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Basis of Presentation (Details) - USD ($) |  | 6 Months Ended |  |  |  |  |
--- | --- | --- | --- | --- | --- | --- | ---
Jan. 01, 2023 | Jun. 30, 2023 | Mar. 31, 2023 | Dec. 31, 2022 | Jun. 30, 2022 | Mar. 31, 2022 | Dec. 31, 2021
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss |  | $ 12,833,000 | $ 12,640,000 | $ 9,850,000 | $ 9,700,000 | $ 9,204,000 | $ 9,103,000
Credit Loss, Financial Instrument |  | ACL - Loans: The ACL on loans is calculated in accordance with ASC 326 and is deducted from the amortized cost basis of loans to present our best estimate of the net amount expected to be collected. The ACL is established through a provision for credit losses charged to earnings. Loan losses are charged against the allowance when we believe the uncollectability of the loan balance is confirmed. Subsequent recoveries, if any, are credited to the allowance. We made an accounting policy election to exclude accrued interest receivable on loans from the estimate of credit losses. We evaluate the ACL on a regular basis. Our periodic review of the collectability of loans considers historical experience, the nature and volume of the loan portfolio, adverse situations that may affect the borrower’s ability to repay, estimated value of any underlying collateral, prevailing economic conditions, and reasonable and supportable forecasts. This evaluation is inherently subjective as it requires estimates that are susceptible to significant revision as more information becomes available. The ACL consists of a general component and loans individually analyzed. The general component covers loans not specifically analyzed and is based on historical loss experience, current conditions, and reasonable and supportable forecasts. The general component also includes uncertainties that we believe could affect our estimate of probable losses based on qualitative factors. Loans in nonaccrual status are individually analyzed on a loan-by-loan basis. Loans evaluated individually are not included in the general, or pooled, component of the ACL. For collateralized loans, the loan's specific allowance is measured by the fair value of the collateral approach. The specific reserve is based on the fair value of the collateral, less costs to sell if foreclosure is probable, and an allowance is established when the collateral value is lower than the carrying value of the loan. When the discounted cash flow method is used to measure the loan's specific allowance, the effective interest rate is used to discount expected cash flows to incorporate expected prepayments. An allowance is established when the discounted cash flows are lower than the carrying value of the loan. Large groups of smaller-balance, homogeneous loans are collectively evaluated for measurement of an allowance. Off Balance Sheet Credit Related Financial Instruments: In the ordinary course of business, we have entered into commitments to extend credit, including commitments under credit card arrangements, commercial lines of credit, home equity lines of credit, commercial letters of credit, and standby letters of credit. Such financial instruments are recorded only when funded. In connection with these commitments, we established an allowance for credit losses related to off-balance-sheet credit exposures. The allowance, recorded in a liability account, is calculated in accordance with ASC 326 and represents expected credit losses over the contractual period for which we are exposed to credit risk resulting from a contractual obligation to extend credit. The estimate of expected credit losses considers both the likelihood that funding will occur and the amount expected to be funded over the estimated remaining life of the commitment. The likelihood and expected amount of funding are based on historical utilization rates. No allowance is recognized if we have the unconditional right to cancel the obligation. The allowance is reported as a component of accrued interest payable and other liabilities in our consolidated balance sheets. Adjustments to the allowance are reported in our income statement as a component of provision for credit losses. |  |  |  |  |
Commercial Real Estate |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss |  | $ 5,968,000 | 6,036,000 | 461,000 |  |  |
Commercial [Member] |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss |  | 822,000 | 817,000 | 860,000 |  |  |
Agricultural [Member] |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss |  | 264,000 | 265,000 | 577,000 | 451,000 | 383,000 | 289,000
Residential Mortgage |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss |  | 4,173,000 | 4,113,000 | 617,000 | 639,000 | 725,000 | 747,000
Unallocated Financing Receivables [Member] |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss |  | 0 | $ 0 | $ 6,374,000 | $ 5,529,000 | $ 6,143,000 | $ 5,419,000
Cumulative Effect, Period of Adoption, Adjusted Balance |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss | $ 12,594,000 |  |  |  |  |  |
Cumulative Effect, Period of Adoption, Adjusted Balance | Commitments to Extend Credit |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |  |
Off-Balance-Sheet, Credit Loss, Liability | 315,000 |  |  |  |  |  |
Cumulative Effect, Period of Adoption, Adjusted Balance | Commercial Real Estate |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss | 5,993,000 |  |  |  |  |  |
Cumulative Effect, Period of Adoption, Adjusted Balance | Commercial [Member] |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss | 802,000 |  |  |  |  |  |
Cumulative Effect, Period of Adoption, Adjusted Balance | Agricultural [Member] |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss | 330,000 |  |  |  |  |  |
Cumulative Effect, Period of Adoption, Adjusted Balance | Residential Mortgage |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss | 4,152,000 |  |  |  |  |  |
Cumulative Effect, Period of Adoption, Adjusted Balance | Consumer Loan |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss | 1,317,000 |  |  |  |  |  |
Cumulative Effect, Period of Adoption, Adjusted Balance | Unallocated Financing Receivables [Member] |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss | 0 |  |  |  |  |  |
Accounting Standards Update 2016-13 |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss | 2,744,000 | 2,744,000 |  |  |  |  |
Accounting Standards Update 2016-13 | Commitments to Extend Credit |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |  |
Off-Balance-Sheet, Credit Loss, Liability | 315,000 |  |  |  |  |  |
Financing Receivable, Allowance for Credit Losses, Effect of Change in Method | (249,000) |  |  |  |  |  |
Accounting Standards Update 2016-13 | Loans Receivable |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Losses, Effect of Change in Method | (2,168,000) |  |  |  |  |  |
Accounting Standards Update 2016-13 | Commercial Real Estate |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss | 5,532,000 | 5,532,000 |  |  |  |  |
Financing Receivable, Allowance for Credit Losses, Effect of Change in Method | (4,370,000) |  |  |  |  |  |
Accounting Standards Update 2016-13 | Commercial [Member] |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss | (58,000) | (58,000) |  |  |  |  |
Financing Receivable, Allowance for Credit Losses, Effect of Change in Method | 46,000 |  |  |  |  |  |
Accounting Standards Update 2016-13 | Agricultural [Member] |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss | (247,000) | (247,000) |  |  |  |  |
Financing Receivable, Allowance for Credit Losses, Effect of Change in Method | 195,000 |  |  |  |  |  |
Accounting Standards Update 2016-13 | Residential Mortgage |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss | 3,535,000 | 3,535,000 |  |  |  |  |
Financing Receivable, Allowance for Credit Losses, Effect of Change in Method | (2,793,000) |  |  |  |  |  |
Accounting Standards Update 2016-13 | Consumer Loan |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss | 356,000 |  |  |  |  |  |
Financing Receivable, Allowance for Credit Losses, Effect of Change in Method | (281,000) |  |  |  |  |  |
Accounting Standards Update 2016-13 | Unallocated Financing Receivables [Member] |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss | (6,374,000) | $ (6,374,000) |  |  |  |  |
Financing Receivable, Allowance for Credit Losses, Effect of Change in Method | 5,035,000 |  |  |  |  |  |
Pre Adoption Allowance |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss | 9,850,000 |  |  |  |  |  |
Pre Adoption Allowance | Commitments to Extend Credit |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |  |
Off-Balance-Sheet, Credit Loss, Liability | 0 |  |  |  |  |  |
Pre Adoption Allowance | Commercial Real Estate |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss | 461,000 |  |  |  |  |  |
Pre Adoption Allowance | Commercial [Member] |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss | 860,000 |  |  |  |  |  |
Pre Adoption Allowance | Agricultural [Member] |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss | 577,000 |  |  |  |  |  |
Pre Adoption Allowance | Residential Mortgage |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss | 617,000 |  |  |  |  |  |
Pre Adoption Allowance | Consumer Loan |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss | 961,000 |  |  |  |  |  |
Pre Adoption Allowance | Unallocated Financing Receivables [Member] |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss | $ 6,374,000 |  |  |  |  |  |

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