Stock-Based Compensation (Tables)

12 Months Ended

Dec. 31, 2015

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Schedule of Stock Based Compensation Expense

The following table summarizes the components of total stock-based compensation expense included in the Company’s consolidated statements of income for the years ended December 31, 2015, 2014 and 2013 (in thousands):

	2015			2014			2013
Cost of revenue	$	14,145		$	11,934		$	10,867
Research and development	23,927			19,341			17,472
Sales and marketing	53,542			47,570			39,290
General and administrative	35,063			33,151			28,255
Total stock-based compensation	126,677			111,996			95,884
Provision for income taxes	(49,033		)	(39,182		)	(34,829		)
Total stock-based compensation, net of taxes	$	77,644		$	72,814		$	61,055

Schedule of Stock Options Granted Black Scholes

he grant-date fair values of the Company's stock option awards granted during the years ended December 31, 2014 and 2013 were estimated using the Black-Scholes option pricing model with the following weighted-average assumptions:

	2014		2013
Expected term (in years)	4.4		4.5
Risk-free interest rate	0.8	%	0.8	%
Expected volatility	40.4	%	44.4	%
Dividend yield	—	%	—	%

Schedule of ESPP Granted Black Scholes

The grant-date fair values of the Company's ESPP awards granted during the years ended December 31, 2015, 2014 and 2013 were estimated using the Black-Scholes option pricing model with the following weighted-average assumptions:

	2015		2014		2013
Expected term (in years)	0.5		0.5		0.5
Risk-free interest rate	0.2	%	0.1	%	0.1	%
Expected volatility	28.0	%	33.5	%	42.0	%
Dividend yield	—	%	—	%	—	%

Schedule of Summary of Stock Option Activity

The following table summarizes stock option activity during the year ended December 31, 2015:

	Shares (in thousands)		Weighted Average Exercise Price		Weighted Average Remaining Contractual Term (in years)	Aggregate Intrinsic Value (in thousands)
Outstanding at January 1, 2015	2,671		$	28.65
Exercised	(1,132	)	23.40
Forfeited	(15	)	29.23
Outstanding at December 31, 2015	1,524		$	32.39	3.06	$	30,875
Exercisable at December 31, 2015	1,244		$	33.33	2.64	$	24,033
Vested or expected to vest December 31, 2015	1,498		$	32.46	3.03	$	30,225

Schedule Of Deferred Stock Units Activity

The following table summarizes the DSU activity for the year ended December 31, 2015:

	Units (in thousands)		Weighted Average Grant Date Fair Value
Outstanding at January 1, 2015	260		$	36.35
Granted	28		76.12
Vested and distributed	(142	)	34.63
Outstanding at December 31, 2015	146		$	45.42

Schedule of Restricted Stock Units by Type

The following table summarizes the different types of restricted stock units ("RSUs") granted by the Company during the years ended December 31, 2015, 2014 and 2013 (in thousands):

	December 31, 2015	December 31, 2014	December 31, 2013
RSUs with service-based vesting conditions	2,507	1,949	2,338
RSUs with performance-based vesting conditions	583	575	760
Total	3,090	2,524	3,098

Schedule of Restricted Stock Units Activity

The following table summarizes the RSU activity for the year ended December 31, 2015:

	Units (in thousands)		Weighted Average Grant Date Fair Value
Outstanding at January 1, 2015	4,542		$	48.98
Granted	3,090		69.00
Vested	(2,289	)	46.01
Forfeited	(274	)	57.37
Outstanding at December 31, 2015	5,069		$	62.20