FAIR VALUE MEASUREMENTS (Tables)

12 Months Ended

Dec. 31, 2019

Fair Value Disclosures [Abstract]

Schedule of Assets and Liabilities Measured at Fair Value on a Recurring Basis

The following table presents the Company’s liabilities that were measured at fair value on a recurring basis and its categorization within the fair value hierarchy.

	Fair Value Hierarchy	December 31, 2019		December 31, 2018
		(In thousands)
Warranty obligations
Current		$	6,794	$	4,288
Non-current		13,012		7,469
Total warranty obligations measured at fair value	Level 3	$	19,806	$	11,757

Schedule of Changes in Nonfinancial Liabilities Related to Warrant Obligations Measured at Fair Value on a Recurring Basis Using Significant Unobservable Inputs

The following table provides information regarding changes in nonfinancial liabilities related to the Company’s warranty obligations measured at fair value on a recurring basis using significant unobservable inputs (Level 3) for the periods indicated.

	Years Ended December 31,
	2019			2018			2017
	(In thousands)
Balance at beginning of period	$	11,757		$	9,791		$	10,332
Accruals for warranties issued during period	5,244			3,040			3,591
Changes in estimates	6,167			2,455			(4,551		)
Settlements	(6,212		)	(4,030		)	(1,956		)
Increase due to accretion expense	2,326			1,989			2,053
Other	524			(1,488		)	322
Balance at end of period	$	19,806		$	11,757		$	9,791

Summary of Significant Unobservable Inputs used in the Fair Value Measurement of Liabilities Designated as Level 3

As of December 31, 2019 and December 31, 2018, the significant unobservable inputs used in the fair value measurement of the Company’s liabilities designated as Level 3 are as follows:

			Percent Used (Weighted Average)
Item Measured at Fair Value	Valuation Technique	Description of Significant Unobservable Input	December 31, 2019	December 31, 2018
Warranty obligations for microinverters sold since January 1, 2014	Discounted cash flows	Profit element and risk premium	14%	16%
		Credit-adjusted risk-free rate	16%	19%