Fair Value Measurements (Tables)

9 Months Ended

Sep. 30, 2021

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, 2021 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	$	—	$	197,874	$	9	$	(2,606)	(a)	$	195,277
Nuclear decommissioning trust:
Equity securities	33,794		—		—		(23,543)		(b)	10,251
U.S. commingled equity funds	—		—		—		705,946		(c)	705,946
U.S. Treasury debt	183,084		—		—		—			183,084
Corporate debt	—		141,744		—		—			141,744
Mortgage-backed securities	—		115,714		—		—			115,714
Municipal bonds	—		60,188		—		—			60,188
Other fixed income	—		8,558		—		—			8,558
Subtotal nuclear decommissioning trust	216,878		326,204		—		682,403			1,225,485
Other special use funds:
Equity securities	25,071		—		—		1,392		(b)	26,463
U.S. Treasury debt	336,494		—		—		—			336,494
Municipal bonds			11,886		—		—			11,886
Subtotal other special use funds	361,565		11,886		—		1,392			374,843
Total assets	$	578,443	$	535,964	$	9	$	681,189		$	1,795,605
Liabilities
Risk management activities — derivative instruments:
Commodity contracts	$	—	$	(2,674)	$	(26)	$	1,048	(a)	$	(1,652)

(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, 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
Risk management activities — derivative instruments:
Commodity contracts	$	—	$	9,016	$	4	$	(4,271)	(a)	$	4,749
Nuclear decommissioning trust:
Equity securities	29,796		—		—		(17,828)		(b)	11,968
U.S. commingled equity funds	—		—		—		610,055		(c)	610,055
U.S. Treasury debt	164,514		—		—		—			164,514
Corporate debt	—		149,509		—		—			149,509
Mortgage-backed securities	—		99,623		—		—			99,623
Municipal bonds	—		89,705		—		—			89,705
Other fixed income	—		13,061		—		—			13,061
Subtotal nuclear decommissioning trust	194,310		351,898		—		592,227			1,138,435
Other special use funds:
Equity securities	37,337		—		—		504		(b)	37,841
U.S. Treasury debt	203,220		—		—		—			203,220
Municipal bonds	—		13,448		—		—			13,448
Subtotal other special use funds	240,557		13,448		—		504			254,509
Total assets	$	434,867	$	374,362	$	4	$	588,460		$	1,397,693
Liabilities
Risk management activities — derivative instruments:
Commodity contracts	$	—	$	(20,498)	$	(1,107)	$	2,986	(a)	$	(18,619)

(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.