Share-Based Compensation (Tables)

3 Months Ended

Mar. 31, 2016

Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]

Summary of Share-Based Compensation Expense Recognized to Statements of Operations

A summary of share-based compensation expense recognized in the Company’s condensed consolidated statements of operations follows (in thousands):

	Three Months Ended
	March 31,
	2016		2015
Cost of revenues	$	653	$	457
Research and development		1,638		1,113
Sales and marketing		2,190		1,844
General and administrative		2,256		1,333
Total share-based compensation expense	$	6,737	$	4,747

Summary of Share-Based Compensation Expense by Award Type

A summary of share-based compensation expense by award type follows (in thousands):

	Three Months Ended
	March 31,
	2016		2015
Options	$	2,547	$	2,705
Employee stock purchase plan rights		550		286
Restricted stock units		3,640		1,756
Total share-based compensation expense	$	6,737	$	4,747

Summary of Stock Option Activity Plans

A summary of option activity under all of the Company’s equity incentive plans at March 31, 2016 and changes during the period then ended is presented in the following table:

						Weighted-
	Number of			Weighted-		Average		Aggregate
	Options			Average		Contractual		Intrinsic
	Outstanding			Exercise Price		Term		Value
	(in thousands)			Per Share		(in Years)		(in thousands)
Outstanding at December 31, 2015		8,048		$	10.27		6.2	$	107,091
Granted		499			16.01
Exercised		(91	)		3.10
Canceled/Forfeited		(200	)		15.27
Outstanding at March 31, 2016		8,256		$	10.58		6.0	$	45,038
Vested and expected to vest as of March 31, 2016		7,700		$	10.22		6.0	$	44,613
Exercisable as of March 31, 2016		5,130		$	7.97		5.8	$	40,730

Weighted Average Grant Date Fair Value of Options Granted and Total Intrinsic Value of Options Exercised

The weighted average grant date fair value of options granted and the total intrinsic value of options exercised were as follows (in thousands, except weighted average grant date fair value):

	Three Months Ended March 31,
	2016		2015
Weighted average grant date fair value per share	$	6.53	$	6.53
Total intrinsic value of options exercised	$	1,463	$	3,815

Weighted Average Assumptions Used to Fair Value of Stock Options Granted

The weighted-average assumptions used in the option pricing model in the periods presented were as follows:

	Three Months Ended March 31,
	2016			2015
Expected term for employees (in years)		4.7			4.8
Expected term for non-employees (in years)		6.2			7.0
Risk-free interest rate		1.11	%		1.47	%
Expected volatility		47	%		48	%
Expected dividend yield		0	%		0	%

Summary of RSUs Activity

The 2013 Plan provides for the issuance of restricted stock units (RSUs) to employees and consultants.  RSUs issued under the 2013 Plan generally vest over four years.  A summary of activity of RSUs under the 2013 Plan at March 31, 2016 and changes during the period then ended is presented in the following table:

	Number of			Weighted-
	RSUs			Average		Aggregate
	Outstanding			Grant Date Fair		Intrinsic Value
	(in thousands)			Value Per Share		(in thousands)
Outstanding at December 31, 2015		2,288		$	16.63	$	53,972
Granted		1,088			16.28
Exercised		(175	)		15.86
Canceled/Forfeited		(79	)		16.49
Outstanding at March 31, 2016		3,122		$	16.55	$	49,196