Fair Value (Tables)

12 Months Ended

Dec. 31, 2021

Fair Value Disclosures [Abstract]

Schedule of Carrying Value and Estimated Fair Value of Financial Instruments

The following table sets forth the carrying value and estimated fair value of the Company’s financial instruments not reported at estimated fair value on the Consolidated Balance Sheets as of December 31 (dollars in thousands):

	2021				2020
	Carrying Value		Estimated Fair Value		Carrying Value		Estimated Fair Value
Long-term debt (Level 2)	$	963,500	$	1,157,651	$	963,500	$	1,189,824
Long-term debt (Level 3)		1,200,000		1,366,619		1,060,000		1,235,248
Snettisham finance lease obligation (Level 3)		48,815		54,000		51,750		58,700
Long-term debt to affiliated trusts (Level 3)		51,547		43,299		51,547		43,815

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

The following table discloses by level within the fair value hierarchy the Company’s assets and liabilities measured and reported on the Consolidated Balance Sheets as of December 31, 2021 at fair value on a recurring basis (dollars in thousands):

	Level 1		Level 2		Level 3		Counterparty and Cash Collateral Netting (1)			Total
December 31, 2021
Assets:
Energy commodity derivatives	$	—	$	34,119	$	—	$	(31,211	)	$	2,908
Level 3 energy commodity derivatives:
Natural gas exchange agreements		—		—		143		(143	)		—
Interest rate swap derivatives		—		2,319		—		(1,170	)		1,149
Deferred compensation assets:
Mutual Funds:
Fixed income securities (2)		1,809		—		—		—			1,809
Equity securities (2)		7,594		—		—		—			7,594
Total	$	9,403	$	36,438	$	143	$	(32,524	)	$	13,460
Liabilities:
Energy commodity derivatives	$	—	$	41,733	$	—	$	(40,300	)	$	1,433
Level 3 energy commodity derivatives:
Natural gas exchange agreement		—		—		7,914		(143	)		7,771
Foreign currency exchange derivatives		—		19		—		—			19
Interest rate swap derivatives		—		25,274		—		(1,170	)		24,104
Total	$	—	$	67,026	$	7,914	$	(41,613	)	$	33,327

The following table discloses by level within the fair value hierarchy the Company’s assets and liabilities measured and reported on the Consolidated Balance Sheets as of December 31, 2020 at fair value on a recurring basis (dollars in thousands):

	Level 1		Level 2		Level 3		Counterparty and Cash Collateral Netting (1)			Total
December 31, 2020
Assets:
Energy commodity derivatives	$	—	$	23,645	$	—	$	(22,152	)	$	1,493
Level 3 energy commodity derivatives:
Natural gas exchange agreement		—		—		75		(75	)		—
Foreign currency exchange derivatives		—		30		—		—			30
Interest rate swap derivatives		—		952		—		(952	)		—
Deferred compensation assets:
Mutual Funds:
Fixed income securities (2)		2,471		—		—		—			2,471
Equity securities (2)		6,228		—		—		—			6,228
Total	$	8,699	$	24,627	$	75	$	(23,179	)	$	10,222
Liabilities:
Energy commodity derivatives	$	—	$	23,030	$	—	$	(22,768	)	$	262
Level 3 energy commodity derivatives:
Natural gas exchange agreement		—		—		8,485		(75	)		8,410
Interest rate swap derivatives		—		51,765		—		(9,002	)		42,763
Total	$	—	$	74,795	$	8,485	$	(31,845	)	$	51,435

(1)The Company is permitted to net derivative assets and derivative liabilities with the same counterparty when a legally enforceable master netting agreement exists. In addition, the Company nets derivative assets and derivative liabilities against any payables and receivables for cash collateral held or placed with these same counterparties.

(2)These assets are included in other property and investments-net and other non-current assets on the Consolidated Balance Sheets.

Schedule of Quantitative Information

The following table presents the quantitative information which was used to estimate the fair values of the Level 3 assets and liabilities above as of December 31, 2021 (dollars in thousands):

	Fair Value (Net) at
	December 31, 2021			Valuation Technique	Unobservable Input	Range
Natural gas exchange		(7,771	)	Internally derived weighted average cost of gas	Forward purchase prices	$2.35 - $4.08/mmBTU $2.96 Weighted Average
					Forward sales prices	$2.38 - $9.50/mmBTU $4.51 Weighted Average
					Purchase volumes	130,000 - 310,000 mmBTUs
					Sales volumes	25,000 - 310,000 mmBTUs

Schedule of Activity For Energy Commodity Derivative Assets (Liabilities) Measured At Fair Value Using Significant Unobservable Inputs (Level 3)

The following table presents activity for energy commodity derivative assets (liabilities) measured at fair value using significant unobservable inputs (Level 3) for the years ended December 31 (dollars in thousands):

	Natural Gas Exchange Agreement			Power Exchange Agreement			Total
Year ended December 31, 2021:
Balance as of January 1, 2021	$	(8,410	)	$	—		$	(8,410	)
Total gains or (losses) (realized/unrealized):
Included in regulatory assets (1)		4,292			—			4,292
Settlements		(3,653	)		—			(3,653	)
Ending balance as of December 31, 2021 (2)	$	(7,771	)	$	—		$	(7,771	)
Year ended December 31, 2020:
Balance as of January 1, 2020	$	(2,976	)	$	—		$	(2,976	)
Total gains or (losses) (realized/unrealized):
Included in regulatory assets (1)		(4,311	)		—			(4,311	)
Settlements		(1,123	)		—			(1,123	)
Ending balance as of December 31, 2020 (2)	$	(8,410	)	$	—		$	(8,410	)
Year ended December 31, 2019:
Balance as of January 1, 2019	$	(2,774	)	$	(2,488	)	$	(5,262	)
Total gains or (losses) (realized/unrealized):
Included in regulatory assets (1)		8,175			435			8,610
Settlements		(8,377	)		2,053			(6,324	)
Ending balance as of December 31, 2019 (2)	$	(2,976	)	$	—		$	(2,976	)

(1)All gains and losses are included in other regulatory assets and liabilities. There were no gains and losses included in either net income or other comprehensive income during any of the periods presented in the table above.

(2)There were no purchases, issuances or transfers from other categories of any derivatives instruments during the periods presented in the table above.

Schedule of Nonrecurring Fair Value Measurements

Nonrecurring Fair Value Measurements

The Company holds equity investments without a readily determinable fair value, and these assets are recorded at fair value and adjusted on a nonrecurring basis as a result of observable changes in fair value using the measurement alternative. Amounts recognized in the consolidated financial statements related to equity investments without readily determinable fair value include the following (dollars in thousands):

	December 31, 2021		December 31, 2020
Carrying Value (1)	$	24,161	$	15,110
Gains (losses)		8,761		925

(1)Carrying value is adjusted to fair value as of the measurement date when observable changes in fair value occur, such as a transaction involving the underlying asset. These assets are measured using a market approach and are level 2 assets.