Short-Term Debt and Long-Term Debt (Narrative) (Details) - USD ($)	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023
Debt Instrument [Line Items]
Net Of Unamortized Prepayment Penalties	$ 439,000	$ 988,000
Financing receivables	2,996,259,000	3,279,708,000
Securities pledged as collateral	$ 0	0
Maximum ratio of debt to total assets under debt covenant	50.00%
Maximum total debt under debt covenant	$ 1,799,000,000
Repayments of Federal Home Loan Bank of New York Advances	18,000,000	150,000,000
Outstanding Borrowings	0	0
Federal Home Loan Bank Borrowings [Member]
Debt Instrument [Line Items]
Additional funding	135,700,000
Federal Reserve Discount [Member]
Debt Instrument [Line Items]
Additional funding	333,000,000.0
Asset Pledged as Collateral [Member] \| Federal Home Loan Bank Borrowings [Member]
Debt Instrument [Line Items]
Financing receivables	1,400,000,000	1,700,000,000
Asset Pledged as Collateral [Member] \| Federal Reserve Discount [Member]
Debt Instrument [Line Items]
Financing receivables	$ 546,700,000	$ 497,400,000

Maximum ratio of debt to total assets under debt covenant.

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Maximum total debt under debt covenant.

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Net Of Unamortized Prepayment Penalties

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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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Amount of restricted investment in debt security measured at fair value with change in fair value recognized in net income (trading).

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Amount of advances or credit lines available from the Federal Home Loan Bank (FHLB).

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Amortized cost, after allowance for credit loss, of financing receivable. Excludes financing receivable covered under loss sharing agreement and net investment in lease.

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Amount of cash outflow for repayment of Federal Home Loan Bank (FHLBank) borrowing, classified as financing activity.

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