Segment Reporting (Segment Reporting Table) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Segment Reporting Information [Line Items]
Net interest income	$ 2,504	$ 2,466	$ 7,477	$ 7,240
Noninterest income	1,989	1,891	5,741	5,552
Total revenue	4,493	4,357	13,218	12,792
Provision for credit losses (benefit)	183	88	552	260
Depreciation and amortization	247	224	738	694
Other noninterest expense	2,376	2,384	7,074	7,025
Income before income taxes and noncontrolling interests	1,687	1,661	4,854	4,813
Income taxes (benefit)	295	261	817	818
Net income	1,392	1,400	4,037	3,995
Average Assets	406,709	377,877	396,599	376,599
Retail Banking [Member]
Segment Reporting Information [Line Items]
Net interest income	1,393	1,305	4,118	3,800
Noninterest income	744	622	1,996	1,935
Total revenue	2,137	1,927	6,114	5,735
Provision for credit losses (benefit)	147	113	356	254
Depreciation and amortization	60	52	170	144
Other noninterest expense	1,476	1,462	4,361	4,347
Income before income taxes and noncontrolling interests	454	300	1,227	990
Income taxes (benefit)	107	73	291	239
Net income	347	227	936	751
Average Assets	93,222	89,963	92,282	89,259
Corporate & Institutional Banking [Member]
Segment Reporting Information [Line Items]
Net interest income	911	903	2,685	2,641
Noninterest income	654	592	1,891	1,774
Total revenue	1,565	1,495	4,576	4,415
Provision for credit losses (benefit)	48	(13)	219	43
Depreciation and amortization	51	47	151	140
Other noninterest expense	652	651	1,936	1,879
Income before income taxes and noncontrolling interests	814	810	2,270	2,353
Income taxes (benefit)	169	168	471	496
Net income	645	642	1,799	1,857
Average Assets	168,193	153,897	163,126	153,149
Asset Management Group [Member]
Segment Reporting Information [Line Items]
Net interest income	70	71	208	217
Noninterest income	216	228	719	676
Total revenue	286	299	927	893
Provision for credit losses (benefit)	(1)	2	(2)	2
Depreciation and amortization	11	13	51	38
Other noninterest expense	217	212	656	643
Income before income taxes and noncontrolling interests	59	72	222	210
Income taxes (benefit)	13	17	51	50
Net income	46	55	171	160
Average Assets	7,331	7,397	7,247	7,455
BlackRock [Member]
Segment Reporting Information [Line Items]
Noninterest income	251	265	708	732
Total revenue	251	265	708	732
Income before income taxes and noncontrolling interests	251	265	708	732
Income taxes (benefit)	40	49	111	124
Net income	211	216	597	608
Average Assets	8,321	7,964	8,321	7,964
Other [Member]
Segment Reporting Information [Line Items]
Net interest income	130	187	466	582
Noninterest income	124	184	427	435
Total revenue	254	371	893	1,017
Provision for credit losses (benefit)	(11)	(14)	(21)	(39)
Depreciation and amortization	125	112	366	372
Other noninterest expense	31	59	121	156
Income before income taxes and noncontrolling interests	109	214	427	528
Income taxes (benefit)	(34)	(46)	(107)	(91)
Net income	143	260	534	619
Average Assets	$ 129,642	$ 118,656	$ 125,623	$ 118,772