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Allowance for Credit Losses (Collateral Dependent Loans and Leases) (Details) - USD ($) $ in Millions	Sep. 30, 2025	Dec. 31, 2024
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	$ 48,462	$ 37,681
Commercial real estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	28,620	19,567
Commercial real estate | Non-owner occupied term
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	8,444	6,278
Commercial real estate | Owner occupied term
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	7,361	5,270
Commercial
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	11,786	9,969
Commercial | Term
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	6,590	5,538
Commercial | Lines of credit & other
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	3,582	2,770
Commercial | Leases & equipment finance
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	1,614	1,661
Residential
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	7,875	7,965
Residential | Mortgage
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	5,722	5,933
Residential | Home equity loans & lines
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	2,153	2,032
Residential Real Estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	68	83
Residential Real Estate | Commercial real estate | Non-owner occupied term
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	0	0
Residential Real Estate | Commercial real estate | Owner occupied term
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	0	0
Residential Real Estate | Commercial | Term
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	0	2
Residential Real Estate | Commercial | Lines of credit & other
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	0	0
Residential Real Estate | Commercial | Leases & equipment finance
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	0	0
Residential Real Estate | Residential | Mortgage
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	66	79
Residential Real Estate | Residential | Home equity loans & lines
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	2	2
Commercial Real Estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	49	38
Commercial Real Estate | Commercial real estate | Non-owner occupied term
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	35	13
Commercial Real Estate | Commercial real estate | Owner occupied term
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	11	20
Commercial Real Estate | Commercial | Term
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	1	3
Commercial Real Estate | Commercial | Lines of credit & other
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	2	2
Commercial Real Estate | Commercial | Leases & equipment finance
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	0	0
Commercial Real Estate | Residential | Mortgage
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	0	0
Commercial Real Estate | Residential | Home equity loans & lines
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	0	0
General Business Assets
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	54	41
General Business Assets | Commercial real estate | Non-owner occupied term
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	0	0
General Business Assets | Commercial real estate | Owner occupied term
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	0	0
General Business Assets | Commercial | Term
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	17	16
General Business Assets | Commercial | Lines of credit & other
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	20	4
General Business Assets | Commercial | Leases & equipment finance
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	17	21
General Business Assets | Residential | Mortgage
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	0	0
General Business Assets | Residential | Home equity loans & lines
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	0	0
Total
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	171	162
Total | Commercial real estate | Non-owner occupied term
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	35	13
Total | Commercial real estate | Owner occupied term
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	11	20
Total | Commercial | Term
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	18	21
Total | Commercial | Lines of credit & other
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	22	6
Total | Commercial | Leases & equipment finance
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	17	21
Total | Residential | Mortgage
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	66	79
Total | Residential | Home equity loans & lines
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans and leases	$ 2	$ 2

X

- Definition

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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Reference 7: http://www.xbrl.org/2003/role/disclosureRef
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