Aggregate number of common shares reserved for future issuance.

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

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-Publisher SEC

-Name Regulation S-X (SX)

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-Section 02

-Paragraph 30

-Article 5

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- Definition

Payroll costs incurred (including equity-based compensation) that are directly related to services rendered by an entity during the reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.2(d))

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- Definition

Amount of expenses for special or contractual termination benefits provided to current employees involuntarily terminated under a benefit arrangement associated exit or disposal activities pursuant to an authorized plan. Excludes expenses related to one-time termination benefits, a discontinued operation or an asset retirement obligation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 420

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SAB TOPIC 5.P.4(b))

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-Name Accounting Standards Codification

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-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 5

-Section P

-Subsection 3, 4

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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 difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

+ References

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- Definition

Number of options outstanding, including both vested and non-vested options.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

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-Topic 718

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-Section 50

-Paragraph 2

-Subparagraph (c)(1)(i)-(ii)

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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

Weighted average remaining contractual term for fully vested and expected to vest options outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (e)(1)

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- Definition

Share based compensation arrangement by share based payment award options vested and expected to vest fair value.

+ References

No definition available.

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Equity Incentive Plans - Additional Information (Detail) - USD ($) $ in Millions		3 Months Ended	9 Months Ended
	May. 06, 2015	Jun. 30, 2015	Sep. 30, 2015	Dec. 31, 2014	Mar. 21, 2014
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock, shares issued			29,360,245	24,245,437
Co-Founder And CEO [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Separation related costs	$ 2.4
Unexercised vested and expected to vest stock options	$ 2.0
Unvested stock options expected to vest, term	12 months
Incremental payroll costs		$ 0.4
2009 Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock reserved for future issuance					0
2014 Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock reserved for future issuance			1,380,000
Percentage of common stock issued and outstanding increase annually			4.50%
Number of common stock shares subject to outstanding awards			3,503,000
Employee Stock Purchase Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of common stock issued and outstanding increase annually			1.00%
Number of shares reserved			392,000
Additional shares issued			300,000
Common stock, shares issued			29,000