Segment Reporting (Segment Reporting Table) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Segment Reporting Information [Line Items]
Net interest income	$ 2,484	$ 2,504	$ 7,522	$ 7,477
Noninterest income	1,797	1,738	5,171	5,041
Total revenue	4,281	4,242	12,693	12,518
Provision for credit losses	52	183	3,429	552
Depreciation and amortization	246	247	737	738
Other noninterest expense	2,285	2,376	6,852	7,074
Income from continuing operations before income taxes and noncontrolling interests	1,698	1,436	1,675	4,154
Income taxes (benefit)	166	255	128	706
Net income from continuing operations	1,532	1,181	1,547	3,448
Average Assets	462,139	406,709	444,029	396,599
Retail Banking [Member]
Segment Reporting Information [Line Items]
Net interest income	1,383	1,393	4,229	4,118
Noninterest income	673	744	2,046	1,996
Total revenue	2,056	2,137	6,275	6,114
Provision for credit losses	(157)	147	1,049	356
Depreciation and amortization	64	60	188	170
Other noninterest expense	1,457	1,476	4,369	4,361
Income from continuing operations before income taxes and noncontrolling interests	692	454	669	1,227
Income taxes (benefit)	162	107	161	291
Net income from continuing operations	530	347	508	936
Average Assets	98,731	93,222	98,764	92,282
Corporate & Institutional Banking [Member]
Segment Reporting Information [Line Items]
Net interest income	1,012	911	3,014	2,685
Noninterest income	723	654	2,143	1,891
Total revenue	1,735	1,565	5,157	4,576
Provision for credit losses	211	48	2,254	219
Depreciation and amortization	50	51	149	151
Other noninterest expense	616	652	1,912	1,936
Income from continuing operations before income taxes and noncontrolling interests	858	814	842	2,270
Income taxes (benefit)	188	169	160	471
Net income from continuing operations	670	645	682	1,799
Average Assets	183,266	168,193	185,001	163,126
Asset Management Group [Member]
Segment Reporting Information [Line Items]
Net interest income	89	70	266	208
Noninterest income	221	216	629	719
Total revenue	310	286	895	927
Provision for credit losses	(19)	(1)	23	(2)
Depreciation and amortization	11	11	34	51
Other noninterest expense	200	217	613	656
Income from continuing operations before income taxes and noncontrolling interests	118	59	225	222
Income taxes (benefit)	27	13	52	51
Net income from continuing operations	91	46	173	171
Average Assets	8,361	7,331	8,041	7,247
Other [Member]
Segment Reporting Information [Line Items]
Net interest income	0	130	13	466
Noninterest income	180	124	353	435
Total revenue	180	254	366	901
Provision for credit losses	17	(11)	103	(21)
Depreciation and amortization	121	125	366	366
Other noninterest expense	12	31	(42)	121
Income from continuing operations before income taxes and noncontrolling interests	30	109	(61)	435
Income taxes (benefit)	(211)	(34)	(245)	(107)
Net income from continuing operations	241	143	184	542
Average Assets	$ 171,781	$ 137,963	$ 152,223	$ 133,944