CONSOLIDATED FINANCIAL STATEMENT DETAILS - Allowance for Credit Loss (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Accounts Receivable, Allowance for Credit Loss [Roll Forward]
Balance at January 1	$ 26,046	$ 19,066
Current period provision for credit losses	66,081	60,090
Write-offs charged against the credit loss reserve	(56,102)	(53,208)
Recoveries collected	1,896	1,883
Balance at September 30	37,921	27,831
Revenue reserve	2,400	2,000
Allowance and reserves	$ 40,276	$ 29,800	$ 27,839