Income Taxes (Tables)

12 Months Ended

Dec. 31, 2023

Income Tax Disclosure [Abstract]

Schedule of components of the income tax expense from continuing operations

The components of the income tax expense from continuing operations are as follows:

	Years Ended December 31,
	2023		2022	2021
	(Dollars in millions)
Income tax expense:
Federal and foreign
Current	$	432	514	553
Deferred	19		6	17
State and local
Current	107		137	129
Deferred	3		14	10
Income tax expense	$	561	671	709

Schedule of effective income tax rate for continuing operations that differs from the statutory tax rate

The effective income tax rate for continuing operations differs from the statutory tax rate as follows:

	Years Ended December 31,
	2023		2022		2021
	(in percent)
Effective income tax rate:
Federal statutory income tax rate	21.0	%	21.0	%	21.0	%
State income taxes-net of federal effect	(31.3)	%	4.3	%	3.7	%
Goodwill impairment	(187.2)	%	—	%	—	%
Change in liability for unrecognized tax position	(8.9)	%	0.6	%	0.4	%
Other	(1.4)	%	—	%	0.1	%
Effective income tax rate	(207.8)	%	25.9	%	25.2	%

For the years ended December 31, 2023 and 2022, our effective income tax rate was (207.8)% and 25.9%, respectively. The effective tax rate for the year ended December 31, 2023 includes a $505 million unfavorable aggregate impact of non-deductible goodwill impairment.

Schedule of components of the deferred tax assets and liabilities

The tax effects of temporary differences that gave rise to significant portions of the deferred tax assets and deferred tax liabilities were as follows:

	As of December 31,
	2023		2022
	(Dollars in millions)
Deferred tax liabilities:
Property, plant and equipment	$	(1,464)	(1,414)
Intangible assets	(95)		(114)
Other	(50)		(54)
Total deferred tax liabilities	(1,609)		(1,582)
Deferred tax assets:
Payable to affiliate due to post-retirement benefit plan participation	292		302
Gross deferred tax assets	292		302
Less valuation allowance on deferred tax assets	—		—
Net deferred tax assets	292		302
Net deferred tax liabilities	$	(1,317)	(1,280)

Reconciliation of unrecognized tax benefits

A reconciliation of the change in our gross unrecognized tax benefits (excluding both interest and any related federal benefit) from January 1 to December 31 for 2023 and 2022 are as follows:

	Years ended December 31,
	2023		2022
	(Dollars in millions)
Unrecognized tax benefits at beginning of period	$	332	360
Decrease due to tax positions taken in a prior year	(1)		(28)
Decrease due to tax positions taken in a current year	(14)		—
Unrecognized tax benefits at end of period	$	317	332