Loans - Commercial Banking: Risk Profile by Internal Risk Rating (Details) - USD ($) $ in Millions	Jun. 30, 2022	Dec. 31, 2021
Financing Receivable, Allowance for Credit Loss [Line Items]
Total	$ 296,384	$ 277,340
Commercial Banking
Financing Receivable, Allowance for Credit Loss [Line Items]
Term loans by vintage year one	18,982	19,811
Term loans by vintage year two	14,066	10,398
Term loans by vintage year three	7,680	10,239
Term loans by vintage year four	7,583	5,788
Term loans by vintage year five	4,571	2,919
Term loans by vintage after year five	9,138	8,492
Total term loans	62,020	57,647
Revolving loans	31,895	27,191
Revolving loans converted to term	58	84
Total	93,973	84,922
PPP loans	37	102
Commercial Banking \| Commercial and multifamily real estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Term loans by vintage year one	6,389	6,838
Term loans by vintage year two	5,107	3,119
Term loans by vintage year three	2,045	3,810
Term loans by vintage year four	2,994	2,738
Term loans by vintage year five	2,113	1,063
Term loans by vintage after year five	4,977	5,282
Total term loans	23,625	22,850
Revolving loans	14,195	12,387
Revolving loans converted to term	25	25
Total	37,845	35,262
Commercial Banking \| Commercial and multifamily real estate \| Noncriticized
Financing Receivable, Allowance for Credit Loss [Line Items]
Term loans by vintage year one	5,997	6,590
Term loans by vintage year two	4,866	2,924
Term loans by vintage year three	1,769	3,393
Term loans by vintage year four	2,602	2,401
Term loans by vintage year five	1,825	793
Term loans by vintage after year five	3,443	3,538
Total term loans	20,502	19,639
Revolving loans	14,144	12,286
Revolving loans converted to term	25	0
Total	34,671	31,925
Commercial Banking \| Commercial and multifamily real estate \| Criticized \| Criticized performing
Financing Receivable, Allowance for Credit Loss [Line Items]
Term loans by vintage year one	289	248
Term loans by vintage year two	241	195
Term loans by vintage year three	271	329
Term loans by vintage year four	385	317
Term loans by vintage year five	269	261
Term loans by vintage after year five	1,374	1,478
Total term loans	2,829	2,828
Revolving loans	51	101
Revolving loans converted to term	0	25
Total	2,880	2,954
Commercial Banking \| Commercial and multifamily real estate \| Criticized \| Criticized nonperforming
Financing Receivable, Allowance for Credit Loss [Line Items]
Term loans by vintage year one	103	0
Term loans by vintage year two	0	0
Term loans by vintage year three	5	88
Term loans by vintage year four	7	20
Term loans by vintage year five	19	9
Term loans by vintage after year five	160	266
Total term loans	294	383
Revolving loans	0	0
Revolving loans converted to term	0	0
Total	294	383
Commercial Banking \| Commercial And Industrial [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Term loans by vintage year one	12,593	12,973
Term loans by vintage year two	8,959	7,279
Term loans by vintage year three	5,635	6,429
Term loans by vintage year four	4,589	3,050
Term loans by vintage year five	2,458	1,856
Term loans by vintage after year five	4,161	3,210
Total term loans	38,395	34,797
Revolving loans	17,700	14,804
Revolving loans converted to term	33	59
Total	56,128	49,660
Commercial Banking \| Commercial And Industrial [Member] \| Noncriticized
Financing Receivable, Allowance for Credit Loss [Line Items]
Term loans by vintage year one	11,980	12,662
Term loans by vintage year two	8,692	7,039
Term loans by vintage year three	5,339	5,506
Term loans by vintage year four	4,115	2,750
Term loans by vintage year five	2,244	1,730
Term loans by vintage after year five	4,046	3,033
Total term loans	36,416	32,720
Revolving loans	17,229	14,310
Revolving loans converted to term	33	59
Total	53,678	47,089
Commercial Banking \| Commercial And Industrial [Member] \| Criticized \| Criticized performing
Financing Receivable, Allowance for Credit Loss [Line Items]
Term loans by vintage year one	518	279
Term loans by vintage year two	227	188
Term loans by vintage year three	276	838
Term loans by vintage year four	381	207
Term loans by vintage year five	172	120
Term loans by vintage after year five	97	167
Total term loans	1,671	1,799
Revolving loans	418	456
Revolving loans converted to term	0	0
Total	2,089	2,255
Commercial Banking \| Commercial And Industrial [Member] \| Criticized \| Criticized nonperforming
Financing Receivable, Allowance for Credit Loss [Line Items]
Term loans by vintage year one	95	32
Term loans by vintage year two	40	52
Term loans by vintage year three	20	85
Term loans by vintage year four	93	93
Term loans by vintage year five	42	6
Term loans by vintage after year five	18	10
Total term loans	308	278
Revolving loans	53	38
Revolving loans converted to term	0	0
Total	$ 361	$ 316

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