Short Term Borrowings (Narrative) (Details) - USD ($)	9 Months Ended
Sep. 30, 2025	Dec. 31, 2024
Short-Term Debt [Line Items]
Short-term borrowings	$ 1,891,520,000	$ 639,015,000
Securities sold under agreements to repurchase	616,200,000	638,700,000
Federal funds purchased		300,000
FHLB Borrowings [Member]
Short-Term Debt [Line Items]
Short-term borrowings	$ 1,300,000,000	$ 0
Short-term borrowings, weighted average interest rate	4.22%
FHLB Borrowings [Member] \| Fixed Rate Notes One [Member]
Short-Term Debt [Line Items]
Short-term borrowings, maturity date	Oct. 01, 2025
FHLB Borrowings [Member] \| Fixed Rate Notes Two [Member]
Short-Term Debt [Line Items]
Short-term borrowings, maturity date	Nov. 03, 2025
FHLB Borrowings [Member] \| Fixed Rate Notes Three [Member]
Short-Term Debt [Line Items]
Short-term borrowings, maturity date	Dec. 01, 2025

Date when the debt instrument is scheduled to be fully repaid, in YYYY-MM-DD format.

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Amount of short term borrowing where a bank borrows, at the federal funds rate, from another bank.

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Amount, after the effects of master netting arrangements, of funds outstanding borrowed in the form of a security repurchase agreement between the entity and another party for the sale and repurchase of identical or substantially the same securities at a date certain for a specified price. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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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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Weighted average interest rate of short-term debt outstanding calculated at point in time.

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