Income Taxes (Tables)

12 Months Ended

Dec. 31, 2020

Income Tax Disclosure [Abstract]

Components of income tax expense (benefit)

	Years Ended December 31,
	2020		2019	2018
	(Dollars in millions)
Income tax expense was as follows:
Federal
Current	$	—	12	—
Deferred	162		186	199
State and local
Current	22		4	(9)
Deferred	42		41	28
Foreign
Current	19		17	30
Deferred	(24)		(5)	(52)
Total income tax expense	$	221	255	196

Schedule of income before income tax, domestic and foreign

	Years Ended December 31,
	2020		2019	2018
	(Dollars in millions)
Income tax expense was allocated as follows:
Income tax expense in the consolidated statements of operations:
Attributable to income	$	221	255	196
Member's equity:
Tax effect of the change in accumulated other comprehensive loss	$	43	5	(49)

Schedule of effective income tax rate reconciliation

The following is a reconciliation from the statutory federal income tax rate to our effective income tax rate:

	Years Ended December 31,
	2020		2019		2018
	(Percentage of pre-tax income)
Statutory federal income tax rate	21.0	%	21.0	%	21.0	%
State income taxes, net of federal income tax benefit	5.8	%	(1.2)	%	2.8	%
Goodwill impairment	—	%	(26.4)	%	—	%
Tax law changes	(1.5)	%	(0.2)	%	17.2	%
Global intangible low-taxed income	—	%	(0.4)	%	1.8	%
Net foreign income tax	0.9	%	(0.8)	%	(4.8)	%
Executive compensation limitation	—	%	(0.2)	%	1.2	%
Research and development credits	(0.6)	%	0.1	%	(1.3)	%
Other, net	(0.3)	%	(0.5)	%	(1.4)	%
Effective income tax rate	25.3	%	(8.6)	%	36.5	%

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,
	2020		2019
	(Dollars in millions)
Deferred tax assets
Deferred revenue	$	277	306
Net operating loss carry forwards	3,503		3,233
Property, plant and equipment	65		58
Other	343		326
Gross deferred tax assets	4,188		3,923
Less valuation allowance	(1,170)		(892)
Net deferred tax assets	3,018		3,031
Deferred tax liabilities
Deferred revenue	(34)		(41)
Property, plant and equipment	(1,264)		(974)
Intangible assets	(1,773)		(1,898)
Other	(33)		(29)
Gross deferred tax liabilities	(3,104)		(2,942)
Net deferred tax (liabilities) assets	$	(86)	89

Schedule 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 2020 and 2019 is as follows:

	2020		2019
	(Dollars in millions)
Unrecognized tax benefits at beginning of period	$	952	970
Tax positions of prior periods netted against deferred tax assets	(32)		(24)
Increase in tax positions taken in the prior period	—		1
Increase in tax positions taken in the current period	4		5
Decrease due to settlement/payments	(1)		—
Decrease from the lapse of statute of limitations	—		—
Unrecognized tax benefits at end of period	$	923	952