VARIABLE INTEREST ENTITIES - Information Regarding Activity in Alternative Energy Partnerships (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Mar. 31, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Variable Interest Entity [Line Items]
Gain (loss) on investments in alternative energy partnerships	$ 167	$ (1,905)	$ 355	$ (1,738)	$ (1,595)
Variable Interest Entity, Not Primary Beneficiary
Variable Interest Entity [Line Items]
Funding transferred	0		235	3,631	235
Cash distribution from investment	547		535	1,001	995
Gain (loss) on investments in alternative energy partnerships	167		355	(1,738)	(1,595)
Income tax credits recognized	0		1,723	0	1,723
Tax (expense) benefit recognized from HLBV application	$ (38)		$ 380	$ 398	$ 380

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