Fair Value Measurements (Tables)

9 Months Ended

Sep. 30, 2020

Fair Value Disclosures [Abstract]

Fair value of assets and liabilities that are measured at fair value on a recurring basis

The following table presents the fair value at September 30, 2020 of our assets and liabilities that are measured at fair value on a recurring basis (dollars in thousands):

	Level 1		Level 2		Level 3		Other			Total
Assets
Cash equivalents	$	146,680	$	—	$	—	$	—		$	146,680
Risk management activities — derivative instruments:
Commodity contracts	$	—	$	20,206	$	307	$	(3,209)	(a)	$	17,304
Nuclear decommissioning trust:
Equity securities	24,537		—		—		(14,148)		(b)	10,389
U.S. commingled equity funds	—		—		—		545,845		(c)	545,845
U.S. Treasury debt	153,213		—		—		—			153,213
Corporate debt	—		146,682		—		—			146,682
Mortgage-backed securities	—		101,456		—		—			101,456
Municipal bonds	—		99,192		—		—			99,192
Other fixed income	—		13,060		—		—			13,060
Subtotal nuclear decommissioning trust	177,750		360,390		—		531,697			1,069,837
Other special use funds:
Equity securities	8,090		—		—		1,444		(b)	9,534
U.S. Treasury debt	245,156		—		—		—			245,156
Municipal bonds	—		13,602		—		—			13,602
Subtotal other special use funds	253,246		13,602		—		1,444			268,292
Total assets	$	577,676	$	394,198	$	307	$	529,932		$	1,502,113
Liabilities
Risk management activities — derivative instruments:
Commodity contracts	$	—	$	(10,737)	$	(4,546)	$	1,925	(a)	$	(13,358)

(a)Represents counterparty netting, margin, and collateral. See Note 7.

(b)Represents net pending securities sales and purchases.

(c)Valued using NAV as a practical expedient and, therefore, are not classified in the fair value hierarchy.

The following table presents the fair value at December 31, 2019 of our assets and liabilities that are measured at fair value on a recurring basis (dollars in thousands):

	Level 1		Level 2		Level 3		Other			Total
Assets
Risk management activities — derivative instruments:
Commodity contracts	$	—	$	551	$	33	$	(69)	(a)	$	515
Nuclear decommissioning trust:
Equity securities	10,872		—		—		2,401		(b)	13,273
U.S. commingled equity funds	—		—		—		518,844		(c)	518,844
U.S. Treasury debt	160,607		—		—		—			160,607
Corporate debt	—		115,869		—		—			115,869
Mortgage-backed securities	—		118,795		—		—			118,795
Municipal bonds	—		73,040		—		—			73,040
Other fixed income	—		10,347		—		—			10,347
Subtotal nuclear decommissioning trust	171,479		318,051		—		521,245			1,010,775
Other special use funds:
Equity securities	7,142		—		—		474		(b)	7,616
U.S. Treasury debt	232,848		—		—		—			232,848
Municipal bonds	—		4,631		—		—			4,631
Subtotal other special use funds	239,990		4,631		—		474			245,095
Total assets	$	411,469	$	323,233	$	33	$	521,650		$	1,256,385
Liabilities
Risk management activities — derivative instruments:
Commodity contracts	$	—	$	(67,992)	$	(3,429)	$	(711)	(a)	$	(72,132)

(a)Represents counterparty netting, margin, and collateral. See Note 7.

(b)Represents net pending securities sales and purchases.

(c)Valued using NAV as a practical expedient and, therefore, are not classified in the fair value hierarchy.