Stock-based Compensation (Tables)

9 Months Ended

Sep. 30, 2017

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

Employee stock-based compensation

The following table shows a summary of the stock-based compensation expense included in the condensed consolidated statements of operations for the three and nine months ended September 30, 2017 and 2016.

	Three Months Ended				Nine Months Ended
	September 30,				September 30,
	2017		2016		2017		2016
	(in thousands)
Cost of revenues	$	532	$	516	$	1,569	$	1,318
Research and development	1,503		1,585		4,229		4,373
Sales and marketing	1,231		821		3,444		3,459
General and administrative	4,477		2,181		9,280		5,972
Total stock-based compensation	$	7,743	$	5,103	$	18,522	$	15,122

Stock option activity

A summary of the Company’s stock option activity is as follows:

	Outstanding Options		Weighted Average Exercise Price		Weighted Average Remaining Contractual Life (Years)	Aggregate Intrinsic Value
						(in thousands)
December 31, 2016	7,527,680		$	19.25	6.0	$	101,717
Granted	338,725		$	38.40
Exercised	(2,364,523	)	$	10.38
Canceled	(347,573	)	$	33.72
September 30, 2017	5,154,309		$	23.60	6.6	$	145,402
Vested and expected to vest - September 30, 2017	4,852,064		$	23.05	6.5	$	139,543
Exercisable - September 30, 2017	3,458,555		$	19.94	5.6	$	110,203

Restricted stock units activity

A summary of the Company’s RSU and RSA activity is as follows:

	Outstanding RSUs and RSAs		Weighted Average Grant Date Fair Value Per Share
December 31, 2016	587,333		$	28.85
Granted	934,439		$	38.53
Released	(239,222	)	$	32.15
Canceled	(106,522	)	$	31.80
September 30, 2017	1,176,028		$	35.60
Outstanding and expected to vest - September 30, 2017	1,010,848		$	35.58