Description of Business and Summary of Significant Accounting Policies (AntiDilutive) (Details) - shares shares in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Anti-dilutive weighted-average common stock equivalents excluded from the calculation of diluted net income per share
Total (in shares)	1,111	2,555	1,319	2,659
Options | Common Stock
Anti-dilutive weighted-average common stock equivalents excluded from the calculation of diluted net income per share
Total (in shares)	1,096	2,553	1,310	2,624
Restricted stock units
Anti-dilutive weighted-average common stock equivalents excluded from the calculation of diluted net income per share
Total (in shares)	15	2	9	35