Stockholders' Equity - Additional Information (Detail) $ / shares in Units, $ in Thousands	5 Months Ended	12 Months Ended			31 Months Ended
	May. 16, 2013 shares	Dec. 31, 2015 USD ($) purchase_period $ / shares shares	Dec. 31, 2014 USD ($) $ / shares shares	Dec. 31, 2013 USD ($) $ / shares shares	Dec. 31, 2015 USD ($) $ / shares shares
Stockholders Equity Note [Line Items]
Preferred stock, par value (usd per share) | $ / shares		$ 0.0001	$ 0.0001		$ 0.0001
Total intrinsic value of stock options exercised		$ 7,400	$ 24,500	$ 46,700
Fair value of stock options vested		100	700	3,700
Excess tax benefit from share-based payment arrangements		500
Employees' taxes paid upon the vesting of restricted stock units		$ (20,716)	(7,608)	(4,363)
Employee Stock Purchase Plan, Duration Of Offering Period		24 months
Number of offering periods | purchase_period		4
Stock-based compensation expense		$ 52,943	39,823	26,438
Stockholder Rights Plan
Stockholders Equity Note [Line Items]
Number of shares called by each right (shares) | shares		0.001			0.001
Amended And Restated 2005 Stock Incentive Plan
Stockholders Equity Note [Line Items]
Shares reserved for issuance | shares		4,869,639			4,869,639
2001 Purchase Plan
Stockholders Equity Note [Line Items]
Employee stock purchase plan, purchase price as percentage of fair market value of common stock		85.00%
Restricted Stock Units (RSUs)
Stockholders Equity Note [Line Items]
Vested rand released in period, Total intrinsic value		$ 45,900	38,900	20,300
Vested in period, Fair value		30,000	22,000	13,200
Total unamortized compensation cost		$ 65,200			$ 65,200
Weighted average period of total unamortized cost		2 years
Restricted stock units, shares vested and released (shares) | shares		781,232.000
Restricted stock units, shares withheld for tax payments | shares		269,634
Restricted stock units, net issuance | shares		511,598
Stock Options | Incentive Plan 2005
Stockholders Equity Note [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights		25% vesting one year from the date of grant and 1/48th each month thereafter
Market Performance Based Restricted Stock Units
Stockholders Equity Note [Line Items]
Vested rand released in period, Total intrinsic value		$ 9,200	2,900	3,200
Vested in period, Fair value		4,900	$ 1,200	$ 1,500
Total unamortized compensation cost		$ 14,000			$ 14,000
Weighted average period of total unamortized cost		1 year 3 months 18 days
Restricted stock units, shares vested and released (shares) | shares		161,502.000
Restricted stock units, shares withheld for tax payments | shares		83,842
Restricted stock units, net issuance | shares		77,660
Market Performance Based Restricted Stock Units | Minimum
Stockholders Equity Note [Line Items]
Stock incentive plan, vesting period		2 years
Market Performance Based Restricted Stock Units | Maximum
Stockholders Equity Note [Line Items]
Stock incentive plan, vesting period		3 years
Percentage of market-performance based restricted stock units eligible to vest over the vesting period		150.00%
Employee Stock Incentive Plan 2005 [Member]
Stockholders Equity Note [Line Items]
Shares counted against authorized maximum per share awared	1.5				1.9
Number of shares available for grant (shares) | shares	23,283,379
Employee Stock Purchase Plan 2010
Stockholders Equity Note [Line Items]
Employee stock purchase plan, shares issued | shares		230,078	247,343	288,675
Weighted average exercise price (usd per share) | $ / shares		$ 36.66	$ 29.24	$ 21.96
Number of shares available for grant (shares) | shares		1,133,749			1,133,749
Employee Stock Purchase Plan 2010 | Maximum
Stockholders Equity Note [Line Items]
Maximum number of shares available | shares		2,400,000
Employee Stock Purchase Plan
Stockholders Equity Note [Line Items]
Total unamortized compensation cost		$ 1,900			$ 1,900
Weighted average period of total unamortized cost		6 months
Stock-based compensation expense		$ 4,100	$ 2,600	$ 3,400
Monthly Vesting | Stock Options | Incentive Plan 2005
Stockholders Equity Note [Line Items]
Stock incentive plan, vesting percentage		2.08%