Commitments and Contingencies - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Operating Lease, Right-of-Use Asset	$ 281,900		$ 281,900		$ 292,100
Operating Lease, Liability	313,400		313,400		$ 323,000
Lessee, Operating Lease, Liability, Payments, Due	$ 8,000	$ 8,100	16,100	$ 15,800
Significant change in expected future minimum lease payments since year end			$ 0