SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - (Details) - USD ($)	3 Months Ended
	Mar. 31, 2021	Dec. 31, 2020	Mar. 31, 2020	Dec. 31, 2019
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Impairment charges	$ 0
Adoption of CECL standard	1,900,795,000	$ 1,850,785,000	$ 1,587,623,000	$ 1,572,252,000
Retained Earnings
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Adoption of CECL standard	$ 1,704,336,000	$ 1,643,825,000	$ 1,554,665,000	1,523,820,000
Cumulative Effect, Period of Adoption, Adjustment
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Adoption of CECL standard				(1,377,000)
Cumulative Effect, Period of Adoption, Adjustment | Retained Earnings
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Adoption of CECL standard				(1,377,000)
Accounting Standards Update 2016-13 | Cumulative Effect, Period of Adoption, Adjustment | Retained Earnings
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Adoption of CECL standard				$ (1,400,000)