ACQUISITION - Summary of Consideration Transferred for Business Acquisition (Details) - USD ($) $ in Thousands		12 Months Ended
	Aug. 09, 2018	Dec. 31, 2018
Business Acquisition [Line Items]
Cash consideration	$ 25,000
Common stock issued	32,319
Total	57,319
SunPower’s
Business Acquisition [Line Items]
Cash consideration	25,000	$ 15,000
Common stock issued	32,319
Total	57,319
Developed technology and goodwill
Business Acquisition [Line Items]
Cash consideration	15,000
Common stock issued	19,219
Total	34,219
Customer relationship
Business Acquisition [Line Items]
Cash consideration	10,000
Common stock issued	13,100
Total	$ 23,100