Amount at amortized cost, before allowance for credit loss, of collateral dependent loans and leases.

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Period of maturity extension and re-amortization of financing receivable modified for debtor experiencing financial difficulty, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Number of modified loans to borrowers experiencing financial difficulty during the period.

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Number of loans for which had payment deferral.

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Refers to the past due period after which a loan is considered in default, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Number of loans modified to borrowers with financial difficulty that defaulted after modification.

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Number of loans for which contractual term extended.

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Number of real estate borrowers.

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Unfunded lending commitments related to loans modified to borrowers experiencing financial difficulty.

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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 assets pledged to secure a debt instrument.

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Amortized cost of financing receivable with payment default in current period and modified within previous 12 months preceding payment default for debtor experiencing financial difficulty.

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Period of payment deferral of financing receivable modified for debtor experiencing financial difficulty, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Period of increase in weighted average maturity of financing receivable modified for debtor experiencing financial difficulty, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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Loans and Leases (Details)	3 Months Ended		9 Months Ended
Loans and Leases (Details)	Sep. 30, 2025 USD ($) Loan	Sep. 30, 2024 Loan	Sep. 30, 2025 USD ($) Loan Borrower	Sep. 30, 2024 Loan	Dec. 31, 2024 USD ($)
Loans and Leases [Abstract]
Remaining borrowing capacity (in Dollars)	$ 2,100,000,000		$ 2,100,000,000		$ 2,100,000,000
Unfunded loan commitments (in Dollars)	$ 0		$ 0
Number of loans modified (in Loan) \| Loan			1	0
Past due period for loan to be considered in default			90 days
Loans that were modified within last 12 months that had payment default (in Dollars)			$ 176,000
Number of loans modified to borrowers with financial difficulty that defaulted after modification. \| Loan	0	0	0	0
Collateral dependent loans and leases, amortized cost (in Dollars)	$ 0		$ 0		929,000
Residential and Home Equity [Member]
Loans and Leases [Abstract]
Number of loans modified (in Loan) \| Loan	1		1
Maturity extension and re-amortization term	10 years		10 years
Collateral dependent loans and leases, amortized cost (in Dollars)					0
Residential First Mortgage Loan [Member]
Loans and Leases [Abstract]
Number of loans modified (in Loan) \| Loan	1		1
Commercial Loan [Member]
Loans and Leases [Abstract]
Number of loans modified (in Loan) \| Loan			1
Maturity extension and re-amortization term	5 months		5 months
Agricultural Real Estate [Member]
Loans and Leases [Abstract]
Number of loans modified (in Loan) \| Loan			4
Collateral dependent loans and leases, amortized cost (in Dollars)					0
Agricultural [Member]
Loans and Leases [Abstract]
Number of real estate borrowers (in Borrower) \| Borrower			1
Number of loan, contractual term extended \| Loan			2
Number of loans, modified, had payment deferral \| Loan			3
Collateral dependent loans and leases, amortized cost (in Dollars)					$ 0
Federal Home Loan Bank [Member]
Loans and Leases [Abstract]
Collateral amount (in Dollars)	$ 1,200,000,000		$ 1,200,000,000
Remaining borrowing capacity (in Dollars)	805,900,000		805,900,000
Federal Reserve Bank [Member]
Loans and Leases [Abstract]
Collateral amount (in Dollars)	1,400,000,000		1,400,000,000
Remaining borrowing capacity (in Dollars)	$ 1,100,000,000		$ 1,100,000,000
Extended Maturity [Member] \| Agricultural [Member]
Loans and Leases [Abstract]
Contractual term extended			6 months
Payment Deferral [Member] \| Agricultural [Member]
Loans and Leases [Abstract]
Principal and interest deferrals period	6 months		6 months