Leases - Lease Costs and Other Quantitative Information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Leases [Abstract]
Operating lease cost	$ 18,495	$ 16,605	$ 53,397	$ 50,519
Variable lease cost	3,580	4,960	11,808	14,285
Sublease rental income	(2,940)	(2,376)	(8,637)	(6,565)
Total lease cost	19,135	19,189	56,568	58,239
Operating cash flows	17,703	16,988	52,930	52,163
Right-of-use assets obtained in exchange for new operating lease liabilities	$ (814)	$ 8,783	$ 37,120	$ 267,796
Weighted average remaining lease term (in years) - Operating leases	7 years 4 months 6 days	7 years	7 years 4 months 6 days	7 years
Weighted average discount rate - Operating leases	1060.00%	870.00%	1060.00%	870.00%