Employee Retirement Benefits (Tables)

9 Months Ended

Sep. 30, 2021

Retirement Benefits [Abstract]

Schedule of Defined Benefit Plans Disclosures

The following summarizes the components of net periodic benefit cost for our qualified and supplemental pension plans:

(Dollars in millions)	Three months ended September 30,				Nine months ended September 30,
	2021		2020		2021		2020
Service cost	$	2	$	2	$	7	$	7
Non-service costs (benefit):
Interest cost	2		3		7		9
Expected return on plan assets	(5)		(5)		(16)		(16)
Amortization of actuarial loss and prior service cost	2		—		5		2
Other	—		—		2		—
Total non-service benefit	(1)		(2)		(2)		(5)
Net periodic benefit cost	$	1	$	—	$	5	$	2