Stockholders' Equity - Schedule of Stock Repurchases (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Class of Stock [Line Items]
Total cost	$ 55,738	$ 168,094	$ 21,489
2016 Stock Repurchase Program
Class of Stock [Line Items]
Shares of common stock repurchased and retired (in shares)	756	4,674	452
Average price per share (in dollars per share)	$ 53.88	$ 35.94	$ 41.06
Total cost	$ 40,722	$ 168,001	$ 18,577