Stock-Based Compensation - Summary of Company's Stock Option Plans (Detail) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Number of Options, Outstanding at beginning of year	1,019,684
Number of Options, Granted	657,500
Number of Options, Exercised	0
Number of Options, Forfeited	(161,125)
Number of Options, Outstanding at end of year	1,516,059	1,019,684
Number of Options, Vested	550,408
Number of Options, Unvested	965,651
Number of Options, Vested or expected to vest, December 31, 2016	1,516,059
Number of Options, Exercisable, December 31, 2016	550,408
Weighted-Average Exercise Price, Outstanding at beginning of year	$ 7.30
Weighted-Average Exercise Price, Granted	7.56
Weighted-Average Exercise Price, Forfeited	8.76
Weighted-Average Exercise Price, Outstanding at end of year	7.25	$ 7.30
Weighted-Average Exercise Price, Vested	7.44
Weighted-Average Exercise Price, Unvested	7.15
Weighted-Average Exercise Price, Vested or expected to vest, December 31, 2016	7.25
Weighted-Average Exercise Price, Exercisable, December 31, 2016	$ 7.44
Weighted-Average Remaining Contractual Life, Outstanding	5 years 2 months 9 days	5 years 5 months 16 days
Weighted-Average Remaining Contractual Life, Vested	4 years 29 days
Weighted-Average Remaining Contractual Life, Unvested	5 years 9 months 26 days
Weighted-Average Remaining Contractual Life, Vested or expected to vest, December 31, 2016	5 years 2 months 9 days
Weighted-Average Remaining Contractual Life, Exercisable, December 31, 2016	4 years 29 days
Aggregate Intrinsic Value, Outstanding	$ 3,607
Aggregate Intrinsic Value, Exercised		$ 21,436	$ 10,161
Aggregate Intrinsic Value, Outstanding	48	$ 3,607
Aggregate Intrinsic Value, Vested	31
Aggregate Intrinsic Value, Unvested	17
Aggregate Intrinsic Value, Vested or expected to vest, December 31, 2016	48
Aggregate Intrinsic Value, Exercisable, December 31, 2016	$ 31