Loans - Commercial Banking: Risk Profile by Internal Risk Rating (Details) - USD ($) $ in Millions	Mar. 31, 2022	Dec. 31, 2021
Financing Receivable, Allowance for Credit Loss [Line Items]
Total	$ 280,466	$ 277,340
Commercial Banking
Financing Receivable, Allowance for Credit Loss [Line Items]
Term loans by vintage year one	9,554	19,811
Term loans by vintage year two	15,505	10,398
Term loans by vintage year three	8,856	10,239
Term loans by vintage year four	8,674	5,788
Term loans by vintage year five	5,236	2,919
Term loans by vintage after year five	10,243	8,492
Total term loans	58,068	57,647
Revolving loans	27,805	27,191
Revolving loans converted to term	301	84
Total	86,174	84,922
PPP loans	53	102
Commercial Banking \| Commercial and multifamily real estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Term loans by vintage year one	2,864	6,838
Term loans by vintage year two	5,562	3,119
Term loans by vintage year three	2,241	3,810
Term loans by vintage year four	3,432	2,738
Term loans by vintage year five	2,471	1,063
Term loans by vintage after year five	5,773	5,282
Total term loans	22,343	22,850
Revolving loans	11,891	12,387
Revolving loans converted to term	120	25
Total	34,354	35,262
Commercial Banking \| Commercial and multifamily real estate \| Noncriticized
Financing Receivable, Allowance for Credit Loss [Line Items]
Term loans by vintage year one	2,602	6,590
Term loans by vintage year two	5,454	2,924
Term loans by vintage year three	1,955	3,393
Term loans by vintage year four	2,922	2,401
Term loans by vintage year five	2,222	793
Term loans by vintage after year five	4,061	3,538
Total term loans	19,216	19,639
Revolving loans	11,831	12,286
Revolving loans converted to term	120	0
Total	31,167	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	262	248
Term loans by vintage year two	108	195
Term loans by vintage year three	286	329
Term loans by vintage year four	423	317
Term loans by vintage year five	230	261
Term loans by vintage after year five	1,483	1,478
Total term loans	2,792	2,828
Revolving loans	60	101
Revolving loans converted to term	0	25
Total	2,852	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	0	0
Term loans by vintage year two	0	0
Term loans by vintage year three	0	88
Term loans by vintage year four	87	20
Term loans by vintage year five	19	9
Term loans by vintage after year five	229	266
Total term loans	335	383
Revolving loans	0	0
Revolving loans converted to term	0	0
Total	335	383
Commercial Banking \| Commercial And Industrial [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Term loans by vintage year one	6,690	12,973
Term loans by vintage year two	9,943	7,279
Term loans by vintage year three	6,615	6,429
Term loans by vintage year four	5,242	3,050
Term loans by vintage year five	2,765	1,856
Term loans by vintage after year five	4,470	3,210
Total term loans	35,725	34,797
Revolving loans	15,914	14,804
Revolving loans converted to term	181	59
Total	51,820	49,660
Commercial Banking \| Commercial And Industrial [Member] \| Noncriticized
Financing Receivable, Allowance for Credit Loss [Line Items]
Term loans by vintage year one	6,318	12,662
Term loans by vintage year two	9,704	7,039
Term loans by vintage year three	6,415	5,506
Term loans by vintage year four	4,586	2,750
Term loans by vintage year five	2,527	1,730
Term loans by vintage after year five	4,269	3,033
Total term loans	33,819	32,720
Revolving loans	15,419	14,310
Revolving loans converted to term	181	59
Total	49,419	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	356	279
Term loans by vintage year two	220	188
Term loans by vintage year three	149	838
Term loans by vintage year four	508	207
Term loans by vintage year five	184	120
Term loans by vintage after year five	160	167
Total term loans	1,577	1,799
Revolving loans	464	456
Revolving loans converted to term	0	0
Total	2,041	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	16	32
Term loans by vintage year two	19	52
Term loans by vintage year three	51	85
Term loans by vintage year four	148	93
Term loans by vintage year five	54	6
Term loans by vintage after year five	41	10
Total term loans	329	278
Revolving loans	31	38
Revolving loans converted to term	0	0
Total	$ 360	$ 316

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