v2.4.1.9

Stockholders' Equity (Tables)

3 Months Ended

Mar. 31, 2015

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

Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]

The following table summarizes the weighted-average assumptions relating to our employee stock options:

	Three Months Ended
	March 31, 2015			March 31, 2014
Expected term in years	4.3			4.9
Volatility	40	%		45	%
Risk-free interest rate	1.5	%		1.7	%
Dividend rate	—	%		—	%

Schedule of Share-based Compensation, Stock Options, Activity [Table Text Block]

The following table summarizes the stock option activity and related information for the periods presented below (in thousands, except exercise prices and contractual life):

	Options Outstanding
	Number of Shares			Weighted- Average Exercise Price				Weighted- Average Remaining Contractual Life (Years)		Aggregate Intrinsic Value
Balance—December 31, 2014	10,702			$	14.98
Granted	269			32.79
Forfeited	(73	)		24.59
Exercised	(1,931	)		10.49
Balance—March 31, 2015	8,967			$	16.41
Options vested and expected to vest—March 31, 2015	8,924			$	16.35			2.8		$	165,975
Options exercisable—March 31, 2015	7,589			$	14.71			2.4		$	153,634

Schedule of Share-based Payment Award, Stock Options, Additional Information [Table Text Block]

Additional information related to our stock options is summarized below (in thousands, except per share amounts):

	Three Months Ended
	March 31, 2015				March 31, 2014
Weighted-average fair value per share granted	$	11.17			$	8.65
Intrinsic value of options exercised	41,003				15,321
Fair value of options vested	3,792				4,562

Schedule of Share-based Compensation, Restricted Stock Units Award Activity [Table Text Block]

The following table summarizes the activity and related information for RSUs for the periods presented below (in thousands, except per share amounts):

	Restricted Stock Units Outstanding
	Number of Shares			Weighted-Average Grant-Date-Fair Value per Share
Balance—December 31, 2014	6,291			$	22.93
Granted	2,492			32.96
Forfeited	(198	)		26.36
Vested	(670	)		22.01
Balance—March 31, 2015	7,915			$	26.18
RSUs expected to vest—March 31, 2015	7,450			$	26.02

Schedule of Share-based Compensation, Shares Withheld for Taxes [Table Text Block]

The following summarizes the number and value of the shares withheld for employee taxes (in thousands):

	Three Months Ended
	March 31, 2015				March 31, 2014
Shares withheld for taxes	221				171
Amount withheld for taxes	$	6,600			$	3,633

Schedule of Share-based Payment Award, Equity Instruments Other than Options, Valuation Assumptions [Table Text Block]

The following table summarizes the weighted-average assumptions relating to our PSUs granted to our executive officers:

	Three Months Ended
	March 31, 2015			March 31, 2014
Expected term in years	3.0			3.0
Volatility	38	%		48	%
Risk-free interest rate	1.1	%		0.7	%
Dividend rate	—	%		—	%

Share-based Compensation, Performance Shares Award Activity [Table Text Block]

The following table summarizes the activity and related information for PSUs for the periods presented below (in thousands, except per share amounts):

	Three Months Ended
	March 31, 2015				March 31, 2014
Shares granted to executive officers and employees	206				25
Weighted-average fair value per share granted	$	34.86			$	22.44

Schedule of Share-based Payment Award, Employee Stock Purchase Plan, Valuation Assumptions [Table Text Block]

In determining the fair value of our ESPP, we use the Black-Scholes option pricing model that employs the following weighted-average assumptions:

	Three Months Ended
	March 31, 2015			March 31, 2014
Expected term in years	0.5			0.5
Volatility	28	%		37	%
Risk-free interest rate	0.1	%		0.1	%
Dividend rate	—	%		—	%

Schedule of Share-based Payment Award Employee Stock Purchase Plan Additional Information [Table Text Block]

Additional information related to the ESPP is provided below (in thousands, except per share amounts):

	Three Months Ended
	March 31, 2015				March 31, 2014
Weighted-average fair value per share granted	$	7.56			$	5.76
Shares issued under the ESPP	427				424
Weighted-average price per share issued	$	21.34			$	17.18

Schedule of Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Table Text Block]

Stock-based compensation expense is included in costs and expenses as follows (in thousands):

	Three Months Ended
	March 31, 2015				March 31, 2014
Cost of product revenue	$	140			$	113
Cost of service revenue	1,632				1,329
Research and development	5,157				3,882
Sales and marketing	9,307				5,746
General and administrative	2,686				1,860
Total stock-based compensation expense	$	18,922			$	12,930

Schedule of Employee Service Share based Compensation Allocation of Recognized Period Costs by Award Type [Table Text Block]

The following table summarizes stock-based compensation expense by award type (in thousands):

	Three Months Ended
	March 31, 2015				March 31, 2014
Stock options	$	3,455			$	4,692
RSUs (including PSUs)	14,292				7,363
ESPP	1,175				875
Total stock-based compensation expense	$	18,922			$	12,930

Income Tax Benefit from Stock Option Plans [Table Text Block]

Total income tax benefit associated with stock-based compensation that is recognized in the condensed consolidated statements of operations is as follows (in thousands):

	Three Months Ended
	March 31, 2015				March 31, 2014
Income tax benefit associated with stock-based compensation	$	3,377			$	3,349

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Income Tax Benefit from Stock Option Plans [Table Text Block]

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Schedule of Employee Service Share based Compensation Allocation of Recognized Period Costs by Award Type [Table Text Block]

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Tabular disclosure of the significant assumptions used during the year to estimate the fair value of stock options, including, but not limited to: (a) expected term of share options and similar instruments, (b) expected volatility of the entity's shares, (c) expected dividends, (d) risk-free rate(s), and (e) discount for post-vesting restrictions. Tabular disclosure of the allocation of equity-based compensation costs to a given line item on the balance sheet and income statement for the period. This may include the reporting line for the costs and the amount capitalized and expensed.

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Tabular disclosure of the allocation of equity-based compensation costs to a given line item on the balance sheet and income statement for the period. This may include the reporting line for the costs and the amount capitalized and expensed.

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Tabular disclosure of the number and weighted-average grant date fair value for restricted stock units that were outstanding at the beginning and end of the year, and the number of restricted stock units that were granted, vested, or forfeited during the year.

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Tabular disclosure of the number and weighted-average exercise prices (or conversion ratios) for share options (or share units) that were outstanding at the beginning and end of the year, vested and expected to vest, exercisable or convertible at the end of the year, and the number of share options or share units that were granted, exercised or converted, forfeited, and expired during the year.

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Tabular disclosure of the number and weighted-average grant date fair value for outstanding performance shares.

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