Description of Business and Summary of Significant Accounting Policies (Anti-dilutive) (Details) - shares shares in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Anti-dilutive weighted-average common stock equivalents excluded from the calculation of diluted net income per share
Total (in shares)	2,179	166
Options | Common Stock
Anti-dilutive weighted-average common stock equivalents excluded from the calculation of diluted net income per share
Total (in shares)	1,065
Restricted stock units
Anti-dilutive weighted-average common stock equivalents excluded from the calculation of diluted net income per share
Total (in shares)	1,114	166