VARIABLE INTEREST ENTITIES - Information Regarding Activity in Alternative Energy Partnerships (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Jun. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Variable Interest Entity [Line Items]
Gain (loss) on investments in alternative energy partnerships	$ 1,430	$ 167	$ 940	$ (308)	$ (655)
Variable Interest Entity, Not Primary Beneficiary
Variable Interest Entity [Line Items]
Funding transferred	0		0	3,631	235
Cash distribution from investment	611		534	1,612	1,529
Gain (loss) on investments in alternative energy partnerships	1,430		940	(308)	(655)
Income tax credits recognized	0		862	0	2,585
Tax expense (benefit) recognized from HLBV application	$ 185		$ 254	$ (111)	$ (177)

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