Stockholders' Equity - Stock Repurchase Plan (Details) - 2015 And 2017 Stock Repurchase Plans - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended	3 Months Ended	43 Months Ended
	Aug. 03, 2018	Jun. 30, 2018	Aug. 03, 2018	Oct. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Remaining authorized repurchase amount		$ 240,607		$ 400,294
Repurchased stock value		$ 10,000
Shares repurchased (in shares)		85,792
Repurchased stock acquired average cost per share (in dollars per share)		$ 116.56
Subsequent Event
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Remaining authorized repurchase amount	$ 207,464		$ 207,464
Repurchased stock value	$ 33,143		$ 327,535
Shares repurchased (in shares)	294,758		4,103,052
Repurchased stock acquired average cost per share (in dollars per share)	$ 112.44		$ 79.83