Stockholders' Equity - Additional information (Detail) $ in Millions	6 Months Ended
Jun. 30, 2017 USD ($) shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost related to non-vested share-based compensation awards granted \| $	$ 10.5
Unrecognized compensation cost related to non-vested share-based compensation awards granted year	2020
Stock option exercisable	1,921,093
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of equity instruments awarded in period	2,180,000
Fair market value of RSUs granted \| $	$ 4.1
Restricted Stock Units (RSUs) [Member] \| Share-based Compensation Award, Tranche One [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of equity instruments awarded in period	2,060,000
Vesting period of shares	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%
Restricted Stock Units (RSUs) [Member] \| Share-based Compensation Award, Tranche Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of equity instruments awarded in period	120,000
Vesting period of shares	1 year
Employees [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of equity instruments awarded in period	807,503
Fair market value of shares granted \| $	$ 1.5
Term of options granted period	10 years
Vesting period of shares	3 years
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	540,000

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

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-Publisher FASB
-Name Accounting Standards Codification
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