Fair Value (Tables)

6 Months Ended

Jun. 30, 2019

Fair Value, Assets and Liabilities Measured on Recurring Basis

The tables below sets forth, by level, our financial assets that were 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
June 30, 2019	Level 1		Level 2		Level 3		Total
Assets
Cash equivalents:
Money market funds	$	202,795	$	—	$	—	$	202,795
Interest rate swap agreements	—		12		—		12
	$	202,795	$	12	$	—	$	202,807
Liabilities
Accrued other current liabilities	$	1,636	$	—	$	—	$	1,636
Derivatives:
Natural gas fixed price forward contracts	—		—		8,769		8,769
Interest rate swap agreements¹	—		9,158		—		9,158
	$	1,636	$	9,158	$	8,769	$	19,563

¹As of June 30, 2019, $0.6 million of the gain on the interest rate swaps accumulated in other comprehensive income (loss) is expected to be reclassified into earnings in the next twelve months.



	Fair Value Measured at Reporting Date Using
December 31, 2018	Level 1		Level 2		Level 3		Total
Assets
Cash equivalents:
Money market funds	$	143,843	$	—	$	—	$	143,843
Short-term investments	104,350		—		—		104,350
Interest rate swap agreements	—		82		—		82
	$	248,193	$	82	$	—	$	248,275
Liabilities
Accrued other current liabilities	$	1,331	$	—	$	—	$	1,331
Derivatives:
Natural gas fixed price forward contracts	—		—		9,729		9,729
Interest rate swap agreements	—		3,630		—		3,630
	$	1,331	$	3,630	$	9,729	$	14,690

Schedule of Natural Gas Forward Contracts

The following table provides the fair value of our natural gas fixed price forward contracts (dollars in thousands):

June 30, 2019

December 31, 2018

Number of

Contracts

(MMBTU)²

Fair

Value

Number of
Contracts
(MMBTU)²

Fair

Value

Liabilities¹

Natural gas fixed price forward contracts (not under hedging relationships)

2,581

8,769

3,096

9,729

¹ Recorded in current liabilities and derivative liabilities in the condensed consolidated balance sheets.

² One MMBTU, or one million British Thermal Units, is a traditional unit of energy used to describe the heat value (energy content) of fuels.

Change in Level 3 Financial Liabilities

The changes in the Level 3 financial assets were as follows (in thousands):



	Natural Gas Fixed Price Forward Contracts			Preferred Stock Warrants		Embedded Derivative Liability		Total
Balances at December 31, 2018	$	9,729		$	—	$	—	$	9,729
Settlement of natural gas fixed price forward contracts	(1,610		)	—		—		(1,610		)
Changes in fair value	650			—		—		650
Balances at June 30, 2019	$	8,769		$	—	$	—	$	8,769



	Natural Gas Fixed Price Forward Contracts			Preferred Stock Warrants			Embedded Derivative Liability		Total
Balances at December 31, 2017	$	15,368		$	9,825		$	140,771	$	165,964
Settlement of natural gas fixed price forward contracts	(1,102		)	—			—		(1,102		)
Changes in fair value	855			(3,271		)	9,732		7,316
Balances at June 30, 2018	$	15,121		$	6,554		$	150,503	$	172,178

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):



	June 30, 2019				December 31, 2018
	Net Carrying Value		Fair Value		Net Carrying Value		Fair Value

Customer receivables:
Customer financing receivables	$	69,963	$	52,517	$	72,676	$	51,541
Debt instruments:
Recourse
LIBOR + 4% term loan due November 2020	2,376		2,458		3,214		3,311
5% convertible promissory note due December 2020	35,576		33,524		34,706		31,546
6% convertible promissory notes due December 2020	271,503		393,395		263,284		353,368
10% notes due July 2024	96,384		96,859		95,555		99,260
Non-recourse
5.22% senior secured notes due March 2025	—		—		78,566		80,838
7.5% term loan due September 2028	35,532		41,368		36,319		39,892
LIBOR + 5.25% term loan due October 2020	23,661		25,028		23,916		25,441
6.07% senior secured notes due March 2030	81,223		90,136		82,337		85,917
LIBOR + 2.5% term loan due December 2021	121,952		123,046		123,384		123,040