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Loans and Allowance for Credit Losses - Allowance for Credit Losses and Balances in Loan Portfolio (Details) - USD ($) | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2023 | Sep. 30, 2022 | Sep. 30, 2023 | Sep. 30, 2022 | Dec. 31, 2022
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Beginning balance | $ 14,582,000 | $ 7,416,000 | $ 7,619,000 | $ 7,688,000 |
Charge-offs | (261,000) | (175,000) | (532,000) | (560,000) |
Recoveries | 113,000 | 116,000 | 288,000 | 229,000 |
Provision | 438,000 | 100,000 | 332,000 | 100,000 |
Ending balance | 14,872,000 | 7,457,000 | 14,872,000 | 7,457,000 |
Individually evaluated for credit loss |  | 157,000 |  | 157,000 | $ 153,000
Collectively evaluated for credit loss |  | 7,300,000 |  | 7,300,000 | 7,466,000
Individually evaluated for credit loss | 484,000 |  | 484,000 |  |
Collectively evaluated for credit loss | 14,388,000 |  | 14,388,000 |  |
Individually evaluated for impairment |  |  |  |  | 2,846,000
Collectively evaluated for impairment |  |  |  |  | 1,172,662,000
Individually evaluated for credit loss | 3,148,000 |  | 3,148,000 |  |
Collectively evaluated for credit loss | 1,306,652,000 |  | 1,306,652,000 |  |
Acquired with deteriorated credit quality |  |  |  |  | 14,274,000
Loans | 1,309,800,000 |  | 1,309,800,000 |  | 1,189,782,000
Cumulative Effect of Change in Accounting Principle [Member] |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Beginning balance |  |  | 7,165,000 |  |
Agricultural [Member] |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Beginning balance | 78,000 | 132,000 | 144,000 | 448,000 |
Charge-offs | 0 | 0 | 0 | 0 |
Recoveries | 0 | 0 | 0 | 0 |
Provision | 5,000 | 8,000 | (75,000) | (308,000) |
Ending balance | 83,000 | 140,000 | 83,000 | 140,000 |
Individually evaluated for credit loss |  | 1,000 |  | 1,000 | 2,000
Collectively evaluated for credit loss |  | 139,000 |  | 139,000 | 142,000
Individually evaluated for credit loss | 3,000 |  | 3,000 |  |
Collectively evaluated for credit loss | 80,000 |  | 80,000 |  |
Individually evaluated for impairment |  |  |  |  | 23,000
Collectively evaluated for impairment |  |  |  |  | 64,136,000
Individually evaluated for credit loss | 65,000 |  | 65,000 |  |
Collectively evaluated for credit loss | 43,225,000 |  | 43,225,000 |  |
Acquired with deteriorated credit quality |  |  |  |  | 0
Loans | 43,290,000 |  | 43,290,000 |  | 64,159,000
Agricultural [Member] | Cumulative Effect of Change in Accounting Principle [Member] |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Beginning balance |  |  | 14,000 |  |
Commercial and Industrial [Member] |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Beginning balance | 2,896,000 | 1,613,000 | 1,361,000 | 1,454,000 |
Charge-offs | (73,000) | (47,000) | (73,000) | (177,000) |
Recoveries | 28,000 | 59,000 | 57,000 | 62,000 |
Provision | (328,000) | (252,000) | (409,000) | 34,000 |
Ending balance | 2,523,000 | 1,373,000 | 2,523,000 | 1,373,000 |
Individually evaluated for credit loss |  | 6,000 |  | 6,000 | 14,000
Collectively evaluated for credit loss |  | 1,367,000 |  | 1,367,000 | 1,347,000
Individually evaluated for credit loss | 89,000 |  | 89,000 |  |
Collectively evaluated for credit loss | 2,434,000 |  | 2,434,000 |  |
Individually evaluated for impairment |  |  |  |  | 177,000
Collectively evaluated for impairment |  |  |  |  | 206,074,000
Individually evaluated for credit loss | 269,000 |  | 269,000 |  |
Collectively evaluated for credit loss | 222,088,000 |  | 222,088,000 |  |
Acquired with deteriorated credit quality |  |  |  |  | 3,959,000
Loans | 222,357,000 |  | 222,357,000 |  | 210,210,000
Commercial and Industrial [Member] | Cumulative Effect of Change in Accounting Principle [Member] |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Beginning balance |  |  | 1,587,000 |  |
Consumer Portfolio Segment [Member] |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Beginning balance | 885,000 | 309,000 | 310,000 | 290,000 |
Charge-offs | (161,000) | (128,000) | (432,000) | (383,000) |
Recoveries | 80,000 | 56,000 | 208,000 | 162,000 |
Provision | 22,000 | 66,000 | 199,000 | 234,000 |
Ending balance | 826,000 | 303,000 | 826,000 | 303,000 |
Individually evaluated for credit loss |  | 1,000 |  | 1,000 | 1,000
Collectively evaluated for credit loss |  | 302,000 |  | 302,000 | 309,000
Individually evaluated for credit loss | 0 |  | 0 |  |
Collectively evaluated for credit loss | 826,000 |  | 826,000 |  |
Individually evaluated for impairment |  |  |  |  | 7,000
Collectively evaluated for impairment |  |  |  |  | 39,793,000
Individually evaluated for credit loss | 6,000 |  | 6,000 |  |
Collectively evaluated for credit loss | 37,599,000 |  | 37,599,000 |  |
Acquired with deteriorated credit quality |  |  |  |  | 8,000
Loans | 37,605,000 |  | 37,605,000 |  | 39,808,000
Consumer Portfolio Segment [Member] | Cumulative Effect of Change in Accounting Principle [Member] |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Beginning balance |  |  | 541,000 |  |
Commercial Real Estate Portfolio Segment [Member] |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Beginning balance | 7,237,000 | 4,224,000 | 4,822,000 | 3,705,000 |
Charge-offs | 0 | 0 | 0 | 0 |
Recoveries | 0 | 1,000 | 13,000 | 3,000 |
Provision | 908,000 | 384,000 | 304,000 | 901,000 |
Ending balance | 8,145,000 | 4,609,000 | 8,145,000 | 4,609,000 |
Individually evaluated for credit loss |  | 6,000 |  | 6,000 | 5,000
Collectively evaluated for credit loss |  | 4,603,000 |  | 4,603,000 | 4,817,000
Individually evaluated for credit loss | 347,000 |  | 347,000 |  |
Collectively evaluated for credit loss | 7,798,000 |  | 7,798,000 |  |
Individually evaluated for impairment |  |  |  |  | 165,000
Collectively evaluated for impairment |  |  |  |  | 622,131,000
Individually evaluated for credit loss | 1,070,000 |  | 1,070,000 |  |
Collectively evaluated for credit loss | 708,890,000 |  | 708,890,000 |  |
Acquired with deteriorated credit quality |  |  |  |  | 8,657,000
Loans | 709,960,000 |  | 709,960,000 |  | 630,953,000
Commercial Real Estate Portfolio Segment [Member] | Cumulative Effect of Change in Accounting Principle [Member] |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Beginning balance |  |  | 3,006,000 |  |
Construction Real Estate [Member] |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Beginning balance | 70,000 | 45,000 | 63,000 | 110,000 |
Charge-offs | 0 | 0 | 0 | 0 |
Recoveries | 0 | 0 | 0 |  |
Provision | (19,000) | 14,000 | (32,000) | (51,000) |
Ending balance | 51,000 | 59,000 | 51,000 | 59,000 |
Individually evaluated for credit loss |  | 0 |  | 0 | 0
Collectively evaluated for credit loss |  | 59,000 |  | 59,000 | 63,000
Individually evaluated for credit loss | 0 |  | 0 |  |
Collectively evaluated for credit loss | 51,000 |  | 51,000 |  |
Individually evaluated for impairment |  |  |  |  | 0
Collectively evaluated for impairment |  |  |  |  | 14,736,000
Individually evaluated for credit loss | 0 |  | 0 |  |
Collectively evaluated for credit loss | 16,477,000 |  | 16,477,000 |  |
Acquired with deteriorated credit quality |  |  |  |  | 0
Loans | 16,477,000 |  | 16,477,000 |  | 14,736,000
Construction Real Estate [Member] | Cumulative Effect of Change in Accounting Principle [Member] |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Beginning balance |  |  | 20,000 |  |
Residential Portfolio Segment [Member] |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Beginning balance | 3,376,000 | 691,000 | 906,000 | 671,000 |
Charge-offs | (27,000) | 0 | (27,000) |  |
Recoveries | 5,000 | 0 | 10,000 | 2,000 |
Provision | (150,000) | 178,000 | 305,000 | 196,000 |
Ending balance | 3,204,000 | 869,000 | 3,204,000 | 869,000 |
Individually evaluated for credit loss |  | 143,000 |  | 143,000 | 131,000
Collectively evaluated for credit loss |  | 726,000 |  | 726,000 | 775,000
Individually evaluated for credit loss | 45,000 |  | 45,000 |  |
Collectively evaluated for credit loss | 3,159,000 |  | 3,159,000 |  |
Individually evaluated for impairment |  |  |  |  | 2,474,000
Collectively evaluated for impairment |  |  |  |  | 225,792,000
Individually evaluated for credit loss | 1,738,000 |  | 1,738,000 |  |
Collectively evaluated for credit loss | 254,610,000 |  | 254,610,000 |  |
Acquired with deteriorated credit quality |  |  |  |  | 1,650,000
Loans | 256,348,000 |  | 256,348,000 |  | 229,916,000
Residential Portfolio Segment [Member] | Cumulative Effect of Change in Accounting Principle [Member] |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Beginning balance |  |  | 2,010,000 |  |
Loans To Other Financial Institutions [Member] |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Beginning balance | 40,000 |  |  |  |
Provision |  |  | 40,000 |  |
Ending balance | 40,000 |  | 40,000 |  |
Collectively evaluated for credit loss | 40,000 |  | 40,000 |  |
Collectively evaluated for credit loss | 23,763,000 |  | 23,763,000 |  |
Loans | 23,763,000 |  | 23,763,000 |  |
Unallocated Financing Receivables [Member] |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Beginning balance | 0 | 402,000 | 13,000 | 1,010,000 |
Charge-offs | 0 | 0 | 0 | 0 |
Recoveries | 0 | 0 | 0 | 0 |
Provision | 0 | (298,000) | 0 | (906,000) |
Ending balance | 0 | 104,000 | 0 | 104,000 |
Individually evaluated for credit loss |  | 0 |  | 0 | 0
Collectively evaluated for credit loss |  | $ 104,000 |  | $ 104,000 | $ 13,000
Individually evaluated for credit loss | 0 |  | 0 |  |
Collectively evaluated for credit loss | $ 0 |  | 0 |  |
Unallocated Financing Receivables [Member] | Cumulative Effect of Change in Accounting Principle [Member] |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Beginning balance |  |  | $ (13,000) |  |

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