Accelerate vesting percentage.

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- Definition

On January 1 of each year from January 1, 2015 through /January 1, 2024, the number of shares reserved for issuance under the 2014 Equity Incentive Plan automatically increases by an amount of shares which is calculated as 3% of the shares of capital stock outstanding on the preceding December 31.

+ References

No definition available.

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- Definition

Number of incentive stock options that may be granted after the tenth anniversary of the 2014 Equity Incentive Plan.

+ References

No definition available.

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- Definition

Share based compensation arrangement by share based payment award options outstanding as re-measured during the vesting period of each tranche weighted average fair value.

+ References

No definition available.

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- Definition

Share based compensation arrangement by share based payment award plan modification remaining term options exercisable period.

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No definition available.

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- Definition

Number of stock options for which the exercise period was extended.

+ References

No definition available.

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
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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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
-Paragraph 2
-Subparagraph (i)
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- Definition

Unrecognized cost of unvested options awarded to employees as compensation.

+ References

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- Definition

Amount of cash inflow from realized tax benefit related to deductible compensation cost reported on the entity's tax return for equity instruments in excess of the compensation cost for those instruments recognized for financial reporting purposes.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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-Section 55
-Paragraph 24
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- Definition

Amount of cash outflow for realized tax benefit related to deductible compensation cost reported on the entity's tax return for equity instruments in excess of the compensation cost for those instruments recognized for financial reporting purposes.

+ References

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
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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.

+ 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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(3)
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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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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-Paragraph 2
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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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (d)(2)
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- Definition

Gross number of share options (or share units) granted during the period.

+ References

No definition available.

+ Details

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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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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- Definition

Percentage of vesting of share-based compensation awards.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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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

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)(2)
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- Definition

Number of non-vested options outstanding.

+ References

No definition available.

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- Definition

Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Stock-Based Compensation - Additional Information (Detail) - USD ($)			9 Months Ended	12 Months Ended
	Aug. 15, 2017	Jan. 01, 2016	Sep. 30, 2014	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Jan. 01, 2018	Jan. 01, 2017	Jan. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value of options vested				$ 5,303,000	$ 3,589,000	$ 2,489,000
Intrinsic value of options exercised				$ 2,285,000	$ 126,000	$ 1,748,000
Options granted				1,328,500	1,078,000	774,000
Fair value of options granted				$ 11.46	$ 4.28	$ 7.17
Compensation expense not yet recognized				$ 15,913,000
Weighted average period of compensation expense not yet recognized				2 years 11 months 15 days
Excess tax benefits from stock option activity or stock-based compensation expense recognized in cash flows from operations				$ 0	$ 0	$ 0
Excess tax benefits from stock option activity or stock-based compensation expense recognized in cash flows from financing activities				0	$ 0	$ 0
ASU 2016-09 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Cumulative-effect adjustment to stockholders' equity								$ 45,000
Nonemployee Options [Member] \| Modified Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unvested shares outstanding as of modification date	98,771
Accelerate vesting percentage	50.00%
Number of stock options exercise period extended	183,000
Modification period during which stock options may be exercised	6 months
Nonemployee Options [Member] \| General and Administrative [Member] \| Modified Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense				$ 537,000
Nonemployee Consultants [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average fair values of outstanding options				$ 10.16	$ 4.81	$ 10.05
2014 Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of stock options that may be granted after the tenth anniversary of the 2014 Plan				0
Annual increases in number of shares reserved for issuance as a percentage of shares of capital stock outstanding through January 1, 2024						3.00%
Share-based compensation arrangement by share-based payment award, number of shares authorized								3,920,613
Options granted				1,328,500
2014 Equity Incentive Plan [Member] \| Subsequent Event [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, number of shares authorized							4,900,481
2014 Equity Incentive Plan [Member] \| Share-Based Compensation Award, Tranche One [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of vested shares on first anniversary of grant date				25.00%
2014 Equity Incentive Plan [Member] \| Share-based Compensation Award, Tranche Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of awards granted				36 months
2014 Equity Incentive Plan [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Term of awards granted				10 years
2014 Equity Incentive Plan [Member] \| Incentive Stock Options [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, number of shares authorized						30,000,000
2014 Equity Incentive Plan [Member] \| Employees [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of awards granted		4 years
2004 Stock Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares available for future issuance			0						0
2004 Stock Incentive Plan [Member] \| Share-Based Compensation Award, Tranche One [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of vested shares on first anniversary of grant date			25.00%
2004 Stock Incentive Plan [Member] \| Share-based Compensation Award, Tranche Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of awards granted			36 months
2004 Stock Incentive Plan [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Term of awards granted			10 years