Schedule II - Schedule of Valuation and Qualifying Accounts (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Valuation And Qualifying Accounts [Abstract]
Balance at Beginning of Year	$ 109,803	$ 66,131	$ 16,397
Additions, Charged Against Operations	58,044	50,893	57,285
Addition, Charged to Other Accounts	22,944
Deductions, Net Recoveries/Write-offs	(44,154)	(7,221)	(7,551)
Balance at End of Year	$ 146,637	$ 109,803	$ 66,131