Stockholders' Equity and Stock-based Compensation (Common Stock and Preferred Stock) (Details) - $ / shares	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Oct. 03, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options and RSUs outstanding under equity incentive plans	2,866,675	3,429,309	4,495,891	7,527,680
Total shares reserved for future issuance	9,325,223
Preferred Stock
Preferred stock, shares authorized	20,000,000	20,000,000
Preferred stock, par value per share (in dollars per share)	$ 0.001	$ 0.001
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Preferred Stock
Preferred Stock
Preferred stock, shares authorized					20,000,000
Preferred stock, par value per share (in dollars per share)					$ 0.001
2000 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options and RSUs outstanding under equity incentive plans	157,385
2012 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options and RSUs outstanding under equity incentive plans	3,924,108
Shares available for future grants under an equity incentive plan	5,243,730