Employee Benefit Plans (Tables)

6 Months Ended

Jun. 30, 2020

Retirement Benefits [Abstract]

Schedule of Components of Expense/(Income) Related to Net Benefit Expense

	Pension Benefits Cost
(Dollars in millions)	Second Quarters				Six Months
	2020		2019		2020		2019
Service Cost Included in Labor and Fringe	$	10	$	8	$	20	$	16
Interest Cost	21		26		41		52
Expected Return on Plan Assets	(44)		(43)		(87)		(86)
Amortization of Net Loss	14		8		28		15
Total Included in Other Income - Net	(9)		(9)		(18)		(19)
Net Periodic Benefit Cost/(Credit)	$	1	$	(1)	$	2	$	(3)
	Other Post-retirement Benefits Cost
(Dollars in millions)	Second Quarters				Six Months
	2020		2019		2020		2019
Service Cost Included in Labor and Fringe	$	1	$	1	$	1	$	1
Interest Cost	—		1		1		2
Amortization of Prior Service Costs	(1)		(1)		(3)		(3)
Total Included in Other Income - Net	(1)		—		(2)		(1)
Net Periodic Benefit Cost/(Credit)	$	—	$	1	$	(1)	$	—