Common Stock Initially Reserved For Issuance

No definition available.

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- Definition

Proceeds from stock options early exercised.

+ References

No definition available.

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- Definition

Share Based Compensation Arrangement By Share Based Payment Award Options Vested Grant Date Fair Value

+ References

No definition available.

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- Definition

Share based compensation arrangement by share based payment award shares held subject to repurchase.

+ References

No definition available.

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- Definition

Stock issued during period shares stock options early exercised.

+ References

No definition available.

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- Definition

Aggregate number of common shares reserved for future issuance.

+ References

Reference 1: 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)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

Unrecognized cost of unvested options awarded to employees as compensation.

+ References

No definition available.

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- Definition

General descriptive information regarding an arrangement under which employees and directors receive: (a) awards of equity shares, equity share options, or other equity instruments; or (b) the entity incurs liabilities to them: (1) in amounts based, at least in part, on the price of the entity's shares or other equity instruments; or (2) that require or may require settlement by issuance of the entity's shares. Such an arrangement is usually provided to employees and directors to compensate them, provide performance incentives to them, and to attract or retain their services. May also include pertinent information particular to a plan that is not elsewhere specified in the taxonomy.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5047-113901

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- Definition

Discount rate from fair value on offering date that participants pay for shares.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Number of additional shares authorized for issuance under an established share-based compensation plan.

+ References

No definition available.

+ Details

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- Definition

The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

+ References

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- Definition

Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

+ References

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

+ References

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- Definition

Maximum number of shares that may be issued in accordance with the plan as a proportion of outstanding capital stock.

+ References

No definition available.

+ Details

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- Definition

Number of share instruments newly issued under a share-based compensation plan.

+ References

+ Details

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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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Stock-Based Compensation - Additional Information (Detail) - USD ($)					1 Months Ended		3 Months Ended		9 Months Ended
	Jan. 01, 2016	Dec. 31, 2015	Jul. 15, 2015	Jul. 14, 2015	Feb. 28, 2015	Dec. 31, 2014	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of common stock shares reserved for issuance		7,746,692					8,656,561		8,656,561
Proceeds from early exercise of stock options of unvested portion										$ 13,000
2008 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of common stock shares reserved for issuance				365,535
Number of shares held by employees subject to repurchase		23,554
2008 Plan [Member] \| Executive officer [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options early exercised					13,422	103,252
Proceeds from early exercise of stock options of unvested portion		$ 23,000
2015 Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of common stock shares reserved for issuance		700,000	700,000				700,000		700,000
Stock option grants description									The number of shares initially reserved for issuance under the ESPP will increase automatically on January 1 for nine years from the first offering date by the number of shares equal to 1% of the total outstanding shares of the Company's common stock as of the immediately preceding December 31.
Percentage threshold of outstanding shares increased annually under the plan			1.00%
Maximum number of common stock shares allowed to issue under employee stock purchase plan			3,400,000
Options to purchase shares of common stock, discount percentage			15.00%
Number of common stock issued									0
2015 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of common stock shares initially reserved for issuance				3,400,000
Number of common stock shares reserved for issuance				3,765,535
Stock option grants description									The number of shares initially reserved for issuance under the 2015 Plan will increase automatically on January 1 of each calendar year 2016 through 2025 by the number of shares equal to 4% of the total outstanding shares of the Company's common stock as of the immediately preceding December 31.
Percentage threshold of outstanding shares increased annually under the plan				4.00%
Stock option life in years									10 years
Number of common stock shares reserved for issuance	1,202,324
2008 Plan and 2015 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of common stock shares reserved for issuance									1,202,324
Weighted-average grant date fair values of options granted							$ 1.26	$ 23.60	$ 2.20	$ 10.19
Aggregate intrinsic value of options exercised							$ 200,000	$ 200,000	$ 1,200,000	$ 200,000
Total grant date fair value of options vested							900,000	$ 700,000	4,400,000	$ 900,000
Total unrecognized stock-based compensation related to unvested stock options							$ 15,400,000		$ 15,400,000
Weighted-average period									2 years 9 months 18 days