Revenue Recognition - Contract Liabilities (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Change in Contract with Customer, Liability [Abstract]
Beginning balance	$ 116,255	$ 169,253	$ 135,578	$ 175,455
Additions	175,423	166,504	541,519	464,135
Revenue recognized	(179,808)	(178,713)	(565,227)	(482,546)
Ending balance	$ 111,870	$ 157,044	$ 111,870	$ 157,044