Stock Plans (Tables)

12 Months Ended

Dec. 31, 2012

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

Stock options weighted-average assumptions

The fair value of stock options was estimated on the date of grant using the Black-Scholes valuation model with the following weighted-average assumptions:

	Year Ended December 31, 2010
Expected dividends	—
Expected volatility range	69.5	%
Risk-free interest rate range	2.4	%
Expected term/life (in years)	4.8

Aggregate stock option activity

The following table summarizes total aggregate stock option activity for the period December 31, 2011 through December 31, 2012:

	Number of Shares		Weighted Average Exercise Price		Weighted Average Remaining Contractual Term (in years)	Aggregate Intrinsic Value
Balance at December 31, 2011	1,183,659		$	11.45
Exercised	(145,703	)	7.85
Canceled	(114,200	)	14.34
Balance at December 31, 2012	923,756		$	11.67	4.62	$	261,981
Vested or expected to vest at December 31, 2012	915,451		$	11.64	4.60	$	261,049
Exercisable at December 31, 2012	807,146		$	11.53	4.31	$	221,133

Restricted stock award activity

The following table summarizes restricted stock award activity for the period December 31, 2011 through December 31, 2012 (in thousands, except for per share amounts):

Nonvested Shares	Shares		Weighted Average Grant Date Fair Value
Nonvested at December 31, 2011	262		$	17.17
Granted	255		20.60
Vested	(58	)	15.04
Forfeited	(62	)	16.61
Nonvested at December 31, 2012	397		$	19.78

Employee stock purchase plan weighted-average assumptions

	Year Ended December 31, 2012			Year Ended December 31, 2011			Year Ended December 31, 2010
Expected dividends	$	—		$	—		$	—
Stock price on valuation date	11.96			17.54			14.03
Expected volatility	71		%	41		%	54		%
Risk-free interest rate	0.10		%	0.15		%	0.21		%
Expected life (in years)	0.5			0.5			0.5
Fair value per share	$	4.16		$	4.73		$	4.78

Employee service share-based compensation cost

Compensation cost for stock options, restricted stock, restricted stock units and the ESPP is as follows (in thousands):

	Year Ended December 31, 2012		Year Ended December 31, 2011		Year Ended December 31, 2010
Stock options	$	978	$	1,317	$	1,496
Restricted stock	1,427		1,014		752
Restricted stock units	421		57		188
ESPP	262		194		191
Total stock-based compensation expense	$	3,088	$	2,582	$	2,627

Stock-based compensation cost included in cost of revenue; selling, general and administrative expense; and research and development expense is as follows (in thousands):

	Year Ended December 31, 2012		Year Ended December 31, 2011		Year Ended December 31, 2010
Cost of revenue	$	701	$	355	$	304
Selling, general and administrative	1,835		1,769		2,096
Research and development	552		458		227
Total stock-based compensation expense	$	3,088	$	2,582	$	2,627

Reservation of shares for issuance upon exercise, vesting or release of share-based compensation awards

The following table summarizes the reservation of shares under the Company's stock-based compensation plans as of December 31, 2012:

2005 Omnibus Equity Incentive Plan	1,686,687
2004 Employee Stock Purchase Plan	96,800
1999 Director Stock Option Plan	3,000
1995 Stock Option Plan	158,756
Total	1,945,243