Net Income (Loss) Per Share (Details)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potential Common Stock Equivalents, Outstanding	5,541,050	5,551,761	4,287,195
Outstanding common stock options [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potential Common Stock Equivalents, Outstanding	5,096,674	5,246,465	3,879,239
Outstanding warrants [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potential Common Stock Equivalents, Outstanding	34,647	34,647	133,968
Outstanding PRSUs [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potential Common Stock Equivalents, Outstanding	245,396	270,649	273,988
Outstanding RSUs [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potential Common Stock Equivalents, Outstanding	161,439	0	0
Shares To be Purchased Under The ESPP [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potential Common Stock Equivalents, Outstanding	2,894	0	0