Description of Business and Summary of Significant Accounting Policies (AntiDilutive) (Details) - shares
shares in Thousands
3 Months Ended 9 Months Ended
Sep. 30, 2017
Sep. 30, 2016
Sep. 30, 2017
Sep. 30, 2016
Anti-dilutive weighted-average common stock equivalents excluded from the calculation of diluted net income per share        
Total (in shares) 23 2,221 887 2,513
Options | Common Stock        
Anti-dilutive weighted-average common stock equivalents excluded from the calculation of diluted net income per share        
Total (in shares) 23 2,221 881 2,490
Restricted stock units        
Anti-dilutive weighted-average common stock equivalents excluded from the calculation of diluted net income per share        
Total (in shares)     6 23