Business Segment Information - Nonoperating Income (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2025	Mar. 31, 2024
Noninterest income:
Fixed income	$ 49	$ 52
Deposit transactions and cash management	40	44
Brokerage, management fees and commissions	26	24
Card and digital banking fees	18	19
Other service charges and fees	12	13
Trust services and investment management	12	11
Mortgage banking income	8	9
Other income	16	22
Total noninterest income	181	194
Underwriting, portfolio advisory, and other noninterest income
Noninterest income:
Revenue from contract with customer	9	10
Commercial, Consumer & Wealth
Noninterest income:
Fixed income	0	0
Deposit transactions and cash management	37	41
Brokerage, management fees and commissions	26	24
Card and digital banking fees	16	17
Other service charges and fees	12	12
Trust services and investment management	12	11
Mortgage banking income	0	0
Other income	7	5
Total noninterest income	110	110
Wholesale
Noninterest income:
Fixed income	49	52
Deposit transactions and cash management	1	1
Brokerage, management fees and commissions	0	0
Card and digital banking fees	0	0
Other service charges and fees	0	0
Trust services and investment management	0	0
Mortgage banking income	8	9
Other income	1	0
Total noninterest income	59	62
Corporate
Noninterest income:
Fixed income	0	0
Deposit transactions and cash management	2	2
Brokerage, management fees and commissions	0	0
Card and digital banking fees	2	2
Other service charges and fees	0	1
Trust services and investment management	0	0
Mortgage banking income	0	0
Other income	8	17
Total noninterest income	$ 12	$ 22