Stockholder's Equity and Stock Based Compensation (Detail 2) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2015
Additional information
Total stock-based compensation expense	$ 39,182	$ 25,120	$ 8,075
Employee Stock Purchase Plan [Member]
Additional information
Total stock-based compensation expense	$ 1,700
RSUs
Stockholder's Equity and Stock Based Compensation
Vesting period	4 years	4 years	4 years
Additional information
Total stock-based compensation expense	$ 26,400
RSUs | Minimum
Stockholder's Equity and Stock Based Compensation
Vesting period	3 years
RSUs | Maximum
Stockholder's Equity and Stock Based Compensation
Vesting period	4 years
Stock options to purchase common stock
Stockholder's Equity and Stock Based Compensation
Awards outstanding	5,404,000	5,404,000		3,777,000
Number of Stock Options Outstanding
Balance at the beginning of the period (in shares)	5,404,000
Granted (in shares)	65,000
Exercised (in shares)	(1,292,000)
Cancelled/Forfeited (in shares)	(400,000)
Balance at the end of the period (in shares)	3,777,000	5,404,000
Exercisable at the end of the period (in shares)				3,234,000
Vested and expected to vest at the end of the period (in shares)				3,655,000
Weighted-Average Exercise Price
Balance at the beginning of the period (in dollars per share)	$ 11.55
Granted (in dollars per share)	29.12
Exercised (in dollars per share)	4.64
Cancelled/Forfeited (in dollars per share)	17.81
Balance at end of the period (in dollars per share)	$ 13.55	$ 11.55
Exercisable at the end of the period (in dollars per share)				$ 9.77
Vested and expected to vest at the end of the period (in dollars per share)				$ 13.20
Weighted-Average Remaining Contractual Life
Outstanding at the end of the period	6 years 7 months 10 days
Exercisable at the end of the period	6 years 4 months 2 days
Vested and expected to vest at the end of the period	6 years 6 months 26 days
Aggregate Intrinsic Value
Outstanding at the end of the period	$ 65,915
Exercisable at the end of the period				$ 65,435
Vested and expected to vest at the end of the period				$ 64,761
Closing stock price (in dollars per share)				$ 28.71
Additional information
Weighted average grant date fair value (in dollars per share)	$ 12.44	$ 20.72	$ 5.08
Total intrinsic value of options exercised	$ 31,938	$ 47,273	$ 38,241
Total estimated grant date fair value of options vested	13,900	$ 5,200	$ 4,200
Total stock-based compensation expense	$ 8,400
Stock options to purchase common stock | 2006 Stock Plan
Stockholder's Equity and Stock Based Compensation
Number of shares available for issuance				0
Awards outstanding	2,800,000			2,800,000
Vesting period	4 years
Number of Stock Options Outstanding
Balance at the end of the period (in shares)	2,800,000
Stock options to purchase common stock | 2013 Equity Incentive Plan
Stockholder's Equity and Stock Based Compensation
Number of shares available for issuance				9,119,341
Vesting period	4 years
Numbers of shares available for future grants				3,900,000
Additional information
Number of shares available for issuance				3,900,000
Stock options to purchase common stock | 2013 Equity Incentive Plan | Minimum
Stockholder's Equity and Stock Based Compensation
Number of shares increased annually under the plan which is available for issuance				3,250,000
Number of shares as a percentage of outstanding shares on last day of preceding fiscal year which are available for issuance				5.00%
Stock options to purchase common stock | 2013 Equity Incentive Plan | Maximum
Stockholder's Equity and Stock Based Compensation
Exercise period	10 years
Stock options to purchase common stock | Employee Stock Purchase Plan [Member]
Stockholder's Equity and Stock Based Compensation
Numbers of shares available for future grants				900,000
Additional information
Number of shares of common stock issued under the ESPP	200,000
Average purchase price of shares issued (in dollars per share)				$ 23.88
Total common stock reserved for issuance (in shares)				1,500,000
Number of shares available for issuance				900,000
Stock options to purchase common stock | Employee Stock Purchase Plan [Member] | Minimum
Stockholder's Equity and Stock Based Compensation
Number of shares increased annually under the plan which is available for issuance				650,000
Additional information
Number of shares as a percentage of outstanding shares on first day of fiscal year which are available for issuance				1.00%
Percentage of fair market value to purchase shares of common stock				85.00%
Stock options to purchase common stock | Employee Stock Purchase Plan [Member] | Maximum
Additional information
Maximum percentage of eligible compensation of employees to purchase shares of common stock				15.00%
Maximum number of shares that can be purchased by participant during an offering period	1,250