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Borrowings - Additional Information (Details) - USD ($) $ in Millions |  | 9 Months Ended |
--- | --- | --- | ---
Jun. 30, 2021 | Sep. 30, 2024 | Dec. 31, 2023
Federal Home Loan Bank, Advance, Branch of FHLBank [Line Items] |  |  |
Federal home loan bank, advances, general debt obligations, amount of available, unused funds |  | $ 89.8 |
Federal reserve bank advances, eligible borrowing capacity |  | 689.5 |
Securities [Member] |  |  |
Federal Home Loan Bank, Advance, Branch of FHLBank [Line Items] |  |  |
Federal home loan bank, advances, general debt obligations, disclosures, collateral pledged |  |  | $ 278.5
Federal reserve bank , general debt obligations, disclosures, collateral pledged |  | 515.7 | 526.4
Loans [Member] |  |  |
Federal Home Loan Bank, Advance, Branch of FHLBank [Line Items] |  |  |
Federal reserve bank , general debt obligations, disclosures, collateral pledged |  | 467.6 | 433.2
Agricultural and Residential Real Estate [Member] |  |  |
Federal Home Loan Bank, Advance, Branch of FHLBank [Line Items] |  |  |
Federal home loan bank, advances, general debt obligations, disclosures, collateral pledged |  | 201.0 | $ 191.1
Line of Credit [Member] |  |  |
Federal Home Loan Bank, Advance, Branch of FHLBank [Line Items] |  |  |
Line of Credit Facility, Maximum Borrowing Capacity | $ 20.0 |  |
Long-term line of credit |  | $ 0.0 |
Line of Credit [Member] | Minimum [Member] |  |  |
Federal Home Loan Bank, Advance, Branch of FHLBank [Line Items] |  |  |
Debt instrument, basis spread on variable rate | 3.25% | 8.00% |
Debt Instrument, Variable Interest Rate, Type [Extensible Enumeration] | Prime Rate [Member] | Prime Rate [Member] |

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- Definition Federal Reserve Bank advances, general debt obligations, amount of available, unused funds. + References No definition available. + Details
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- Definition Federal Reserve Bank , general debt obligations, disclosures, collateral pledged. + References No definition available. + Details
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- Definition Percentage points added to the reference rate to compute the variable rate on the debt instrument. + References No definition available. + Details
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- Definition Indicates type of variable interest rate on debt instrument. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 942 -SubTopic 470 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477734/942-470-50-3 + Details
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- Definition Amount of advances or credit lines available from the Federal Home Loan Bank (FHLB). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)(b)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 942 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(13)(3)(a)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478546/942-210-S99-1 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 942 -SubTopic 470 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147478878/942-470-45-1 + Details
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- Definition Amount of the collateral pledged in support of federal home loan bank advances outstanding. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 942 -SubTopic 470 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147478878/942-470-45-1 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 942 -SubTopic 470 -Section 50 -Paragraph 3 -Subparagraph (d) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477734/942-470-50-3 + Details
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- Definition 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. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)) -SubTopic 10 -Topic 210 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 942 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(16)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478546/942-210-S99-1 Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 944 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(16)(a)(2)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478777/944-210-S99-1 + Details
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