Description of Business and Basis of Presentation (Tables)

9 Months Ended

Sep. 30, 2013

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Schedule of computation of basic and diluted net income (loss) per share

The following table sets forth the computation of basic and diluted net income per share (in thousands, except per share data):

	Three Months Ended				Nine Months Ended
	September 30,				September 30,
			2012				2012
	2013		(Restated)		2013		(Restated)
Numerator
Net income	$	6,027	$	5,228	$	9,154	$	4,307
Denominator
Weighted-average common shares outstanding	28,884		28,736		28,857		28,511
Effect of potentially dilutive securities:
Options to purchase common stock	35		8		17		153
Restricted stock awards	1		3		4		11
Restricted stock unit awards	20		—		5		3
Employee stock purchase plan	—		1		—		17
Weighted-average common shares outstanding, assuming dilution	28,940		28,748		28,883		28,695
Net income per share
Basic	$	0.21	$	0.18	$	0.32	$	0.15
Diluted	$	0.21	$	0.18	$	0.32	$	0.15

Schedule of instruments convertible into common shares that are not included in the denominator used in the diluted net income (loss) per share calculation because to do so would be anti-dilutive

The following table summarizes instruments that may be convertible into common shares that are not included in the denominator used in the diluted net income per share calculation because to do so would be anti-dilutive (in thousands):

	Three Months Ended		Nine Months Ended
	September 30,		September 30,
	2013	2012	2013	2012
Outstanding options to purchase common stock	543	920	743	549
Unvested restricted stock awards	455	337	455	338
Unvested restricted stock unit awards	—	20	13	17