Loans - Commercial Banking: Risk Profile by Internal Risk Rating (Details) - USD ($) $ in Millions	Sep. 30, 2022	Dec. 31, 2021
Financing Receivable, Allowance for Credit Loss [Line Items]
Total	$ 303,943	$ 277,340
Commercial Banking
Financing Receivable, Allowance for Credit Loss [Line Items]
Term loans by vintage year one	26,052	19,811
Term loans by vintage year two	12,734	10,398
Term loans by vintage year three	6,980	10,239
Term loans by vintage year four	5,953	5,788
Term loans by vintage year five	3,767	2,919
Term loans by vintage after year five	8,113	8,492
Total term loans	63,599	57,647
Revolving loans	32,178	27,191
Revolving loans converted to term	54	84
Total	95,831	84,922
PPP loans	32	102
Commercial Banking \| Commercial and multifamily real estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Term loans by vintage year one	8,416	6,838
Term loans by vintage year two	5,117	3,119
Term loans by vintage year three	1,909	3,810
Term loans by vintage year four	2,432	2,738
Term loans by vintage year five	1,835	1,063
Term loans by vintage after year five	4,492	5,282
Total term loans	24,201	22,850
Revolving loans	13,999	12,387
Revolving loans converted to term	25	25
Total	38,225	35,262
Commercial Banking \| Commercial and multifamily real estate \| Noncriticized
Financing Receivable, Allowance for Credit Loss [Line Items]
Term loans by vintage year one	7,785	6,590
Term loans by vintage year two	4,837	2,924
Term loans by vintage year three	1,748	3,393
Term loans by vintage year four	1,986	2,401
Term loans by vintage year five	1,502	793
Term loans by vintage after year five	3,237	3,538
Total term loans	21,095	19,639
Revolving loans	13,861	12,286
Revolving loans converted to term	25	0
Total	34,981	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	529	248
Term loans by vintage year two	280	195
Term loans by vintage year three	161	329
Term loans by vintage year four	439	317
Term loans by vintage year five	314	261
Term loans by vintage after year five	1,140	1,478
Total term loans	2,863	2,828
Revolving loans	138	101
Revolving loans converted to term	0	25
Total	3,001	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	102	0
Term loans by vintage year two	0	0
Term loans by vintage year three	0	88
Term loans by vintage year four	7	20
Term loans by vintage year five	19	9
Term loans by vintage after year five	115	266
Total term loans	243	383
Revolving loans	0	0
Revolving loans converted to term	0	0
Total	243	383
Commercial Banking \| Commercial And Industrial [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Term loans by vintage year one	17,636	12,973
Term loans by vintage year two	7,617	7,279
Term loans by vintage year three	5,071	6,429
Term loans by vintage year four	3,521	3,050
Term loans by vintage year five	1,932	1,856
Term loans by vintage after year five	3,621	3,210
Total term loans	39,398	34,797
Revolving loans	18,179	14,804
Revolving loans converted to term	29	59
Total	57,606	49,660
Commercial Banking \| Commercial And Industrial [Member] \| Noncriticized
Financing Receivable, Allowance for Credit Loss [Line Items]
Term loans by vintage year one	16,701	12,662
Term loans by vintage year two	7,028	7,039
Term loans by vintage year three	4,907	5,506
Term loans by vintage year four	3,186	2,750
Term loans by vintage year five	1,744	1,730
Term loans by vintage after year five	3,492	3,033
Total term loans	37,058	32,720
Revolving loans	17,491	14,310
Revolving loans converted to term	29	59
Total	54,578	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	787	279
Term loans by vintage year two	566	188
Term loans by vintage year three	158	838
Term loans by vintage year four	293	207
Term loans by vintage year five	147	120
Term loans by vintage after year five	123	167
Total term loans	2,074	1,799
Revolving loans	647	456
Revolving loans converted to term	0	0
Total	2,721	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	148	32
Term loans by vintage year two	23	52
Term loans by vintage year three	6	85
Term loans by vintage year four	42	93
Term loans by vintage year five	41	6
Term loans by vintage after year five	6	10
Total term loans	266	278
Revolving loans	41	38
Revolving loans converted to term	0	0
Total	$ 307	$ 316

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