Income Taxes (Tables)

12 Months Ended

Dec. 31, 2022

Income Tax Disclosure [Abstract]

Details of Income Tax Expense for Continuing Operations Including Noncontrolling Interests

Year Ended December 31,	2022			2021			2020
(millions)
Current:
Federal	$	(69	)	$	(52	)	$	(139	)
State		(3	)		(39	)		3
Total current benefit		(72	)		(91	)		(136	)
Deferred:
Federal
Taxes before operating loss carryforwards and investment tax credits		135			61			158
Tax utilization expense of operating loss carryforwards		33			34			33
State		36			7			17
Total deferred expense		204			102			208
Investment tax credit-amortization		(1	)		(2	)		(1	)
Total income tax expense	$	131		$	9		$	71

Schedule of Effective Income Tax Rate Reconciliation

Year Ended December 31,	2022			2021			2020
U.S. statutory rate		21.0	%		21.0	%		21.0	%
Increases (reductions) resulting from:
State taxes, net of federal benefit		4.7			5.6			4.2
AFUDC - equity		—			(0.4	)		(0.1	)
Amortization of federal investment tax credits		(0.2	)		(0.6	)		(0.4	)
Reversal of excess deferred income taxes		(4.6	)		(8.1	)		(6.0	)
Changes in unrecognized tax benefits		—			(15.8	)		—
Prior period adjustments		—			1.6			—
Other		(0.2	)		0.5			0.1
Effective tax rate		20.7	%		3.8	%		18.8	%

Schedule of Deferred Income Taxes

DESC’s deferred income taxes consist of the following:

At December 31,	2022			2021
(millions)
Deferred income taxes:
Total deferred income tax assets	$	892		$	1,015
Total deferred income tax liabilities		2,107			1,974
Total net deferred income tax liabilities	$	1,215		$	959
Total deferred income taxes:
Depreciation method and plant basis differences	$	1,164		$	1,139
Excess deferred income taxes		(219	)		(228	)
Unrecovered nuclear plant cost		479			508
DESC rate refund		(89	)		(113	)
Toshiba settlement		(162	)		(189	)
Nuclear decommissioning		(44	)		(54	)
Deferred state income taxes		275			226
Federal benefit of deferred state income taxes		(60	)		(47	)
Deferred fuel, purchased energy and gas costs		107			27
Pension benefits		51			35
Other postretirement benefits		(32	)		(35	)
Loss and credit carryforwards		(313	)		(343	)
Other		58			33
Total net deferred income tax liabilities	$	1,215		$	959
Deferred investment tax credits-regulated operations		15			16
Total deferred taxes and deferred investment tax credits	$	1,230		$	975

Summary of Tax Credit Carryforwards

At December 31, 2022, DESC had the following deductible loss and credit carryforwards:

(millions)	Deductible Amount		Deferred Tax Asset		Expiration Period
Federal losses	$	731	$	153	2037
Federal production and other credits		—		29	2035-2042
State losses		2,779		139	2037-2042
State investment and other credits		—		32	2026-2032
Total	$	3,510	$	353

Schedule of Unrecognized Tax Benefits Roll Forward

A reconciliation of changes in DESC’s unrecognized tax benefits follows:

(millions)	2022			2021			2020
Beginning balance	$	62		$	138		$	132
Increases-prior period positions		6			6			5
Decreases-prior period positions		(1	)		(57	)		—
Increases-current period positions		1			1			1
Settlements with tax authorities		—			(26	)		—
Ending balance	$	68		$	62		$	138