Stockholders' Equity - Additional information (Detail) $ / shares in Units, $ in Millions	3 Months Ended
Mar. 31, 2017 USD ($) shares	Feb. 21, 2017 Warrant $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Term of options granted period	10 years
Vesting period of shares	3 years
Unrecognized compensation cost related to non-vested share-based compensation awards granted \| $	$ 11.9
Unrecognized compensation cost related to non-vested share-based compensation awards granted year	2020
Stock option exercisable	2,612,869
CRG Warrants [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of common stock		1,701,583
Exercise price of warrants \| $ / shares		$ 2.38
Number of warrants type issued \| Warrant		5
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of equity instruments awarded in period	2,060,000
Fair market value of RSUs granted \| $	$ 3.7
Vesting period of options	3 years
Restricted Stock Units (RSUs) [Member] \| Time-Based [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of vesting	50.00%
Restricted Stock Units (RSUs) [Member] \| Performance-Based [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of vesting	50.00%
Employees [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of equity instruments awarded in period	615,155
Fair market value of shares granted \| $	$ 1.2
Employees [Member] \| Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of equity instruments awarded in period	420,000

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Share based compensation arrangements by share based payment award term of options granted.

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

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