Stockholders' Equity - Summary of the Company's Stock Options Activity (Detail) - Stock Options $ / shares in Units, shares in Thousands, $ in Thousands	9 Months Ended
	Sep. 30, 2015 USD ($) $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Number of options, Options outstanding, beginning of year | shares	1,641
Number of options, Granted | shares	0
Number of options, Exercised | shares	(504)
Number of options, Expired / terminated | shares	(8)
Number of options, Options outstanding, end of year | shares	1,129
Number of options, Options exercisable, end of year | shares	1,098
Number of options, Options expected to vest, end of year | shares	25
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract]
Weighted average exercise price, Options outstanding, beginning of year	$ 5.26
Weighted average exercise price, Granted	0.00
Weighted average exercise price, Exercised	4.96
Weighted average exercise price, Expired / terminated	8.71
Weighted average exercise price, Options outstanding, end of year	5.36
Weighted average exercise price, Options exercisable, end of year	5.37
Weighted average exercise price, Options expected to vest, end of year	$ 4.75
Weighted average remaining contractual life, Options outstanding (in years)	3 years 7 months 5 days
Weighted average remaining contractual life, Options exercisable (in years)	3 years 7 months 10 days
Weighted average remaining contractual life, Options expected to vest (in years)	3 years 3 months
Aggregate intrinsic value, Options outstanding | $	$ 18,823
Aggregate intrinsic value, Options exercisable | $	18,299
Aggregate intrinsic value, Options expected to vest | $	$ 434