REVENUE - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Mar. 31, 2023	Dec. 31, 2022	Sep. 30, 2022	Jun. 30, 2022	Mar. 31, 2022	Dec. 31, 2021	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2023	Mar. 31, 2022	Mar. 31, 2021
Disaggregation Of Revenue [Line Items]
Revenues	$ 21,629	$ 20,288	$ 17,560	$ 17,906	$ 22,058	$ 30,714	$ 36,510	$ 35,101	$ 77,383	$ 124,383	$ 116,840
Percentage of contract for sale equal monthly progress payments									90.00%
Long-term accounts receivable	0								$ 0
Proceeds from sale of revenue earned but not billed									6,300	2,800	5,100
Gain (loss) on sale of revenue earned but not billed									$ 100	13	$ 100
Revenue, Practical Expedient, Financing Component [true false]									true
Unbilled accounts receivable	0				500				$ 0	500
Contract assets	1,320				$ 1,966				1,320	$ 1,966
Contract liabilities									500
Voltrek LLC
Disaggregation Of Revenue [Line Items]
Contract assets	$ 500								500
Light fixture sales-type lease
Disaggregation Of Revenue [Line Items]
Revenues									2,800
Sale of tax credits
Disaggregation Of Revenue [Line Items]
Revenues									100
Legacy solar facilities
Disaggregation Of Revenue [Line Items]
Revenues									$ 100