VARIABLE INTEREST ENTITIES - Information Regarding Activity in Alternative Energy Partnerships (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2021	Mar. 31, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Variable Interest Entity [Line Items]
Gain (loss) on investments in alternative energy partnerships	$ 829	$ (3,630)	$ 167	$ (2,801)	$ (1,738)
Variable Interest Entity, Not Primary Beneficiary
Variable Interest Entity [Line Items]
Funding transferred	0		0	0	3,631
Cash distribution from investment	570		547	1,108	1,001
Gain (loss) on investments in alternative energy partnerships	829		167	(2,801)	(1,738)
Income tax credits recognized	0		0	0	0
Tax expense (benefit) recognized from HLBV application	$ 228		$ 38	$ (770)	$ (398)

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