Employee Benefit Plans (Tables)

12 Months Ended

Dec. 31, 2023

Defined Benefit Plans and Other Postretirement Benefit Plans Disclosures [Abstract]

Schedule of Defined Benefit Plans Disclosures

The following table sets forth reconciliations of plan assets and the projected benefit obligation, the weighted-average assumptions used to determine year-end benefit obligations, and the amounts recognized in accumulated other comprehensive loss for the Corporation’s defined benefit pension plans and postretirement benefit plan at December 31, 2023 and 2022. The Corporation used a measurement date of December 31, 2023 for these plans.

	Defined Benefit Pension Plans
	Qualified						Non-Qualified						Postretirement Benefit Plan
(dollar amounts in millions)	2023			2022			2023			2022			2023			2022
Change in fair value of plan assets:
Fair value of plan assets at January 1	$	2,508		$	3,462		$	—		$	—		$	46		$	53
Actual return on plan assets	338			(777)			—			—			1			(4)
Benefits paid	(165)			(177)			—			—			(2)			(3)
Fair value of plan assets at December 31	$	2,681		$	2,508		$	—		$	—		$	45		$	46
Change in projected benefit obligation:
Projected benefit obligation at January 1	$	1,611		$	2,214		$	163		$	207		$	21		$	31
Service cost	31			37			2			2			—			—
Interest cost	85			62			9			6			1			1
Actuarial gain (loss)	67			(525)			10			(37)			(3)			(8)
Benefits paid	(165)			(177)			(15)			(15)			(2)			(3)
Projected benefit obligation at December 31	$	1,629		$	1,611		$	169		$	163		$	17		$	21
Accumulated benefit obligation	$	1,611		$	1,598		$	166		$	161		$	17		$	21
Funded status at December 31 (a) (b)	$	1,052		$	897		$	(169)		$	(163)		$	28		$	25
Weighted-average assumptions used:
Discount rate	5.33		%	5.60		%	5.33		%	5.60		%	5.43		%	5.71		%
Rate of compensation increase	4.50			4.25			4.50			4.25			n/a			n/a
Interest crediting rate	4.66 - 5.25			3.99 - 5.25			4.66 - 5.25			3.99 - 5.25			n/a			n/a
Amounts recognized in accumulated other comprehensive loss before income taxes:
Net actuarial loss	$	(501)		$	(638)		$	(52)		$	(46)		$	(9)		$	(10)
Prior service credit	19			33			29			38			2			2
Balance at December 31	$	(482)		$	(605)		$	(23)		$	(8)		$	(7)		$	(8)

(a)Based on projected benefit obligation for defined benefit pension plans and accumulated benefit obligation for postretirement benefit plan.

(b)The Corporation recognizes the overfunded and underfunded status of the plans in accrued income and other assets and accrued expenses and other liabilities, respectively, on the Consolidated Balance Sheets.

n/a - not applicable

Changes in Plan Assets and Benefit Obligations Recognized in Other Comprehensive Income (Loss)

The following table details the changes in plan assets and benefit obligations recognized in other comprehensive income (loss) for the year ended December 31, 2023.

	Defined Benefit Pension Plans
(in millions)	Qualified		Non-Qualified		Postretirement Benefit Plan		Total
Actuarial gain (loss) arising during the period	$	105	$	(10)	$	1	$	96
Amortization of net actuarial loss	32		4		—		36
Amortization of prior service credit	(14)		(9)		—		(23)
Total recognized in other comprehensive income (loss)	$	123	$	(15)	$	1	$	109

Components of Net Periodic Defined Benefit Cost

Components of net periodic defined benefit (credit) cost and postretirement benefit credit, the actual return on plan assets and the weighted-average assumptions used were as follows:

	Defined Benefit Pension Plans
(dollar amounts in millions)	Qualified									Non-Qualified
Years Ended December 31	2023			2022			2021			2023			2022			2021
Service cost (a)	$	31		$	37		$	38		$	2		$	2		$	2
Other components of net benefit (credit) cost:
Interest cost	85			62			61			9			6			7
Expected return on plan assets	(166)			(201)			(202)			—			—			—
Amortization of prior service credit	(14)			(14)			(19)			(9)			(9)			(6)
Amortization of actuarial net loss	32			19			29			4			9			11
Total other components of net benefit (credit) cost (b)	(63)			(134)			(131)			4			6			12
Net periodic defined benefit (credit) cost	$	(32)		$	(97)		$	(93)		$	6		$	8		$	14
Actual return on plan assets	$	338		$	(777)		$	291		n/a			n/a			n/a
Actual rate of return on plan assets	13.91		%	(23.02)		%	8.92		%	n/a			n/a			n/a
Weighted-average assumptions used:
Discount rate	5.60		%	2.96		%	2.71		%	5.60		%	2.96		%	2.71		%
Expected long-term return on plan assets	6.50			6.50			6.50			n/a			n/a			n/a
Rate of compensation increase	4.25			4.00			4.00			4.25			4.00			4.00

(a)Included in salaries and benefits expense on the Consolidated Statements of Income.

(b)Included in other noninterest expenses on the Consolidated Statements of Income.

n/a - not applicable

(dollar amounts in millions)	Postretirement Benefit Plan
Years Ended December 31	2023			2022			2021
Other components of net benefit credit:
Interest cost	$	1		$	1		$	1
Expected return on plan assets	(2)			(3)			(3)
Net periodic postretirement benefit credit	$	(1)		$	(2)		$	(2)
Actual return on plan assets	$	1		$	(4)		$	(1)
Actual rate of return on plan assets	2.61		%	(8.24)		%	(2.25)		%
Weighted-average assumptions used:
Discount rate	5.71		%	2.79		%	2.43		%
Expected long-term return on plan assets	5.00			5.00			5.00
Healthcare cost trend rate (a):
Cost trend rate assumed	n/a			n/a			6.00
Rate to which the cost trend rate is assumed to decline (the ultimate trend rate)	n/a			n/a			4.50
Year that the rate reaches the ultimate trend rate	n/a			n/a			2027

Fair Value of Defined Benefit Plan Investments

The fair values of the Corporation’s qualified defined benefit pension plan investments measured at fair value on a recurring basis at December 31, 2023 and 2022, by asset category and level within the fair value hierarchy, are detailed in the table below.

(in millions)	Total		Level 1		Level 2		Level 3
December 31, 2023
Fixed income securities:
U.S. Treasury and other U.S. government agency securities	$	567	$	564	$	3	$	—
Corporate and municipal bonds and notes	786		—		786		—
Private placements	44		—		—		44
Total investments in the fair value hierarchy	$	1,397	$	564	$	789	$	44
Investments measured at net asset value:
Collective investment funds	1,268
Total investments at fair value	$	2,665
December 31, 2022
Fixed income securities:
U.S. Treasury and other U.S. government agency securities	$	534	$	531	$	3	$	—
Corporate and municipal bonds and notes	676		—		676		—
Mortgage-backed securities	20		—		20		—
Private placements	39		—		—		39
Total investments in the fair value hierarchy	$	1,269	$	531	$	699	$	39
Investments measured at net asset value:
Collective investment funds	1,230
Total investments at fair value	$	2,499

Changes in Level 3 Defined Benefit Plan Investments

The table below provides a summary of changes in the Corporation’s qualified defined benefit pension plan’s Level 3 investments measured at fair value on a recurring basis for the years ended December 31, 2023 and 2022.

	Balance at Beginning of Period										Balance at End of Period
			Net Gains (Losses)
(in millions)			Realized		Unrealized		Purchases		Sales
Year Ended December 31, 2023
Private placements	$	39	$	(3)	$	8	$	46	$	(46)	$	44
Year Ended December 31, 2022
Private placements	$	50	$	(3)	$	(12)	$	38	$	(34)	$	39

Estimated Future Benefit Payments

The Corporation currently expects to make no employer contributions to the qualified and non-qualified defined benefit pension plans and postretirement benefit plan for the year ended December 31, 2024.

	Estimated Future Benefit Payments
(in millions) Years Ended December 31	Qualified Defined Benefit Pension Plan		Non-Qualified Defined Benefit Pension Plan		Postretirement Benefit Plan (a)
2024	$	162	$	15	$	3
2025	140		15		2
2026	144		15		2
2027	142		15		2
2028	143		15		2
2029 - 2033	668		73		6

(a)Estimated benefit payments in the postretirement benefit plan are net of estimated Medicare subsidies.