Employee Pension and Other Postretirement Benefits (Tables)

6 Months Ended

Jun. 30, 2021

Retirement Benefits [Abstract]

Components of Net Periodic Benefit Cost

The following tables summarize the components of net periodic benefit cost for the three and six months ended June 30, 2021 and 2020. The components of net periodic benefit cost other than the service cost component are included in other noninterest expense in the income statement.

	Pension Benefits				Other Postretirement Benefits				Superannuation, SERP and ESBP
	For the Three Months Ended June 30,				For the Three Months Ended June 30,				For the Three Months Ended June 30,
(Dollars in millions)	2021		2020		2021		2020		2021		2020
Components of net periodic benefit cost:
Service cost	$	22	$	22	$	1	$	1	$	—	$	—
Interest cost	17		24		1		1		—		1
Expected return on plan assets	(69)		(66)		(6)		(5)		—		—
Amortization of prior service credit	(6)		(7)		—		—		—		—
Recognized net actuarial loss	30		26		—		—		1		—
Total net periodic benefit (income) cost	$	(6)	$	(1)	$	(4)	$	(3)	$	1	$	1

	Pension Benefits				Other Postretirement Benefits				Superannuation, SERP and ESBP
	For the Six Months Ended June 30,				For the Six Months Ended June 30,				For the Six Months Ended June 30,
(Dollars in millions)	2021		2020		2021		2020		2021		2020
Components of net periodic benefit cost:
Service cost	$	46	$	43	$	1	$	1	$	—	$	—
Interest cost	34		48		2		3		1		1
Expected return on plan assets	(138)		(133)		(11)		(10)		—		—
Amortization of prior service credit	(13)		(14)		—		—		—		—
Recognized net actuarial loss	60		54		—		—		2		2
Total net periodic benefit (income) cost	$	(11)	$	(2)	$	(8)	$	(6)	$	3	$	3