Loans - Commercial Banking: Risk Profile by Internal Risk Rating (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Financing Receivable, Allowance for Credit Loss [Line Items]
Total	$ 277,340	$ 251,624
Commercial Banking
Financing Receivable, Allowance for Credit Loss [Line Items]
Term loans by vintage year one	19,811	14,262
Term loans by vintage year two	10,398	14,181
Term loans by vintage year three	10,239	8,366
Term loans by vintage year four	5,788	4,818
Term loans by vintage year five	2,919	3,990
Term loans by vintage after year five	8,492	9,561
Total term loans	57,647	55,178
Revolving loans	27,191	20,455
Revolving loans converted to term	84	147
Total	84,922	75,780
PPP loans	102	238
Commercial Banking \| Commercial and multifamily real estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Term loans by vintage year one	6,838	4,111
Term loans by vintage year two	3,119	5,389
Term loans by vintage year three	3,810	3,777
Term loans by vintage year four	2,738	1,798
Term loans by vintage year five	1,063	2,043
Term loans by vintage after year five	5,282	6,312
Total term loans	22,850	23,430
Revolving loans	12,387	7,226
Revolving loans converted to term	25	25
Total	35,262	30,681
Commercial Banking \| Commercial and multifamily real estate \| Noncriticized
Financing Receivable, Allowance for Credit Loss [Line Items]
Term loans by vintage year one	6,590	3,791
Term loans by vintage year two	2,924	4,932
Term loans by vintage year three	3,393	3,232
Term loans by vintage year four	2,401	1,437
Term loans by vintage year five	793	1,649
Term loans by vintage after year five	3,538	4,904
Total term loans	19,639	19,945
Revolving loans	12,286	7,114
Revolving loans converted to term	0	0
Total	31,925	27,059
Commercial Banking \| Commercial and multifamily real estate \| Criticized \| Criticized performing
Financing Receivable, Allowance for Credit Loss [Line Items]
Term loans by vintage year one	248	320
Term loans by vintage year two	195	446
Term loans by vintage year three	329	515
Term loans by vintage year four	317	355
Term loans by vintage year five	261	391
Term loans by vintage after year five	1,478	1,258
Total term loans	2,828	3,285
Revolving loans	101	112
Revolving loans converted to term	25	25
Total	2,954	3,422
Commercial Banking \| Commercial and multifamily real estate \| Criticized \| Criticized nonperforming
Financing Receivable, Allowance for Credit Loss [Line Items]
Term loans by vintage year one	0	0
Term loans by vintage year two	0	11
Term loans by vintage year three	88	30
Term loans by vintage year four	20	6
Term loans by vintage year five	9	3
Term loans by vintage after year five	266	150
Total term loans	383	200
Revolving loans	0	0
Revolving loans converted to term	0	0
Total	383	200
Commercial Banking \| Commercial And Industrial [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Term loans by vintage year one	12,973	10,151
Term loans by vintage year two	7,279	8,792
Term loans by vintage year three	6,429	4,589
Term loans by vintage year four	3,050	3,020
Term loans by vintage year five	1,856	1,947
Term loans by vintage after year five	3,210	3,249
Total term loans	34,797	31,748
Revolving loans	14,804	13,229
Revolving loans converted to term	59	122
Total	49,660	45,099
Commercial Banking \| Commercial And Industrial [Member] \| Noncriticized
Financing Receivable, Allowance for Credit Loss [Line Items]
Term loans by vintage year one	12,662	9,761
Term loans by vintage year two	7,039	7,890
Term loans by vintage year three	5,506	4,043
Term loans by vintage year four	2,750	2,717
Term loans by vintage year five	1,730	1,832
Term loans by vintage after year five	3,033	3,034
Total term loans	32,720	29,277
Revolving loans	14,310	11,548
Revolving loans converted to term	59	80
Total	47,089	40,905
Commercial Banking \| Commercial And Industrial [Member] \| Criticized \| Criticized performing
Financing Receivable, Allowance for Credit Loss [Line Items]
Term loans by vintage year one	279	316
Term loans by vintage year two	188	794
Term loans by vintage year three	838	521
Term loans by vintage year four	207	252
Term loans by vintage year five	120	106
Term loans by vintage after year five	167	215
Total term loans	1,799	2,204
Revolving loans	456	1,498
Revolving loans converted to term	0	42
Total	2,255	3,744
Commercial Banking \| Commercial And Industrial [Member] \| Criticized \| Criticized nonperforming
Financing Receivable, Allowance for Credit Loss [Line Items]
Term loans by vintage year one	32	74
Term loans by vintage year two	52	108
Term loans by vintage year three	85	25
Term loans by vintage year four	93	51
Term loans by vintage year five	6	9
Term loans by vintage after year five	10	0
Total term loans	278	267
Revolving loans	38	183
Revolving loans converted to term	0	0
Total	$ 316	$ 450

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