Revenue Recognition Contract Liabilities (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Dec. 31, 2019
Revenue from Contract with Customer [Abstract]
Deferred revenue	$ 170,034	$ 157,986	$ 168,223	$ 157,986	$ 162,186	$ 168,223
Deferred incentive revenue					7,067	7,397
Customer deposits					48,375	39,101
Deferred revenue and customer deposits					$ 217,628	$ 214,721
Change in Contract with Customer, Liability [Abstract]
Beginning balance	170,034	140,734	168,223	140,130
Additions	159,142	189,138	297,254	307,497
Revenue recognized	(166,990)	(171,886)	(303,291)	(289,641)
Ending balance	$ 162,186	$ 157,986	$ 162,186	$ 157,986