Stock-Based Compensation - Summary of Company's Stock Option Plans (Detail) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Number of Options, Outstanding at beginning of year	279,198
Number of Options, Granted	312,000	88,749	104,375
Number of Options, Exercised	(6,562)
Number of Options, Forfeited	(138,952)
Number of Options, Outstanding at end of year	445,684	279,198
Number of Options, Vested	131,654
Number of Options, Unvested	314,030
Number of Options, Vested or expected to vest, December 31, 2014	445,684
Number of Options, Exercisable, December 31, 2014	131,654
Weighted-Average Exercise Price, Outstanding at beginning of year	$ 11.09
Weighted-Average Exercise Price, Granted	$ 6.74
Weighted-Average Exercise Price, Exercised	$ 5.02
Weighted-Average Exercise Price, Forfeited	$ 8.77
Weighted-Average Exercise Price, Outstanding at end of year	$ 8.28	$ 11.09
Weighted-Average Exercise Price, Vested	$ 11.76
Weighted-Average Exercise Price, Unvested	$ 6.82
Weighted-Average Exercise Price, Vested or expected to vest, December 31, 2014	$ 8.28
Weighted-Average Exercise Price, Exercisable, December 31, 2014	$ 11.76
Weighted-Average Remaining Contractual Life, Outstanding	5 years 1 month 10 days	4 years 6 months 11 days
Weighted-Average Remaining Contractual Life, Vested	2 years 11 months 27 days
Weighted-Average Remaining Contractual Life, Vested or expected to vest, December 31, 2014	5 years 1 month 10 days
Weighted-Average Remaining Contractual Life, Exercisable, December 31, 2014	2 years 11 months 27 days
Aggregate Intrinsic Value, Exercised	$ 10,161	$ 4,380	$ 0
Aggregate Intrinsic Value, Outstanding, December 31, 2014	45,625
Aggregate Intrinsic Value, Vested	14,656
Aggregate Intrinsic Value, Unvested	30,969
Aggregate Intrinsic Value, Vested or expected to vest, December 31, 2014	45,625
Aggregate Intrinsic Value, Exercisable, December 31, 2014	$ 14,656