Other Borrowed Funds - Narrative (Details)	Sep. 30, 2020 USD ($)
Federal Home Loan Bank, Advances [Line Items]
Federal home loan bank advances, maximum amount available	$ 430,700,000
Federal home loan bank advances, amount of available unused funds	416,900,000
Federal home loan bank advances, collateral pledged	577,100,000
Federal Reserve Bank
Federal Home Loan Bank, Advances [Line Items]
Line of credit facility, maximum borrowing capacity	95,700,000
Debt instrument, collateral amount	145,300,000
Various Unaffiliated Banks
Federal Home Loan Bank, Advances [Line Items]
Long-term line of credit	0
Line of credit facility, maximum borrowing capacity	60,000,000.0
Variable Rate Line of Credit
Federal Home Loan Bank, Advances [Line Items]
Federal home loan bank advances, maximum amount available	150,000,000.0
Long-term line of credit	$ 0

Amount of assets pledged to secure a debt instrument.

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

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Amount of the collateral pledged in support of federal home loan bank advances outstanding.

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

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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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No definition available.

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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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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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