Organization and Summary of Significant Accounting Policies - Computation of Basic and Diluted Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Basic:
Net loss	$ (10,232)	$ (16,730)	$ (16,833)	$ (15,824)
Basic weighted shares outstanding (in shares)	72,921	71,861	72,754	71,563
Net loss per share (in dollars per share)	$ (0.14)	$ (0.23)	$ (0.23)	$ (0.22)
Diluted:
Net loss	$ (10,232)	$ (16,730)	$ (16,833)	$ (15,824)
Basic weighted shares outstanding (in shares)	72,921	71,861	72,754	71,563
Effect of dilutive securities:
Stock options, ESPP, restricted stock units, restricted stock awards and convertible senior notes (in shares)	0	0	0	0
Diluted weighted shares outstanding (in shares)	72,921	71,861	72,754	71,563
Net loss per share (in dollars per share)	$ (0.14)	$ (0.23)	$ (0.23)	$ (0.22)