SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Jan. 01, 2018	Dec. 31, 2017
Revenue Initial Application Period Cumulative Effect Transition [Line Items]
State tax expense	$ 2,882	$ 3,682	$ 4,147
Current tax provision	(2,278)	(485)	(1,354)
Deferred tax benefit (provision)	(14,558)	(2,668)	2,905
Income tax benefit (provision)	(16,836)	(3,153)	1,551
Deferred tax asset valuation allowance	16,206
Net deferred tax asset	0	15,117
Cumulative effect of accounting change	$ 534,297	$ 861,865	$ 1,032,165		$ 1,236,478
Accounting Standards Update 2016-16
Revenue Initial Application Period Cumulative Effect Transition [Line Items]
Cumulative effect of accounting change				$ 11,433