Stock-Based Compensation (Tables)

9 Months Ended

Sep. 30, 2014

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

Stock-Based Compensation Expense Components

The following table summarizes the components and classification of stock-based compensation expense related to stock options, restricted stock units and awards (“RSUs” and “RSAs”), performance-based restricted stock units (“PSUs”) and the 2011 ESPP for the three and nine months ended September 30, 2014 and 2013 (in thousands):

	Three Months Ended September 30,				Nine Months Ended September 30,
	2014		2013		2014		2013
Stock options	$	3,340	$	3,073	$	11,670	$	9,601
RSUs/RSAs	2,748		1,728		6,665		4,114
PSUs	—		264		—		334
ESPP	200		166		358		403
Stock-based compensation expense	$	6,288	$	5,231	$	18,693	$	14,452
Research and development	1,941		$	1,544	$	5,671	$	4,111
Sales, general and administrative	4,347		3,687		13,022		10,341
Stock-based compensation expense	$	6,288	$	5,231	$	18,693	$	14,452