Stock-based Compensation (Tables)

6 Months Ended

Jun. 30, 2013

Stock-based Compensation Expense

The stock-based compensation expense related to all of our stock-based awards and employee stock purchases for the three and six months ended June 30, 2013 and 2012 is as follows (in thousands):

	Three Months Ended June 30,				Six Months Ended June 30,
	2013		2012		2013		2012
Cost of net revenues	$	637	$	457	$	1,217	$	920
Sales and marketing	2,012		1,447		3,023		2,618
General and administrative	3,556		2,493		7,483		4,922
Research and development	1,060		882		1,952		1,682
Total stock-based compensation expense	$	7,265	$	5,279	$	13,675	$	10,142

Stock Option Activity

Activity for the six month period ended June 30, 2013 under the stock option plans is set forth below (in thousands, except years and per share amounts):

	Stock Options Number of Shares Underlying Stock Options		Weighted Average Exercise Price per Share		Weighted Average Remaining Contractual Term	Aggregate Intrinsic Value
					(in years )
Outstanding as of December 31, 2012	3,276
Granted	—
Exercised	(1,181	)
Cancelled or expired	(72	)
Outstanding as of June 30, 2013	2,023		$	15.51	3.87	$	43,561
Vested and expected to vest at June 30, 2013	2,023		$	15.51	3.87	$	43,561
Exercisable at June 30, 2013	1,731		$	14.95	3.81	$	38,241

^[1]

Restricted Stock Units (RSUs)

Summary Of Nonvested Shares

A summary of the RSU activity for the six months ended June 30, 2013 is as follows (in thousands, except years):

	Number of Shares Underlying RSUs		Weighted Remaining Vesting Period	Aggregate Intrinsic Value
			(in years)
Nonvested as of December 31, 2012	1,500
Granted	956
Vested and released	(490	)
Forfeited	(83	)
Nonvested as of June 30, 2013	1,883		1.73	$	69,747

Market Performance Based Restricted Stock Units

Summary Of Nonvested Shares

The following table summarizes the MSU activity for the six months ended June 30, 2013 (in thousands, except years):

	Number of Shares Underlying MSUs		Weighted Average Remaining Vesting Period	Aggregate Intrinsic Value
			(in years )
Nonvested as of December 31, 2012	266
Granted	225
Vested and released	(79	)
Forfeited	(43	)
Nonvested as of June 30, 2013	369		2.08	$	13,676

[1] There were no stock options granted during the three and six months ended June 30, 2013 and 2012.