VARIABLE INTEREST ENTITIES - Information Regarding Activity in Alternative Energy Partnerships (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Dec. 31, 2019	Mar. 31, 2019
Variable Interest Entity [Line Items]
Loss on investments in alternative energy partnerships	$ (3,052)		$ (2,587)
Variable Interest Entity, Not Primary Beneficiary
Variable Interest Entity [Line Items]
Funding transferred	3,631		0
Cash distribution from investment	454		460
Loss on investments in alternative energy partnerships	(1,905)	$ (1,039)	(1,950)
Income tax credits recognized	0		0
Tax benefit recognized from HLBV application	$ 458		$ 527

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