Commitments, Off-Balance Sheet Arrangements, Legal Proceedings and Regulatory Matters (Details Textuals) - USD ($)	3 Months Ended		9 Months Ended	12 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Dec. 31, 2024	Jan. 01, 2022
Other Commitments [Line Items]
Investment Program, Proportional Amortization Method, Elected, Impairment Loss			$ 0	$ 0
Loans Repurchased Under Make Whole Requests			$ 2,800,000	3,200,000
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					$ 3,800,000,000
Loans Sold To Outside Investors Remaining Outstanding Amount	$ 1,600,000,000		$ 1,600,000,000
SEC Schedule, 12-09, Valuation Allowances and Reserves, Amount	36,276,000		36,276,000	38,776,000
Financing Receivable, before Allowance for Credit Loss	30,951,964,000		30,951,964,000	29,768,586,000
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	600,000
Residential Mortgage [Member] | Recourse
Other Commitments [Line Items]
Financing Receivable, before Allowance for Credit Loss	9,600,000		9,600,000	13,700,000
Residential Mortgage [Member] | Recourse | Credit Risk
Other Commitments [Line Items]
Financing Receivable, before Allowance for Credit Loss	236,200,000		236,200,000	133,800,000
Loss on Sale of Investments			0
Affordable Housing Projects and Other [Member]
Other Commitments [Line Items]
Other Investments	183,500,000		183,500,000	204,800,000
Investment Program, Proportional Amortization Method, Applied, Amortization Expense	9,200,000	$ 8,500,000	26,300,000
Investment, Proportional Amortization Method, Elected, Amount	181,500,000		181,500,000	202,800,000
Accrued Liabilities	26,700,000		26,700,000	29,700,000
Loan Pool CRA Investments [Member]
Other Commitments [Line Items]
Other Investments	$ 61,700,000		$ 61,700,000	$ 54,100,000