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Loans Sold To Outside Investors Loss Reimbursement Settlement Paid

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No definition available.

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Loans sold to outside investors original amount

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Loans sold to outside investors remaining outstanding amount

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No definition available.

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Make Whole Requests, Loan Origination Date, Majority

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No definition available.

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Amount of impairment loss for investment that generates income tax credit and other income tax benefit under tax credit program elected to be accounted for using proportional amortization method. Includes, but is not limited to, investment under tax credit program not meeting condition for accounting under proportional amortization method.

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Amount of investment that generates income tax credit and other income tax benefit under tax credit program elected to be accounted for using proportional amortization method. Includes, but is not limited to, investment under program not meeting condition for accounting under proportional amortization method.

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Amount of amortization expense for investment that generates income tax credit and other income tax benefit under tax credit program accounted for using proportional amortization method.

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The difference between the carrying value and the sale price of an investment. A loss would be recognized when the sale price of the investment is less than the carrying value of the investment. This element refers to the Loss included in earnings and not to the cash proceeds of the sale.

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

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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 investments classified as other.

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Amount of commitment and contingent commitment, including amount of delayed equity contribution, for investment that generates income tax credit and other income tax benefit under tax credit program elected to be accounted for using proportional amortization method. Includes, but is not limited to, commitment and contingent commitment related to investment under tax credit program not meeting condition for accounting under proportional amortization method.

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Amount of valuation and qualifying accounts and reserves.

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Commitments, Off-Balance Sheet Arrangements, Legal Proceedings and Regulatory Matters (Details Textuals) - USD ($)	3 Months Ended			9 Months Ended		12 Months Ended
	Sep. 30, 2026	Mar. 31, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025	Dec. 31, 2025	Jan. 01, 2022
Other Commitments [Line Items]
Investment Program, Proportional Amortization Method, Elected, Impairment Loss	$ 0		$ 0		$ 0
Loans Repurchased Under Make Whole Requests				$ 4,300,000		$ 3,500,000
Loans Sold To Outside Investors Loss Reimbursement Settlement Paid		$ 0
Make Whole Requests, Loan Origination Date, Majority				Jan. 01, 2022
Loans Sold To Outside Investors Original Amount							$ 4,500,000,000
Loans Sold To Outside Investors Remaining Outstanding Amount	2,100,000,000			$ 2,100,000,000
SEC Schedule, 12-09, Valuation Allowances and Reserves, Amount	49,744,000			49,744,000		41,276,000
Financing Receivable, before Allowance for Credit Loss	36,519,871,000			36,519,871,000		31,163,614,000
Loss on Sale of Investments		$ 0
Residential Mortgage [Member]
Other Commitments [Line Items]
SEC Schedule, 12-09, Valuation Allowances and Reserves, Amount	500,000			500,000		300,000
Residential Mortgage [Member] \| Recourse
Other Commitments [Line Items]
Financing Receivable, before Allowance for Credit Loss	12,700,000			12,700,000		11,400,000
Residential Mortgage [Member] \| Recourse \| Credit Risk
Other Commitments [Line Items]
Financing Receivable, before Allowance for Credit Loss	419,000,000.0			419,000,000.0		273,400,000
Loss on Sale of Investments				0
Affordable Housing Projects and Other [Member]
Other Commitments [Line Items]
Other Investments	167,000,000.0			167,000,000.0		174,300,000
Investment Program, Proportional Amortization Method, Applied, Amortization Expense	8,476,000		$ 9,249,000	25,623,000	$ 26,307,000
Investment, Proportional Amortization Method, Elected, Amount	165,900,000			165,900,000		172,200,000
Investment Program, Proportional Amortization Method, Elected, Impairment Loss				0
Investment Program, Proportional Amortization Method, Elected, Commitment	34,100,000			34,100,000		22,800,000
Loan Pool CRA Investments [Member]
Other Commitments [Line Items]
Other Investments	$ 75,900,000			$ 75,900,000		$ 62,300,000