Commercial and investor real estate loans subject to charge offs, maximum.

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Cumulative effect from change in accounting guidance

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Days for certain equipment finance loans to be evaluated as potential charge off

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Days For Commercial and Industrial Loans To Be Evaluated As Potential Charge Off

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Days For Consumer Close-Ended Loans To Be Evaluated As Potential Charge Off

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Day sfor consumer first lien postion loans to be evaluated as a potential charge off

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Days for home equity loans in a second lien position to be evaluated as potential charge off

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Days for Consumer Loans in an Open-Ended Position to be Evaluated for Potential Charge Off

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Days for Credit Cards to be Evaluated for Potential Charge Off

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This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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Amount of investment in equity security without readily determinable fair value.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Term of lessee's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of investments classified as other.

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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Summary of Significant Accounting Policies (Narrative) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Accounting Policies [Abstract]
Gross equity method investments	$ 217,000,000	$ 198,000,000
Equity Securities without Readily Determinable Fair Value, Amount	64,000,000	65,000,000
Other Investments	281,000,000	$ 263,000,000
Financing Receivable, Modifications [Line Items]
Commercial And Investor Real Estate Loans Subject To Charge Offs Maximum	$ 250,000
Days For Commercial and Investor Real Estate Loans To Be Evaluated As Potential Charge Off	180 days
Days for certain equipment finance loans to be evaluated as potential charge off	120 days
Days For Consumer First Lien Postion Loans To Be Evaluated As Potential Charge Off	180 days
Days For Home Equity Loans In Second Lien Position To Be Evaluated As Potential Charge Off	120 days
Days For Consumer Close-Ended Loans To Be Evaluated As Potential Charge Off	120 days
Days for Consumer Loans in an Open-Ended Position to be Evaluated for Potential Charge Off	180 days
Days for Credit Cards to be Evaluated for Potential Charge Off	180 days
Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Modifications [Line Items]
Cumulative effect from change in accounting guidance			$ (5,000,000)	$ 28,000,000
Minimum [Member]
Financing Receivable, Modifications [Line Items]
Lessee, Operating Lease, Term of Contract	1 year
Maximum [Member]
Financing Receivable, Modifications [Line Items]
Lessee, Operating Lease, Term of Contract	20 years
Leasehold improvements \| Minimum [Member]
Financing Receivable, Modifications [Line Items]
Property, Plant and Equipment, Useful Life	7 years
Leasehold improvements \| Maximum [Member]
Financing Receivable, Modifications [Line Items]
Property, Plant and Equipment, Useful Life	40 years
Furniture and equipment \| Minimum [Member]
Financing Receivable, Modifications [Line Items]
Property, Plant and Equipment, Useful Life	3 years
Furniture and equipment \| Maximum [Member]
Financing Receivable, Modifications [Line Items]
Property, Plant and Equipment, Useful Life	10 years
Software \| Minimum [Member]
Financing Receivable, Modifications [Line Items]
Property, Plant and Equipment, Useful Life	5 years
Software \| Maximum [Member]
Financing Receivable, Modifications [Line Items]
Property, Plant and Equipment, Useful Life	20 years