VARIABLE INTEREST ENTITIES - Information Regarding Activity in Alternative Energy Partnerships (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2021	Jun. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Variable Interest Entity [Line Items]
Gain (loss) on investments in alternative energy partnerships	$ 1,785	$ 829	$ 1,430	$ (1,016)	$ (308)
Variable Interest Entity, Not Primary Beneficiary
Variable Interest Entity [Line Items]
Fundings	0		0	0	3,631
Cash distribution from investment	657		611	1,765	1,612
Gain (loss) on investments in alternative energy partnerships	1,785		1,430	(1,016)	(308)
Income tax credits recognized	0		0	0	0
Tax expense (benefit) recognized from HLBV application	$ 491		$ 185	$ (280)	$ (111)

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