, of which $1.7 million and $237,000 in expense related to non-employee restricted stock awards, respectively. As of December 31, 2015, unrecognized estimated compensation expense related to employee restricted stock awards was $360,000, which is expected to be recognized over the weighted-average remaining requisite service period of approximately 2.7 years.

The following table summarizes share-based compensation expense for all share-based compensation arrangements, in thousands:

			Period From
			August 22, 2014
	Year Ended		(Inception) to
	December 31, 2015		December 31, 2014
Research and development	$	1,916	$	233
General and administrative		343		4
Total share-based compensation expense	$	2,259	$	237

Related Party Transactions

12 Months Ended

Dec. 31, 2015

Related Party Transactions

13. Related Party Transactions

As discussed in Note 8, in January 2015, we entered into a Note Purchase Agreement and Convertible Promissory Note for a $3.0 million loan with the January 2015 Note Holders, of which $710,000 were with certain officers and certain officers’ related parties. In connection with the Private Placement, the total amount of unpaid principal and accrued interest as of February 28, 2015 under the notes was automatically converted into 479,667 shares of our common stock.

Our president and chief executive officer is also the sole managing member of our affiliated company Araxes. Four individuals are significant stockholders of each of us and Araxes. The following is a summary of all transactions with Araxes for the year ended December 31, 2015 and period from August 22, 2014 (Inception) to December 31, 2014:

Asset Purchase Agreement

Under the asset purchase agreement with Araxes described in Note 9, we purchased certain assets for an upfront purchase price of $500,000 payable under a convertible promissory note. This amount was recorded as research and development expenses, related party for the period from August 22, 2014 (Inception) to December 31, 2014. Additionally, the note was included within noncurrent notes payable, related party on the balance sheets as of December 31, 2014.

As described in Note 8, in connection with the Private Placement, the total amount of unpaid principal and accrued interest as of February 28, 2015 under the convertible note issued in connection with the Araxes asset purchase was automatically converted into 80,293 shares of our common stock.

Convertible Promissory Note

As described in Note 8, in connection with the Private Placement, the total amount of unpaid principal and accrued interest as of February 28, 2015 under the convertible note issued in connection with the Araxes $2.0 million loan was automatically converted into 326,443 shares of our common stock.

Facility Sublease

We sublease office space from Araxes for a base rent of approximately $5,000 per month plus operating expenses, taxes, insurance, and utilities applicable to the subleased property. Rent expense related to the Sublease for the years ended December 31, 2015 and period from August 22, 2014 (Inception) to December 31, 2014 was $58,000 and $15,000, respectively. The Sublease will expire on August 30, 2016. We plan to extend the term of the Sublease.

Management Fees

We have a management services agreement with Araxes under which Araxes pays us a fixed monthly fee of $100,000 for management services. In addition, the agreement allows for Araxes to reimburse us an amount equal to the number of full time equivalents, or FTE, performing research and development services for Araxes, at an annual FTE rate of $350,000, plus actual expenses as reasonably incurred. The initial term of this agreement expired on December 31, 2015 but, pursuant to the terms of the agreement, renews automatically for additional consecutive one-year periods. The agreement may be terminated by either party with a notice of at least 30 days prior to the expiration of the renewal term. For the year ended December 31, 2015 and period from August 22, 2014 (Inception) to December 31, 2014, we recorded reimbursements of $330,000 and $30,000, respectively, for research and development services provided to Araxes, which was recorded on the statements of operations and comprehensive loss as a reduction to research and development expenses. As of December 31, 2015 and 2014, $430,000 and $30,000 related to management fees and reimbursements of research and development services, respectively, are included in accounts receivable, related party on the balance sheets.

Services Agreement

We have a services agreement with Wellspring Biosciences LLC, a wholly owned subsidiary of Araxes, which allows for payment of research and development services provided to us of an amount equal to the number of FTE’s performing the services, at an annual FTE rate of $400,000, plus actual expenses as reasonably incurred. The initial term of this services agreement expired on December 31, 2015 but, pursuant to the terms of the agreement, renews automatically for additional consecutive one-year periods. The agreement may be terminated by either party with a notice of at least 30 days prior to the expiration of the then-renewal term. For the year ended December 31, 2015 and the period from August 22, 2014 (Inception) to December 31, 2014, we recognized $4.1 million and $130,000, respectively, from research and development services provided to us under this agreement as research and development expense, related party on the statements of operations and comprehensive loss. As of December 31, 2015 and 2014, $911,000 and zero, respectively, related to research and development services under this agreement are included in accrued expenses, related party on the balance sheets.

- Definition

The entire disclosure for related party transactions. Examples of related party transactions include transactions between (a) a parent company and its subsidiary; (b) subsidiaries of a common parent; (c) and entity and its principal owners; and (d) affiliates.

+ References + Details

Employee Benefit Plan	12 Months Ended
Employee Benefit Plan	Dec. 31, 2015
Postemployment Benefits [Abstract]
Employee Benefit Plan	14. Employee Benefit Plan We have a defined contribution 401(k) plan for all employees. Employees are eligible to participate in the plan if they are at least 21 years of age or older. Under the terms of the plan, employees may make voluntary contributions as a percentage or defined amount of compensation. We do not provide a matching contribution program.

Income Taxes

12 Months Ended

Dec. 31, 2015

Income Tax Disclosure [Abstract]

Income Taxes

15. Income Taxes

We file tax returns as prescribed by the tax laws of the jurisdictions in which we operate. In the normal course of business, our 2015 and 2014 tax years will be subject to examination by the federal and state jurisdictions where applicable. We have not been, nor are we currently, under examination by the federal or any state tax authority.

Our effective income tax rate differs from the statutory federal rate of 34% at December 31, 2015 and 2014, due to the following, in thousands:

				Period From
				August 22, 2014
	Year Ended			(Inception) to
	December 31, 2015			December 31, 2014
Income taxes at statutory federal rate	$	(7,693	)	$	(1,248	)
State income tax, net of federal benefit		(1,412	)		(225	)
Share-based compensation		712			80
Research and development tax credits		(544	)		(28	)
Other		29			13
Valuation allowance		8,908			1,408
Income tax expense	$	—		$	—

Significant components of our deferred tax assets at December 31, 2015 and 2014 are shown below, in thousands:

	December 31,
	2015			2014
Deferred tax assets
Net operating loss carryforwards	$	7,975		$	442
Intangibles		999			732
Research and development tax credit carryforwards		573			28
Accruals		662			205
Other		106			1
Total deferred tax assets		10,315			1,408
Less valuation allowance		(10,315	)		(1,408	)
Net deferred tax assets	$	—		$	—

At December 31, 2015, we had federal and state net operating loss carryforwards of $19.5 million and $23.5 million, respectively. The federal loss carryforwards begin to expire in 2034, unless previously utilized. We have $23.4 million of state losses that begin to expire in 2034 and $66,000 of state loss carryforwards that begin to expire in 2030, unless previously utilized. We also have federal and state research credit carryforwards of $514,000 and $301,000, respectively. The federal research credits will begin to expire in 2034, unless previously utilized. The state research credits will carryforward indefinitely.

Management assesses the available positive and negative evidence to estimate if sufficient future taxable income will be generated to use existing deferred tax assets. Based on the weight of the evidence, including our limited existence and losses since inception, management has determined that it is more likely than not that the deferred tax assets will not be realized. The valuation allowance increased by $8.9 million from December 31, 2014 to December 31, 2015.

Pursuant to Sections 382 and 383 of the Internal Revenue Code of 1986, as amended, annual use of our net operating loss, or NOL, and research and development, or R&D, credit carryforwards may be limited in the event a cumulative change in ownership of more than 50% occurs within a three-year period. We have not completed a study to assess whether an ownership change has occurred or whether there have been ownership changes. If we have experienced an ownership change at any time since our formation, utilization of our NOL or R&D credit carryforwards would be subject to an annual limitation which may result in the expiration of a portion of the NOL or R&D credit carryforwards before utilization. Any carryforwards that will expire prior to utilization as a result of such limitations will be removed from deferred tax assets, with a corresponding reduction of the valuation allowance.

In accordance with authoritative guidance, the impact of an uncertain income tax position is recognized at the largest amount that is “more likely than not” to be sustained upon audit by the relevant taxing authority. An uncertain tax position will not be recognized if it has less than a 50% likelihood of being sustained.

The following table summarizes the activity related to our unrecognized tax benefits, in thousands:

	December 31,
	2015		2014
Gross unrecognized tax benefits at the beginning of the year	$	—	$	—
Increases from tax positions taken in the current year		167		—
Increases from tax positions taken in prior years		—		—
Decreases in tax positions taken in prior years		—		—
Tax settlements		—		—
Expiration of unrecognized tax benefits		—		—
Gross unrecognized tax benefits at the end of the year	$	167	$	—

Our practice is to recognize interest and penalties related to income tax matters in income tax expense. We did not have any accrued interest or penalties included on our balance sheets and have not recognized interest and penalties on the statements of operations and comprehensive loss for the year ended December 31, 2015 or the period from August 22, 2014 (Inception) to December 31, 2014.

We do not expect that there will be a significant change in the unrecognized tax benefits over the next 12 months. Due to the existence of the valuation allowance, future changes in our unrecognized tax benefits will not impact our effective tax rate.

Summary of Significant Accounting Policies (Policies)

12 Months Ended

Dec. 31, 2015

Accounting Policies [Abstract]

Use of Estimates

Segment Reporting

Cash and Cash Equivalents

Short-Term Investments

Fair Value Measurements

Level 1 - Quoted prices (unadjusted) in active markets for identical assets or liabilities;

Level 2 - Inputs other than quoted prices included within Level 1 that are either directly or indirectly observable;

Concentration of Credit Risk

Property and Equipment

Property and equipment are stated at cost and depreciated using the straight-line method over the estimated useful lives of the assets which is three years for each asset class.

Impairment of Long-Lived Assets

Research and Development Expenses

Clinical Trial Costs and Accruals

Recent Accounting Pronouncements

In November 2015, the Financial Accounting Standards Board, or FASB, issued Accounting Standard Update, or ASU, 2015-17, Balance Sheet Classification of Deferred Taxes, requiring all deferred tax assets and liabilities, and any related valuation allowance, to be classified as noncurrent on the balance sheet. This pronouncement is effective for fiscal years beginning after December 15, 2016, and interim periods within those annual periods. Early adoption is permitted. We have adopted this standard prospectively as of December 31, 2015, and no adjustments were made to prior periods.

In February 2016, the FASB issued ASU 2016-02, Leases (Topic 842), which amends the existing accounting standards for accounting for leases. The amendments are to increase transparency and comparability among organizations by requiring recognition of lease assets and lease liabilities on the balance sheets and disclosure of key information about leasing arrangements. This pronouncement is effective for fiscal years beginning after December 15, 2018, and interim periods within those annual periods. Early adoption is permitted. The guidance is required to be adopted at the earliest period presented using a modified retrospective approach. We are currently evaluating the impact these amendments will have on our financial statements and whether we will adopt the guidance early.

Short-Term Investments (Tables)

12 Months Ended

Dec. 31, 2015

Investments All Other Investments [Abstract]

Short-Term Investments Measured at Fair Value on Recurring Basis

The following table summarizes, by major security type, our short-term investments that are measured at fair value on a recurring basis as of December 31, 2015, in thousands:

		As of December 31, 2015
	Maturities	Amortized Cost		Unrealized Losses			Fair Value
Corporate debt securities	2 or less	$	22,758	$	(48	)	$	22,710
Commercial paper	1 or less		18,367		—			18,367
U.S. Treasury securities	2 or less		16,007		(18	)		15,989
Government sponsored entities	2 or less		13,258		(21	)		13,237
Total short-term investments		$	70,390	$	(87	)	$	70,303

Fair Value Measurements (Tables)

12 Months Ended

Dec. 31, 2015

Fair Value Disclosures [Abstract]

Schedule Of Fair Value Measurements, By Major Security Type

	As of December 31, 2015
	Balance		Level 1		Level 2		Level 3
Cash equivalents:
Money market funds	$	12,984	$	12,984	$	—	$	—

Short-term investments:
Corporate debt securities		22,710		—		22,710		—
Commercial paper		18,367		—		18,367		—
U.S. Treasury securities		15,989		15,989		—		—
Government sponsored entities		13,237		—		13,237		—
Total short-term investments		70,303		15,989		54,314		—
Total	$	83,287	$	28,973	$	54,314	$	—

Significant Impact of Changes in Assumptions on Fair Value of Derivative Liability

The following table provides a reconciliation of the derivative liability, in thousands:

	Derivative Liability
Balance at August 22, 2014 (Inception)	$	—
Issuance of derivative liability		196
Balance at December 31, 2014		196
Change in fair value⁽¹⁾		268
Payments		(232	)
Balance at December 31, 2015	$	232

(1)

The amount is included in research and development expenses on the statements of operations and comprehensive loss.

Property and Equipment, Net (Tables)

12 Months Ended

Dec. 31, 2015

Property Plant And Equipment [Abstract]

Property and Equipment, Net

Property and equipment consisted of the following, in thousands:

	December 31,
	2015			2014
Computer equipment	$	85		$	26
Software		7			2
Property and equipment, gross		92			28
Less: accumulated depreciation		(21	)		(1	)
Property and equipment, net	$	71		$	27

Accounts Payable and Accrued Liabilities (Tables)

12 Months Ended

Dec. 31, 2015

Payables And Accruals [Abstract]

Accounts Payable and Accrued Liabilities

Accounts payable and accrued liabilities consisted of the following, in thousands:

	December 31,
	2015		2014
Accounts payable	$	902	$	226
Accrued compensation and benefits		1,282		39
Other accrued expenses		1,934		581
Total accounts payable and accrued expenses	$	4,118	$	846

Commitments and Contingencies (Tables)

12 Months Ended

Dec. 31, 2015

Commitments And Contingencies Disclosure [Abstract]

Future Minimum Payments Required under Facility Leases

Future minimum payments required under the facility leases as of December 31, 2015 are summarized as follows, in thousands:

Year Ending December 31,
2016	$	299
2017		263
2018		266
2019		270
2020		159
Total future minimum lease payments	$	1,257

Equity Incentive Plan (Tables)

12 Months Ended

Dec. 31, 2015

Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]

Summary of Stock Option Activity

	Number of Shares			Weighted-Average Exercise Price per Share		Weighted-Average Remaining Contractual Term (years)		Aggregate Intrinsic Value
Outstanding at December 31, 2014		—
Granted		630		$	8.85
Canceled/forfeited		(56	)	$	6.32
Outstanding at December 31, 2015		574		$	9.10		9.1	$	761
Exercisable at December 31, 2015		24		$	6.62		2.3	$	48

Summary of Assumptions used to Estimate the Fair Value of Stock Options Under Black-Scholes Option Pricing Model

The assumptions used to estimate the fair value of stock options granted to employees in the year ended December 31, 2015 using the Black-Scholes option pricing model were as follows:

Weighted-average grant date fair value per share	$	4.16
Expected volatility	70.8% — 72.8%
Expected term (in years)	6.00 — 6.08
Risk free interest rate	1.7% — 1.8%
Expected dividend yield		—

Summary of Restricted Stock Awards Activity

	Number of Shares			Employee			Non-employee			Weighted-Average Grant Date Fair Value
Unvested at August 22, 2014 (Inception)		—			—			—		$	—
Granted		4,944			4,096			848		$	0.002
Vested		(411	)		(322	)		(89	)	$	0.002
Unvested at December 31, 2014		4,533			3,774			759		$	0.002
Granted		—			—			—		$	—
Vested		(1,279	)		(1,036	)		(243	)	$	0.002
Forfeited		(21	)		(21	)		—		$	0.011
Unvested at December 31, 2015		3,233			2,717			516		$	0.002
Vested at December 31, 2015		1,690			1,358			332		$	0.002

Summary of Share-based Compensation Expense

The following table summarizes share-based compensation expense for all share-based compensation arrangements, in thousands:

			Period From
			August 22, 2014
	Year Ended		(Inception) to
	December 31, 2015		December 31, 2014
Research and development	$	1,916	$	233
General and administrative		343		4
Total share-based compensation expense	$	2,259	$	237

Income Taxes (Tables)

12 Months Ended

Dec. 31, 2015

Income Tax Disclosure [Abstract]

Schedule of Effective Income Tax Rate Reconciliation

Our effective income tax rate differs from the statutory federal rate of 34% at December 31, 2015 and 2014, due to the following, in thousands:

				Period From
				August 22, 2014
	Year Ended			(Inception) to
	December 31, 2015			December 31, 2014
Income taxes at statutory federal rate	$	(7,693	)	$	(1,248	)
State income tax, net of federal benefit		(1,412	)		(225	)
Share-based compensation		712			80
Research and development tax credits		(544	)		(28	)
Other		29			13
Valuation allowance		8,908			1,408
Income tax expense	$	—		$	—

Components of Deferred Tax Assets

Significant components of our deferred tax assets at December 31, 2015 and 2014 are shown below, in thousands:

	December 31,
	2015			2014
Deferred tax assets
Net operating loss carryforwards	$	7,975		$	442
Intangibles		999			732
Research and development tax credit carryforwards		573			28
Accruals		662			205
Other		106			1
Total deferred tax assets		10,315			1,408
Less valuation allowance		(10,315	)		(1,408	)
Net deferred tax assets	$	—		$	—

Schedule of Activity Related to Unrecognized Tax Benefits

The following table summarizes the activity related to our unrecognized tax benefits, in thousands:

	December 31,
	2015		2014
Gross unrecognized tax benefits at the beginning of the year	$	—	$	—
Increases from tax positions taken in the current year		167		—
Increases from tax positions taken in prior years		—		—
Decreases in tax positions taken in prior years		—		—
Tax settlements		—		—
Expiration of unrecognized tax benefits		—		—
Gross unrecognized tax benefits at the end of the year	$	167	$	—

Organization and Basis of Presentation - Additional Information (Detail)			1 Months Ended	2 Months Ended	12 Months Ended
	Nov. 05, 2015 $ / shares shares	Mar. 06, 2015 USD ($) $ / shares shares	Nov. 30, 2015 USD ($)	Dec. 31, 2015 USD ($) $ / shares shares	Dec. 31, 2015 USD ($) $ / shares shares	Apr. 13, 2015 $ / shares	Dec. 31, 2014 $ / shares shares
Product Information [Line Items]
Common stock, shares issued \| shares		14,508,177		21,371,000	21,371,000		4,944,000
Redemption of pre merger common stock shares \| shares		5,000,000
Aggregate consideration of redemption		$ 70,000
Professional costs		$ 30,000
Reverse merger common share exchange ratio		0.5
Common stock, par value \| $ / shares		$ 0.0001		$ 0.0001	$ 0.0001	$ 0.0001	$ 0.0001
Common stock, shares issued \| shares	6,883,467
Common stock, issued price per share \| $ / shares	$ 8.00
Proceeds from issuance of common stock, net			$ 50,300,000	$ 50,300,000	$ 97,870,000
Private Placement
Product Information [Line Items]
Common stock, shares issued \| shares		9,485,566
Common stock, issued price per share \| $ / shares		$ 6.32
Proceeds from issuance of common stock, net		$ 55,800,000
Convertible promissory notes accrued interest		115,000
Conversion of common stock		$ 7,500,000
Prior Kura
Product Information [Line Items]
Percentage by Parent		100.00%

Summary of Significant Accounting Policies - Additional Information (Detail)	4 Months Ended	12 Months Ended
	Dec. 31, 2014 shares	Dec. 31, 2015 USD ($) Segment shares
Summary Of Significant Accounting Policies [Line Items]
Number of operating segments \| Segment		1
Property and equipment, estimated useful life		3 years
Impairment losses on long-lived assets \| $		$ 0
Unvested Stock Awards
Summary Of Significant Accounting Policies [Line Items]
Potentially dilutive securities	4,532,874	3,232,350
Employee Stock Option
Summary Of Significant Accounting Policies [Line Items]
Potentially dilutive securities	0	574,312

Short-Term Investments - Short-Term Investments Measured at Fair Value on Recurring Basis (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2015 USD ($)
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	$ 70,390
Unrealized Losses	(87)
Fair Value	$ 70,303
Corporate Debt Securities
Schedule Of Available For Sale Securities [Line Items]
Maturities	2 or less
Amortized Cost	$ 22,758
Unrealized Losses	(48)
Fair Value	$ 22,710
Commercial Paper
Schedule Of Available For Sale Securities [Line Items]
Maturities	1 or less
Amortized Cost	$ 18,367
Fair Value	$ 18,367
U.S. Treasury Securities
Schedule Of Available For Sale Securities [Line Items]
Maturities	2 or less
Amortized Cost	$ 16,007
Unrealized Losses	(18)
Fair Value	$ 15,989
Government Sponsored Entities
Schedule Of Available For Sale Securities [Line Items]
Maturities	2 or less
Amortized Cost	$ 13,258
Unrealized Losses	(21)
Fair Value	$ 13,237

Short-Term Investments - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Investments All Other Investments [Abstract]
Investments with maturities less than one year	$ 57,600,000
Investments with maturities between one to two years	12,700,000
Available-for-sale securities matured during the year	6,000,000
Available-for-sale securities, Unrealized gains	0
Available-for-sale securities, realized gains or losses	0
Cash equivalents or short-term investments		$ 0
Marketable securities gross unrealized loss positions for less than twelve months	$ 51,900,000

Fair Value Measurements - Fair Values of Investment Securities (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Short-term investments	$ 70,303
Cash equivalents and short-term investments		$ 0
Government Sponsored Entities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Short-term investments	13,237
Fair Value Measurements on Recurring Basis
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Short-term investments	70,303
Cash equivalents and short-term investments	83,287
Fair Value Measurements on Recurring Basis \| Level 1
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Short-term investments	15,989
Cash equivalents and short-term investments	28,973
Fair Value Measurements on Recurring Basis \| Level 2
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Short-term investments	54,314
Cash equivalents and short-term investments	54,314
Fair Value Measurements on Recurring Basis \| Money Market Funds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash equivalents	12,984
Fair Value Measurements on Recurring Basis \| Money Market Funds \| Level 1
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash equivalents	12,984
Fair Value Measurements on Recurring Basis \| Corporate Debt Securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Short-term investments	22,710
Fair Value Measurements on Recurring Basis \| Corporate Debt Securities \| Level 2
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Short-term investments	22,710
Fair Value Measurements on Recurring Basis \| Commercial Paper
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Short-term investments	18,367
Fair Value Measurements on Recurring Basis \| Commercial Paper \| Level 2
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Short-term investments	18,367
Fair Value Measurements on Recurring Basis \| U.S. Treasury Securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Short-term investments	15,989
Fair Value Measurements on Recurring Basis \| U.S. Treasury Securities \| Level 1
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Short-term investments	15,989
Fair Value Measurements on Recurring Basis \| Government Sponsored Entities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Short-term investments	13,237
Fair Value Measurements on Recurring Basis \| Government Sponsored Entities \| Level 2
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Short-term investments	$ 13,237

Fair Value Measurements - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2015	Nov. 30, 2015	Dec. 31, 2014
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Derivative liabilities indexed milestone payment amount		$ 464,000
Derivative liability	$ 232,000		$ 196,000
First portion due period after the Indexed Milestone Event	30 days
Derivative liability, current	$ 232,000
Embedded Derivative Liability Due in December 2015
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Milestone payments, percentage	50.00%
Embedded Derivative Liability Due in November 2016
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Milestone payments, percentage	50.00%

- Definition

Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, expected to be settled within one year or normal operating cycle, if longer. Includes assets not subject to a master netting arrangement and not elected to be offset.

+ References + Details

Fair Value Measurement - Summary of Significant Impact of Changes in Assumptions on Fair Value of Derivative Liability (Detail) - USD ($)

4 Months Ended

12 Months Ended

Dec. 31, 2014

Dec. 31, 2015

Fair Value Disclosures [Abstract]

Beginning balance

$ 196,000

Issuance of derivative liability

$ 196,000

Change in value of derivative liability

^[1]

268,000

Payments

(232,000)

Ending balance

$ 196,000

$ 232,000

[1]	The amount is included in research and development expenses on the statements of operations and comprehensive loss.

Property and Equipment, Net (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 92	$ 28
Less: accumulated depreciation	(21)	(1)
Property and equipment, net	71	27
Computer Equipment
Property Plant And Equipment [Line Items]
Property and equipment, gross	85	26
Software
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 7	$ 2

Property and Equipment, Net - Additional Information (Detail) - USD ($) $ in Thousands	4 Months Ended	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2015
Property Plant And Equipment [Abstract]
Depreciation expense	$ 1	$ 20

Accounts Payable and Accrued Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Payables And Accruals [Abstract]
Accounts payable	$ 902	$ 226
Accrued compensation and benefits	1,282	39
Other accrued expenses	1,934	581
Total accounts payable and accrued expenses	$ 4,118	$ 846

Notes Payable - Additional Information (Detail) - USD ($)	Mar. 06, 2015	Feb. 11, 2015	Jan. 20, 2015	Jan. 12, 2015	Dec. 23, 2014	Oct. 08, 2014
JJDC, Inc
Debt Instrument [Line Items]
Convertible promissory note			$ 1,000,000
Unpaid principal and accrued interest converted into common stock shares	159,615
January 2015 Convertible Notes
Debt Instrument [Line Items]
Convertible promissory note				$ 3,000,000
Unpaid principal and accrued interest converted into common stock shares	479,667
February 2015 Convertible Notes
Debt Instrument [Line Items]
Convertible promissory note		$ 1,000,000
Unpaid principal and accrued interest converted into common stock shares	158,852
Araxes Asset Purchase Agreement
Debt Instrument [Line Items]
Convertible promissory note					$ 500,000
Unpaid principal and accrued interest converted into common stock shares	80,293
Araxes Pharma LLC
Debt Instrument [Line Items]
Convertible promissory note						$ 2,000,000
Unpaid principal and accrued interest converted into common stock shares	326,443
Certain Officers and Certain Officer's Related Parties \| January 2015 Convertible Notes
Debt Instrument [Line Items]
Convertible promissory note				$ 710,000

License Agreements - Additional Information (Detail) - USD ($)					12 Months Ended
	Mar. 06, 2015	Dec. 23, 2014	Dec. 22, 2014	Dec. 18, 2014	Dec. 31, 2015	Dec. 31, 2014
License Agreements [Line Items]
License agreements with Janssen, Michigan, and UCSF			$ 81,700,000
Convertible notes payable, related party						$ 493,000
Araxes Asset Purchase Agreement
License Agreements [Line Items]
Convertible notes payable, related party		$ 500,000
Contingent Milestone Payables		9,700,000
Common Stock
License Agreements [Line Items]
Common stock, shares issued					79,000
The University of Michigan License Agreement
License Agreements [Line Items]
Agreement termination written notice			90 days
Agreement termination notice period in event of material breach			60 days
License agreement date			Dec. 22, 2014
Common stock, shares issued, Fair Value	$ 500,000
Agreement termination period due to payment failure			30 days
The University of Michigan License Agreement \| Common Stock
License Agreements [Line Items]
Common stock, shares issued	79,113
Janssen License Agreement
License Agreements [Line Items]
Agreement termination written notice				180 days
Agreement termination notice period in event of material breach				45 days
Initiation of Certain Development Activities
License Agreements [Line Items]
License agreements with Janssen, Michigan, and UCSF			$ 1,200,000
Specified Regulatory Approvals
License Agreements [Line Items]
License agreements with Janssen, Michigan, and UCSF			30,500,000
Specified Levels of Product Sales
License Agreements [Line Items]
License agreements with Janssen, Michigan, and UCSF			$ 50,000,000
Initiation of Certain Development Activities \| Araxes Asset Purchase Agreement
License Agreements [Line Items]
License agreements with Janssen, Michigan, and UCSF		8,500,000
Contingent Milestone Payables		$ 1,200,000
Up front Payment Arrangement \| Janssen License Agreement
License Agreements [Line Items]
Upfront license expense				$ 1,000,000

Commitments and Contingencies - Additional Information (Detail)					4 Months Ended	12 Months Ended
	Aug. 01, 2015 USD ($) ft²	Feb. 15, 2015 USD ($)	Dec. 18, 2014 USD ($)	Aug. 29, 2014 USD ($)	Dec. 31, 2014 USD ($)	Dec. 31, 2015 USD ($)	Aug. 31, 2014
Loss Contingencies [Line Items]
Rent expense					$ 27,000	$ 267,000
Commitment to provide charitable contribution					285,000
Commitment to provide charitable contribution, description						We are obligated to make a charitable gift of $285,000 to the Leukemia and Lymphoma Society in connection with the Michigan agreement described in Note 9 to be paid in three equal parts: the first part was due and paid in January 2015, the second part was due and paid in January 2016 and the final part is due in January 2017.
Non-current liabilities for charitable gift						$ 95,000
Accounts payable and accrued expenses					846,000	$ 4,118,000
Cambridge, Massachusetts
Loss Contingencies [Line Items]
Sublease expiration date	Aug. 01, 2020
Operating lease, area of space \| ft²	3,766
Security deposit	$ 44,000
Lease term period	60 months
Office space lease monthly rent	$ 21,000
Operating lease rate of increase in annual rent	1.40%
Total base rent payable over the lease period	$ 1,300,000
Araxes Pharma LLC
Loss Contingencies [Line Items]
Percentage of rent escalation							3.00%
Sublease expiration date						Aug. 30, 2016
Araxes Pharma LLC \| Monthly
Loss Contingencies [Line Items]
Rent expense			$ 4,820	$ 4,680
The University of Michigan Sponsored Research Agreement
Loss Contingencies [Line Items]
Sponsor of research over three- year		$ 2,700,000
Sponsored research agreement period		3 years
Sponsored research amount, expensed as incurred		$ 2,000,000
Research and development						$ 878,000
The University of Michigan License Agreement
Loss Contingencies [Line Items]
Research and development					285,000
Current liabilities for charitable gift						$ 95,000
Accounts payable and accrued expenses					190,000
Long-term liabilities					$ 95,000

Commitments and Contingencies - Future Minimum Payments Required under Facility Leases (Detail) $ in Thousands	Dec. 31, 2015 USD ($)
Leases [Abstract]
2016	$ 299
2017	263
2018	266
2019	270
2020	159
Total future minimum lease payments	$ 1,257

Stockholder's Equity - Additional Information (Detail) - USD ($)			1 Months Ended	2 Months Ended	12 Months Ended
	Nov. 05, 2015	Mar. 06, 2015	Nov. 30, 2015	Dec. 31, 2015	Dec. 31, 2015	Apr. 13, 2015	Dec. 31, 2014
Stockholders' Equity Note [Abstract]
Common stock, shares issued	6,883,467
Common stock, issued price per share	$ 8.00
Proceeds from issuance of common stock, net			$ 50,300,000	$ 50,300,000	$ 97,870,000
Common stock, shares authorized				200,000,000	200,000,000	200,000,000	100,000,000
Common stock, par value		$ 0.0001		$ 0.0001	$ 0.0001	$ 0.0001	$ 0.0001
Preferred stock, shares authorized				10,000,000	10,000,000	10,000,000	10,000,000
Preferred stock, par value				$ 0.0001	$ 0.0001	$ 0.0001	$ 0.0001
Common Stock
Stockholders' Equity Note [Abstract]
Common stock, shares issued					15,164,000
Private Placement
Stockholders' Equity Note [Abstract]
Common stock, shares issued		9,485,566
Common stock, issued price per share		$ 6.32
Financing fees		$ 4,100,000
Conversion of common stock		7,500,000
Convertible promissory notes accrued interest		115,000
Payments for merger related costs		568,000
Proceeds from issuance of common stock, net		$ 55,800,000
Private Placement \| Common Stock
Stockholders' Equity Note [Abstract]
Conversion of convertible promissory notes and accrued interest, Shares		1,204,870

Equity Incentive Plan - Additional Information (Detail) - USD ($)		4 Months Ended	12 Months Ended
	Jan. 01, 2016	Dec. 31, 2014	Dec. 31, 2015	Aug. 31, 2014
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation expense		$ 237,000	$ 2,259,000
Number of shares, subject to repurchase		4,533,000	3,232,350
Employee Stock Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock options granted		0	630,000
Share-based compensation expense		$ 0	$ 399,000
Unrecognized estimated stock option compensation expenses			$ 1,900,000
Weighted average service period			3 years 2 months 12 days
Restricted Stock Awards
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation expense		237,000	$ 1,900,000
Weighted average service period			2 years 8 months 12 days
Number of shares, subject to repurchase			2,716,515
Unrecognized Expense			$ 360,000
Restricted Stock Awards \| Non-employee
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation expense		$ 237,000	$ 1,700,000
Non Employee Awards
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares, subject to repurchase			515,835
Maximum \| Employee Stock Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period			4 years
Term of options to be granted under the Plan			10 years
Minimum \| Employee Stock Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period			3 years
2014 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares reserved for issuance				5,975,000
Common shares reserved for future issuance pursuant to future option grants			478,272
Percentage of increase in common shares reserved for future issuance pursuant to future option grants			4.00%
2014 Plan \| Restricted Stock Awards
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period			4 years
2014 Plan \| Restricted Stock With Cliff Vesting
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period			1 year
2015 Employee Stock Purchase Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common shares reserved for future issuance pursuant to future option grants			25,000
2015 Employee Stock Purchase Plan \| Employee Stock Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Additional common shares reserved for future issuance pursuant to future option grants			2,000,000
2015 Employee Stock Purchase Plan \| Maximum \| Employee Stock Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of increase in common shares reserved for future issuance pursuant to future option grants			1.00%
Subsequent Event \| 2014 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Additional common shares reserved for future issuance pursuant to future option grants	854,822
Subsequent Event \| 2015 Employee Stock Purchase Plan \| Employee Stock Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Additional common shares reserved for future issuance pursuant to future option grants	213,705

Equity Incentive Plan - Summary of Stock Option Activity (Detail) - Stock Option - USD ($) $ / shares in Units, $ in Thousands	4 Months Ended	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2015
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Granted, Number of Shares	0	630,000
Canceled/forfeited, Number of Shares		(56,000)
Outstanding, Number of Shares		574,000
Exercisable, Number of Shares		24,000
Granted, Weighted-Average Exercise Price per Share		$ 8.85
Canceled/forfeited, Weighted-Average Exercise Price per Share		6.32
Outstanding, Weighted-Average Exercise Price per Share		9.10
Exercisable, Weighted-Average Exercise Price per Share		$ 6.62
Outstanding, Weighted -Average Remaining Contractual Term (years)		9 years 1 month 6 days
Exercisable, Weighted -Average Remaining Contractual Term (years)		2 years 3 months 18 days
Outstanding, Aggregate Intrinsic Value		$ 761
Exercisable, Aggregate Intrinsic Value		$ 48

Equity Incentive Plan - Summary of Assumptions used to Estimate the Fair Value of Stock Options Under Black-Scholes Option Pricing Model (Detail)	12 Months Ended
	Dec. 31, 2015 $ / shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted-average grant date fair value per share	$ 4.16
Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected volatility	70.80%
Expected term (in years)	6 years
Risk free interest rate	1.70%
Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected volatility	72.80%
Expected term (in years)	6 years 29 days
Risk free interest rate	1.80%

Equity Incentive Plan - Summary of Restricted Stock Awards Activity (Detail) - Restricted Stock Awards - $ / shares shares in Thousands	4 Months Ended	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2015
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Beginning Balance, Number of Shares		4,533
Granted, Number of Shares	4,944
Vested, Number of Shares	(411)	(1,279)
Forfeited, Number of Shares		(21)
Ending Balance, Number of Shares	4,533	3,233
Vested, Number of Shares		1,690
Beginning Balance, Weighted-Average Grant Date Fair Value		$ 0.002
Granted, Weighted-Average Grant Date Fair Value	$ 0.002
Vested, Weighted-Average Grant Date Fair Value	0.002	0.002
Forfeited, Weighted-Average Grant Date Fair Value		0.011
Ending Balance, Weighted-Average Grant Date Fair Value	$ 0.002	0.002
Vested, Weighted-Average Grant Date Fair Value		$ 0.002
Employee
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Beginning Balance, Number of Shares		3,774
Granted, Number of Shares	4,096
Vested, Number of Shares	(322)	(1,036)
Forfeited, Number of Shares		(21)
Ending Balance, Number of Shares	3,774	2,717
Vested, Number of Shares		1,358
Non-employee
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Beginning Balance, Number of Shares		759
Granted, Number of Shares	848
Vested, Number of Shares	(89)	(243)
Ending Balance, Number of Shares	759	516
Vested, Number of Shares		332

Equity Incentive Plan - Summary of Share-based Compensation Expense (Detail) - USD ($) $ in Thousands	4 Months Ended	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2015
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation expense	$ 237	$ 2,259
Research and development
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation expense	233	1,916
General and administrative
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation expense	$ 4	$ 343

Related Party Transactions - Additional Information (Detail) - USD ($)			4 Months Ended	12 Months Ended
	Dec. 18, 2014	Oct. 01, 2014	Dec. 31, 2014	Dec. 31, 2015	Mar. 06, 2015	Jan. 12, 2015	Dec. 23, 2014	Oct. 08, 2014
Related Party Transaction [Line Items]
Rent expense related to office space sublease			$ 27,000	$ 267,000
Accounts receivable, related party			30,000	$ 430,000
Araxes Asset Purchase Agreement
Related Party Transaction [Line Items]
Convertible promissory note							$ 500,000
Unpaid principal and accrued interest converted into common stock shares					80,293
Araxes Pharma LLC
Related Party Transaction [Line Items]
Convertible promissory note								$ 2,000,000
Unpaid principal and accrued interest converted into common stock shares					326,443
Sublease expiration date				Aug. 30, 2016
Management Fee, Description				We have a management services agreement with Araxes under which Araxes pays us a fixed monthly fee of $100,000 for management services. In addition, the agreement allows for Araxes to reimburse us an amount equal to the number of full time equivalents, or FTE, performing research and development services for Araxes, at an annual FTE rate of $350,000, plus actual expenses as reasonably incurred. The initial term of this agreement expired on December 31, 2015 but, pursuant to the terms of the agreement, renews automatically for additional consecutive one-year periods. The agreement may be terminated by either party with a notice of at least 30 days prior to the expiration of the renewal term.
Management service agreement, fixed		$ 100,000
Management service agreement, full time equivalents performing research and development services		$ 350,000
Agreement expiration date		Dec. 31, 2015
Agreement termination notice period				30 days
Amount received on research and development services			30,000	$ 330,000
Accounts receivable, related party			30,000	430,000
Director
Related Party Transaction [Line Items]
Office space sublease monthly rent	$ 5,000
Rent expense related to office space sublease			15,000	58,000
Sublease expiration date	Aug. 30, 2016
Wellspring Biosciences LLC
Related Party Transaction [Line Items]
Agreement expiration date		Dec. 31, 2015
Agreement termination notice period		30 days
Research and development services expense at full time equivalents rate		$ 400,000
Research and development, related party			130,000	4,100,000
Accrued expenses, related party			$ 0	$ 911,000
January 2015 Convertible Notes
Related Party Transaction [Line Items]
Convertible promissory note						$ 3,000,000
Unpaid principal and accrued interest converted into common stock shares					479,667
January 2015 Convertible Notes \| Certain Officers and Certain Officer's Related Parties
Related Party Transaction [Line Items]
Convertible promissory note						$ 710,000

Income Taxes - Additional Information (Detail) - USD ($)	4 Months Ended	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2015
Significant Components Of Deferred Tax Assets And Liabilities [Line Items]
Effective federal statutory income tax rate, Percent	34.00%	34.00%
Loss carryforwards begin to expire		2034
Increase in valuation allowance		$ 8,900,000
Income tax examination, likelihood of unfavorable settlement		An uncertain tax position will not be recognized if it has less than a 50% likelihood of being sustained.
Unrecognized interest or penalties	$ 0	$ 0
Domestic Tax Authority
Significant Components Of Deferred Tax Assets And Liabilities [Line Items]
Net operating loss		19,500,000
Research credit carryforwards		$ 514,000
Credit carry forward begin to expire		2034
State and Local Jurisdiction
Significant Components Of Deferred Tax Assets And Liabilities [Line Items]
Net operating loss		$ 23,500,000
Research credit carryforwards		301,000
State and Local Jurisdiction \| Expire in 2034
Significant Components Of Deferred Tax Assets And Liabilities [Line Items]
Net operating loss		$ 23,400,000
Credit carry forward begin to expire		2034
State and Local Jurisdiction \| Expire in 2030
Significant Components Of Deferred Tax Assets And Liabilities [Line Items]
Net operating loss		$ 66,000
Credit carry forward begin to expire		2030

Income Taxes - Schedule of Effective Income Tax Rate Reconciliation (Detail) - USD ($) $ in Thousands	4 Months Ended	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Income taxes at statutory federal rate	$ (1,248)	$ (7,693)
State income tax, net of federal benefit	(225)	(1,412)
Share-based compensation	80	712
Research and development tax credits	(28)	(544)
Other	13	29
Valuation allowance	1,408	8,908
Income tax expense	$ 0	$ 0

Income Taxes - Components of Deferred Tax Assets (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Deferred tax assets
Net operating loss carryforwards	$ 7,975	$ 442
Intangibles	999	732
Research and development tax credit carryforwards	573	28
Accruals	662	205
Other	106	1
Total deferred tax assets	10,315	1,408
Less valuation allowance	(10,315)	(1,408)
Net deferred tax assets	$ 0	$ 0

Income Taxes - Schedule of Activity Related to Unrecognized Tax Benefits (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2015 USD ($)
Income Tax Disclosure [Abstract]
Increases from tax positions taken in the current year	$ 167
Gross unrecognized tax benefits at the end of the year	$ 167