Fair Value (Tables)

3 Months Ended

Mar. 31, 2021

Fair Value Disclosures [Abstract]

Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis

The tables below set forth, by level, our financial assets that are accounted for at fair value for the respective periods. The table does not include assets and liabilities that are measured at historical cost or any basis other than fair value (in thousands):

	Fair Value Measured at Reporting Date Using
March 31, 2021	Level 1		Level 2		Level 3		Total
Assets
Cash equivalents:
Money market funds	$	150,367	$	—	$	—	$	150,367
	$	150,367	$	—	$	—	$	150,367
Liabilities
Derivatives:
Natural gas fixed price forward contracts	$	—	$	1,650	$	—	$	1,650
Embedded EPP derivatives	—		—		6,060		6,060
Interest rate swap agreements	—		11,301		—		11,301
	$	—	$	12,951	$	6,060	$	19,011

	Fair Value Measured at Reporting Date Using
December 31, 2020	Level 1		Level 2		Level 3		Total
Assets
Cash equivalents:
Money market funds	$	235,902	$	—	$	—	$	235,902
	$	235,902	$	—	$	—	$	235,902
Liabilities
Derivatives:
Natural gas fixed price forward contracts	$	—	$	—	$	2,574	$	2,574
Embedded EPP derivatives	—		—		5,541		5,541
Interest rate swap agreements	—		15,989		—		15,989
	$	—	$	15,989	$	8,115	$	24,104

Change in Level 3 Financial Liabilities

The changes in the Level 3 financial liabilities during the three months ended March 31, 2021 were as follows (in thousands):

	Natural Gas Fixed Price Forward Contracts		Embedded EPP Derivative Liability		Total
Liabilities at December 31, 2019	$	6,968	$	6,176	$	13,144
Settlement of natural gas fixed price forward contracts	(4,503)		—		(4,503)
Changes in fair value	109		(635)		(526)
Liabilities at December 31, 2020	2,574		5,541		8,115
Settlement of natural gas fixed price forward contracts	(731)		—		(731)
Changes in fair value	(193)		519		326
Transfer from Level 3 to Level 2 in fair value hierarchy	(1,650)		—		(1,650)
Liabilities at March 31, 2021	$	—	$	6,060	$	6,060

Schedule of Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation

Schedule of Fair Values and Carrying Values of Customer Receivables and Debt Instruments

The following table presents the estimated fair values and carrying values of customer receivables and debt instruments (in thousands):

	March 31, 2021				December 31, 2020
	Net Carrying Value		Fair Value		Net Carrying Value		Fair Value
Customer receivables
Customer financing receivables	$	49,395	$	41,039	$	50,746	$	42,679
Debt instruments
Recourse:
10.25% Senior Secured Notes due March 2027	68,703		70,873		68,614		71,831
2.5% Green Convertible Senior Notes due August 2025	221,387		400,009		99,394		426,229
Non-recourse:
7.5% Term Loan due September 2028	30,869		37,044		31,746		37,658
6.07% Senior Secured Notes due March 2030	76,130		85,830		77,007		89,654
LIBOR + 2.5% Term Loan due December 2021	111,410		113,165		114,138		116,113