Description of Business and Basis of Presentation (Details 1) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Outstanding options to purchase common stock
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
Anti-dilutive, shares	895	637	807	1,031
Restricted Stock Awards
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
Anti-dilutive, shares	428	340	426	429
Restricted stock unit awards
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
Anti-dilutive, shares	57	21	57	20
Employee Stock Purchase Plan
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
Anti-dilutive, shares	0	0	0	0