DISPOSED AND DISCONTINUED OPERATIONS - Disposed Operations (Details) - Grid Tied Central Solar Inverter Services Business[Member] - Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member] - Bold Renewables Holdings, LLC [Member] - USD ($)	1 Months Ended	3 Months Ended
	May 31, 2019	Mar. 31, 2020	Dec. 31, 2019
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposed operations of services	$ 1.00
Loan	2,800,000	$ 1,000,000.0	$ 1,500,000
Amount available to borrow	$ 2,750,000
Loan term	10 years
Disposed operation of discount eligibility	30 days
Disposed operations recognized reduction to gain on sale	$ 2,300,000
Non-cash gain, net of tax expense, from discontinued operations	8,600,000
Continuing Operations [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposed operations of extended warranty service obligation	22,000,000.0
Non cash gain from continuing operations	14,800,000
Discontinued Operations [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposed operations of reduced liabilities held in discontinued operations	10,900,000
Tax expense from discontinued operations	$ 2,400,000
Interest Rate, First Seven Years [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposed operations of interest (percent)	0.00%
Interest Rate, Thereafter [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposed operations of interest (percent)	5.00%
Discounts On First Three Years [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposed operations of early payment discounts (percent)	50.00%
Discounts On Year Four And Five [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposed operations of early payment discounts (percent)	45.00%
Discounts Thereafter [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposed operations of early payment discounts (percent)	40.00%