Organization and Significant Accounting Policies - Anti-dilutive Common Stock Equivalents Not Included in Calculation of Net Income (Loss) Per Diluted Share (Details) - shares shares in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Stock options, ESPP, and RSUs	21,715	4,817	28,008
Anti-dilutive securities excluded from computation of earnings per share	21,715	4,817	28,008
Stock Options E S P P And Restricted Stock Units
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Stock options, ESPP, and RSUs	912	40	8,902
Anti-dilutive securities excluded from computation of earnings per share	912	40	8,902
Warrants [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Stock options, ESPP, and RSUs	13,253	4,777	9,553
Anti-dilutive securities excluded from computation of earnings per share	13,253	4,777	9,553
Senior Convertible Notes [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Stock options, ESPP, and RSUs	7,550		9,553
Anti-dilutive securities excluded from computation of earnings per share	7,550		9,553