Stockholders' Equity - Summary of Stock Option Activity (Detail) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2013
Equity [Abstract]
Number of Shares, Beginning Balance	4,032,433
Number of Shares, Granted	497,580
Number of Shares, Exercised	(1,788,274)
Number of Shares, Expired	(187)
Number of Shares, Forfeited	(37,921)
Number of Shares, Ending Balance	2,703,631
Number of Shares, Exercisable	1,695,968
Number of Shares, Vested and expected to vest	2,636,118
Weighted Average Exercise Price, Beginning Balance	$ 10.00
Weighted Average Exercise Price, Granted	$ 22.35
Weighted Average Exercise Price, Exercised	$ 9.01
Weighted Average Exercise Price, Expired	$ 11.48
Weighted Average Exercise Price, Forfeited	$ 16.16
Weighted Average Exercise Price, Ending Balance	$ 12.84
Weighted Average Exercise Price, Exercisable	$ 10.02
Weighted Average Exercise Price, Vested and expected to vest	$ 12.72
Aggregate Intrinsic Value, Outstanding	$ 51,421
Aggregate Intrinsic Value, Exercisable	37,044
Aggregate Intrinsic Value, Vested and expected to vest	$ 50,458
Weighted Average Remaining Contractual Life, Outstanding	6 years 4 months 24 days
Weighted Average Remaining Contractual Life, Exercisable	5 years 2 months 12 days