Revenue From Contracts With Customers (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Segment Reporting, Revenue Reconciling Item
Total revenue from contracts with customers	$ 201	$ 198	$ 606	$ 596
Other sources of noninterest income	94	80	274	194
Total noninterest income	295	278	880	790
Commercial Bank
Segment Reporting, Revenue Reconciling Item
Total revenue from contracts with customers	98	97	293	292
Other sources of noninterest income	52	72	167	169
Total noninterest income	150	169	460	461
Retail Bank
Segment Reporting, Revenue Reconciling Item
Total revenue from contracts with customers	30	28	85	87
Other sources of noninterest income	1	1	4	2
Total noninterest income	31	29	89	89
Wealth Management
Segment Reporting, Revenue Reconciling Item
Total revenue from contracts with customers	75	73	229	217
Other sources of noninterest income	3	4	4	9
Total noninterest income	78	77	233	226
Finance & Other
Segment Reporting, Revenue Reconciling Item
Total revenue from contracts with customers	(2)	0	(1)	0
Other sources of noninterest income	38	3	99	14
Total noninterest income	36	3	98	14
Card fees
Segment Reporting, Revenue Reconciling Item
Total revenue from contracts with customers	71	67	212	205
Card fees \| Commercial Bank
Segment Reporting, Revenue Reconciling Item
Total revenue from contracts with customers	58	56	175	171
Card fees \| Retail Bank
Segment Reporting, Revenue Reconciling Item
Total revenue from contracts with customers	12	10	34	31
Card fees \| Wealth Management
Segment Reporting, Revenue Reconciling Item
Total revenue from contracts with customers	1	1	3	3
Card fees \| Finance & Other
Segment Reporting, Revenue Reconciling Item
Total revenue from contracts with customers	0	0	0	0
Fiduciary income
Segment Reporting, Revenue Reconciling Item
Total revenue from contracts with customers	59	58	179	178
Fiduciary income \| Commercial Bank
Segment Reporting, Revenue Reconciling Item
Total revenue from contracts with customers	1	0	1	0
Fiduciary income \| Retail Bank
Segment Reporting, Revenue Reconciling Item
Total revenue from contracts with customers	0	0	0	0
Fiduciary income \| Wealth Management
Segment Reporting, Revenue Reconciling Item
Total revenue from contracts with customers	58	58	178	178
Fiduciary income \| Finance & Other
Segment Reporting, Revenue Reconciling Item
Total revenue from contracts with customers	0	0	0	0
Service charges on deposit accounts
Segment Reporting, Revenue Reconciling Item
Total revenue from contracts with customers	47	50	140	148
Service charges on deposit accounts \| Commercial Bank
Segment Reporting, Revenue Reconciling Item
Total revenue from contracts with customers	32	34	95	101
Service charges on deposit accounts \| Retail Bank
Segment Reporting, Revenue Reconciling Item
Total revenue from contracts with customers	14	15	41	43
Service charges on deposit accounts \| Wealth Management
Segment Reporting, Revenue Reconciling Item
Total revenue from contracts with customers	1	1	4	4
Service charges on deposit accounts \| Finance & Other
Segment Reporting, Revenue Reconciling Item
Total revenue from contracts with customers	0	0	0	0
Commercial loan servicing fees
Segment Reporting, Revenue Reconciling Item
Total revenue from contracts with customers	3	3	9	9
Commercial loan servicing fees \| Commercial Bank
Segment Reporting, Revenue Reconciling Item
Total revenue from contracts with customers	3	3	9	9
Commercial loan servicing fees \| Retail Bank
Segment Reporting, Revenue Reconciling Item
Total revenue from contracts with customers	0	0	0	0
Commercial loan servicing fees \| Wealth Management
Segment Reporting, Revenue Reconciling Item
Total revenue from contracts with customers	0	0	0	0
Commercial loan servicing fees \| Finance & Other
Segment Reporting, Revenue Reconciling Item
Total revenue from contracts with customers	0	0	0	0
Capital markets income
Segment Reporting, Revenue Reconciling Item
Total revenue from contracts with customers	4	3	12	8
Capital markets income \| Commercial Bank
Segment Reporting, Revenue Reconciling Item
Total revenue from contracts with customers	4	3	12	8
Capital markets income \| Retail Bank
Segment Reporting, Revenue Reconciling Item
Total revenue from contracts with customers	0	0	0	0
Capital markets income \| Wealth Management
Segment Reporting, Revenue Reconciling Item
Total revenue from contracts with customers	0	0	0	0
Capital markets income \| Finance & Other
Segment Reporting, Revenue Reconciling Item
Total revenue from contracts with customers	0	0	0	0
Brokerage fees
Segment Reporting, Revenue Reconciling Item
Total revenue from contracts with customers	6	6	22	14
Brokerage fees \| Commercial Bank
Segment Reporting, Revenue Reconciling Item
Total revenue from contracts with customers	0	0	0	0
Brokerage fees \| Retail Bank
Segment Reporting, Revenue Reconciling Item
Total revenue from contracts with customers	0	0	0	0
Brokerage fees \| Wealth Management
Segment Reporting, Revenue Reconciling Item
Total revenue from contracts with customers	8	6	24	14
Brokerage fees \| Finance & Other
Segment Reporting, Revenue Reconciling Item
Total revenue from contracts with customers	(2)	0	(2)	0
Other noninterest income
Segment Reporting, Revenue Reconciling Item
Total revenue from contracts with customers	11	11	32	34
Other noninterest income \| Commercial Bank
Segment Reporting, Revenue Reconciling Item
Total revenue from contracts with customers	0	1	1	3
Other noninterest income \| Retail Bank
Segment Reporting, Revenue Reconciling Item
Total revenue from contracts with customers	4	3	10	13
Other noninterest income \| Wealth Management
Segment Reporting, Revenue Reconciling Item
Total revenue from contracts with customers	7	7	20	18
Other noninterest income \| Finance & Other
Segment Reporting, Revenue Reconciling Item
Total revenue from contracts with customers	$ 0	$ 0	$ 1	$ 0

The total amount of noninterest income which may be derived from: (1) fees and commissions; (2) premiums earned; (3) insurance policy charges; (4) the sale or disposal of assets; and (5) other sources not otherwise specified.

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