Business Segments - Results of Operations and Average Assets by Segment (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Dec. 31, 2021	Dec. 31, 2020
Segment Reporting Information
Total goodwill	$ 4,925	$ 4,514	$ 4,925	$ 4,514	$ 4,514	$ 4,258
Total assets	205,463	207,731	205,463	207,731
Net interest income	1,498	1,189	4,032	3,574
Provision for (benefit from) credit losses	158	(42)	383	(330)
Net Interest Income After Provision for (Benefit from) Credit Losses	1,340	1,231	3,649	3,904
Noninterest Income
Service charges on deposits	143	152	449	445
Wealth and asset management revenue	141	147	430	436
Commercial banking revenue	134	152	406	465
Card and processing revenue	105	102	306	298
Leasing business revenue	60	78	179	226
Mortgage banking net revenue	69	86	152	235
Other noninterest income	59	120	195	211
Securities losses, net	(38)	(1)	(84)	12
Securities losses, net – non-qualifying hedges on MSRs	(1)	0	(2)	(2)
Total noninterest income	672	836	2,031	2,326
Noninterest Expense
Compensation and benefits	605	627	1,900	1,971
Technology and communications	106	98	306	285
Net occupancy expense	74	79	225	235
Equipment expense	36	34	108	102
Leasing business expense	33	33	95	102
Marketing expense	35	29	87	72
Card and processing expense	21	19	59	70
Other noninterest expense	257	253	721	704
Total noninterest expense	1,167	1,172	3,501	3,541
Income (loss) before income taxes	845	895	2,179	2,689
Applicable income tax expense (benefit)	192	191	470	582
Net Income	653	704	1,709	2,107
Impairment losses on bank premises	1	3	2	7
Impairment losses of operating lease equipment	0	0	2	25
Impairment losses and termination charges	0	1	2	3
Bank premises and equipment held for sale	24		24		24
Operating Segments | Commercial Banking
Segment Reporting Information
Total goodwill	2,324	1,981	2,324	1,981	1,980	1,980
Total assets	83,798	72,423	83,798	72,423
Net interest income	594	394	1,669	1,183
Provision for (benefit from) credit losses	(2)	(250)	44	(479)
Net Interest Income After Provision for (Benefit from) Credit Losses	596	644	1,625	1,662
Noninterest Income
Service charges on deposits	90	96	285	288
Wealth and asset management revenue	1	0	2	2
Commercial banking revenue	133	151	405	462
Card and processing revenue	22	21	65	57
Leasing business revenue	60	78	179	226
Mortgage banking net revenue	0	0	0	0
Other noninterest income	24	26	88	70
Securities losses, net	(32)	2	(32)	8
Securities losses, net – non-qualifying hedges on MSRs	0	0	0	0
Total noninterest income	298	374	992	1,113
Noninterest Expense
Compensation and benefits	147	152	483	475
Technology and communications	2	5	9	12
Net occupancy expense	10	9	30	28
Equipment expense	7	7	21	19
Leasing business expense	33	33	95	102
Marketing expense	1	1	3	4
Card and processing expense	3	2	8	5
Other noninterest expense	237	225	712	668
Total noninterest expense	440	434	1,361	1,313
Income (loss) before income taxes	454	584	1,256	1,462
Applicable income tax expense (benefit)	85	114	230	276
Net Income	369	470	1,026	1,186
Impairment losses of operating lease equipment			2	25
Operating Segments | Consumer and Small Business Banking
Segment Reporting Information
Total goodwill	2,375	2,302	2,375	2,302	2,303	2,047
Total assets	84,653	83,130	84,653	83,130
Net interest income	833	429	1,981	1,247
Provision for (benefit from) credit losses	34	19	93	95
Net Interest Income After Provision for (Benefit from) Credit Losses	799	410	1,888	1,152
Noninterest Income
Service charges on deposits	53	56	164	157
Wealth and asset management revenue	52	53	154	154
Commercial banking revenue	1	1	2	2
Card and processing revenue	79	78	231	232
Leasing business revenue	0	0	0	0
Mortgage banking net revenue	69	85	151	233
Other noninterest income	33	28	86	75
Securities losses, net	0	0	0	0
Securities losses, net – non-qualifying hedges on MSRs	(1)	0	(2)	(2)
Total noninterest income	286	301	786	851
Noninterest Expense
Compensation and benefits	207	207	630	633
Technology and communications	6	4	15	12
Net occupancy expense	49	49	147	149
Equipment expense	9	9	28	28
Leasing business expense	0	0	0	0
Marketing expense	20	11	44	26
Card and processing expense	19	18	54	68
Other noninterest expense	298	295	871	882
Total noninterest expense	608	593	1,789	1,798
Income (loss) before income taxes	477	118	885	205
Applicable income tax expense (benefit)	100	25	186	44
Net Income	377	93	699	161
Impairment losses on bank premises	1	3	2	6
Operating Segments | Wealth and Asset Management
Segment Reporting Information
Total goodwill	226	231	226	231	$ 231	$ 231
Total assets	12,232	11,272	12,232	11,272
Net interest income	79	22	167	64
Provision for (benefit from) credit losses	0	0	0	(1)
Net Interest Income After Provision for (Benefit from) Credit Losses	79	22	167	65
Noninterest Income
Service charges on deposits	0	0	1	0
Wealth and asset management revenue	132	140	407	414
Commercial banking revenue	1	0	1	1
Card and processing revenue	1	1	2	2
Leasing business revenue	0	0	0	0
Mortgage banking net revenue	0	1	1	2
Other noninterest income	0	1	0	3
Securities losses, net	0	0	0	0
Securities losses, net – non-qualifying hedges on MSRs	0	0	0	0
Total noninterest income	134	143	412	422
Noninterest Expense
Compensation and benefits	54	48	166	151
Technology and communications	0	0	1	1
Net occupancy expense	3	4	9	11
Equipment expense	0	0	0	0
Leasing business expense	0	0	0	0
Marketing expense	0	1	1	1
Card and processing expense	0	0	0	0
Other noninterest expense	85	81	244	236
Total noninterest expense	142	134	421	400
Income (loss) before income taxes	71	31	158	87
Applicable income tax expense (benefit)	15	7	33	19
Net Income	56	24	125	68
General Corporate and Other
Segment Reporting Information
Total goodwill	0	0	0	0
Total assets	24,780	40,906	24,780	40,906
Net interest income	(8)	344	215	1,080
Provision for (benefit from) credit losses	126	189	246	55
Net Interest Income After Provision for (Benefit from) Credit Losses	(134)	155	(31)	1,025
Noninterest Income
Service charges on deposits	0	0	(1)	0
Wealth and asset management revenue	0	0	0	0
Commercial banking revenue	(1)	0	(2)	0
Card and processing revenue	3	2	8	7
Leasing business revenue	0	0	0	0
Mortgage banking net revenue	0	0	0	0
Other noninterest income	2	65	21	63
Securities losses, net	(6)	(3)	(52)	4
Securities losses, net – non-qualifying hedges on MSRs	0	0	0	0
Total noninterest income	(2)	64	(26)	74
Noninterest Expense
Compensation and benefits	197	220	621	712
Technology and communications	98	89	281	260
Net occupancy expense	12	17	39	47
Equipment expense	20	18	59	55
Leasing business expense	0	0	0	0
Marketing expense	14	16	39	41
Card and processing expense	(1)	(1)	(3)	(3)
Other noninterest expense	(319)	(302)	(973)	(948)
Total noninterest expense	21	57	63	164
Income (loss) before income taxes	(157)	162	(120)	935
Applicable income tax expense (benefit)	(8)	45	21	243
Net Income	(149)	117	(141)	692
Impairment losses on bank premises				1
Bank premises and equipment held for sale	24	25	24	25
Eliminations
Segment Reporting Information
Total goodwill	0	0	0	0
Total assets	0	0	0	0
Net interest income	0	0	0	0
Provision for (benefit from) credit losses	0	0	0	0
Net Interest Income After Provision for (Benefit from) Credit Losses	0	0	0	0
Noninterest Income
Service charges on deposits	0	0	0	0
Wealth and asset management revenue	(44)	(46)	(133)	(134)
Commercial banking revenue	0	0	0	0
Card and processing revenue	0	0	0	0
Leasing business revenue	0	0	0	0
Mortgage banking net revenue	0	0	0	0
Other noninterest income	0	0	0	0
Securities losses, net	0	0	0	0
Securities losses, net – non-qualifying hedges on MSRs	0	0	0	0
Total noninterest income	(44)	(46)	(133)	(134)
Noninterest Expense
Compensation and benefits	0	0	0	0
Technology and communications	0	0	0	0
Net occupancy expense	0	0	0	0
Equipment expense	0	0	0	0
Leasing business expense	0	0	0	0
Marketing expense	0	0	0	0
Card and processing expense	0	0	0	0
Other noninterest expense	(44)	(46)	(133)	(134)
Total noninterest expense	(44)	(46)	(133)	(134)
Income (loss) before income taxes	0	0	0	0
Applicable income tax expense (benefit)	0	0	0	0
Net Income	$ 0	$ 0	$ 0	$ 0