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

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

Amount after tax of increase (decrease) to equity or (increase) decrease to net assets, resulting from the cumulative effect adjustment of a new accounting principle applied in the period of adoption.

+ References

No definition available.

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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

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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=96867065&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=96867065&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=96867065&loc=d3e5070-113901

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- Definition

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

+ References

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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

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.

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- Definition

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

+ References

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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 ($)			12 Months Ended
	Jul. 15, 2015	Jul. 14, 2015	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected dividend rate			0.00%	0.00%	0.00%
Number of common stock shares reserved for issuance			9,674,371	8,636,175
Accounting Standards Update 2016-09 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Retrospective adjustment to retained earnings			$ 8,000
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
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%
Common shares authorized to be issued during the period	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 reserved for issuance			6,493,998
Stock option grants description			The number of shares reserved for issuance under the 2015 Plan will increase automatically on January 1 of each calendar year from 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
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			1,503,770	1,392,521
Weighted-average grant date fair values of options granted			$ 1.09	$ 2.19	$ 10.51
Aggregate intrinsic value of options exercised			$ 200,000	$ 1,200,000	$ 200,000
Total grant date fair value of options vested			6,500,000	$ 6,100,000	$ 1,400,000
Total unrecognized stock-based compensation related to unvested stock options			$ 9,200,000
Weighted-average period			1 year 9 months 18 days
Common shares authorized to be issued during the period			1,214,837	1,202,324	3,400,000