Fair Value (Tables)

6 Months Ended

Jun. 30, 2018

Fair Value, Assets and Liabilities Measured on Recurring Basis

The tables below sets forth, by level, the Company’s 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, 2018	Level 1		Level 2		Level 3		Total
Assets
Cash equivalents
Money market funds	$	91,380	$	—	$	—	$	91,380
Short-term investments	15,703		—		—		15,703
Bank loan swap agreements	—		912		—		912
	$	107,083	$	912	$	—	$	107,995
Liabilities
Derivatives
Natural gas fixed price forward contracts	$	—	$	—	$	13,127	$	13,127
Embedded derivative on 6% promissory notes	—		—		176,686		176,686
Bank loan swap agreements	—		2,747		—		2,747
Stock warrants
Preferred stock warrants	—		—		2,369		2,369
	$	—	$	2,747	$	192,182	$	194,929



	Fair Value Measured at Reporting Date Using
December 31, 2017	Level 1		Level 2		Level 3		Total
Assets
Cash equivalents
Money market funds	$	79,256	$	—	$	—	$	79,256
Short-term investments	26,816		—		—		26,816
Bank loan swap agreements	—		52		—		52
	$	106,072	$	52	$	—	$	106,124
Liabilities
Derivatives
Natural gas fixed price forward contracts	$	—	$	—	$	15,368	$	15,368
Embedded derivative on 6% promissory notes	—		—		140,771		140,771
Bank loan swap agreements	—		5,904		—		5,904
Stock warrants
Preferred stock warrants	—		—		9,825		9,825
	$	—	$	5,904	$	165,964	$	171,868

Schedule of Natural Gas Forward Contracts

The following table provides the fair value of the Company’s natural gas fixed price contracts (dollars in thousands):

June 30, 2018

December 31, 2017

Number of

Contracts

(MMBTU)(2)

Fair

Value

Number of

Contracts

(MMBTU)(2)

Fair

Value

Liabilities(1)

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

3,752

13,127

4,332

15,368

(1) Recorded in other current liabilities and derivative liabilities in the consolidated balance sheets.

(2) One MMBTU 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			Derivative Liability		Total

Balances at December 31, 2016	$	18,585		$	12,885		$	115,807	$	147,277
Settlement of natural gas fixed price forward contracts	(4,248		)	—			—		(4,248		)
Embedded derivative on notes	—			—			6,804		6,804
Changes in fair value	1,031			(3,060		)	18,160		16,131
Balances at December 31, 2017	$	15,368		$	9,825		$	140,771	$	165,964
Settlement of natural gas fixed price forward contracts	(2,292		)	—			—		(2,292		)
Embedded derivative on notes	—			—			2,235		2,235
Changes in fair value	51			(7,456		)	7,497		92
Balances at June 30, 2018	$	13,127		$	2,369		$	150,503	$	165,999

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, 2018				December 31, 2017
	Carrying Value		Fair Value		Carrying Value		Fair Value

Customer receivables:
Customer financing receivables	$	75,361	$	52,517	$	77,885	$	55,255
Debt instruments:
5.22% senior secured notes	$	84,191	$	87,275	$	89,564	$	95,114
Term loan due September 2028	36,684		44,599		36,940		46,713
Term loan due October 2020	24,133		26,797		24,364		27,206
6.07% senior secured notes	83,223		88,781		84,032		93,264
Term loan due December 2021	124,526		130,025		125,596		131,817
Term loan due November 2020	4,050		4,265		4,888		5,148
8% & 5% convertible promissory notes	254,120		98,486		244,717		211,000
6% convertible promissory notes and embedded derivatives	290,382		360,565		377,496		359,865
10% notes	95,140		101,953		94,517		106,124