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Business Combinations, Goodwill and Intangible Assets (Narrative) (Details) |  | 12 Months Ended |
--- | --- | --- | ---
Jan. 01, 2022 USD ($) bankingOffice $ / shares shares | Dec. 31, 2023 USD ($) bankingOffice | Dec. 31, 2022 USD ($) | Dec. 31, 2021 USD ($) bankingOffice | Dec. 31, 2020 USD ($)
Business Acquisition [Line Items] |  |  |  |  |
Number of banking offices | bankingOffice |  | 76 |  |  |
Total Assets |  | $ 6,152,198,000 | $ 6,155,991,000 | $ 5,608,539,000 |
Loans |  | 3,977,900,000 | 3,788,645,000 |  |
Goodwill |  | 180,357,000 | 180,357,000 | 121,761,000 | $ 121,956,000
Allowance for credit losses |  | 43,765,000 | 44,168,000 | 37,017,000 | $ 46,859,000
Decrease in goodwill attributable to sale of branches |  |  |  | 195,000 |
Goodwill impairment |  | 0 | 0 | 0 |
Amortization of expense intangible assets |  | 2,840,000 | 3,711,000 | $ 2,731,000 |
Disposal Group, Disposed of by Sale, Not Discontinued Operations | Brank Branches |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Number of branches sold (in banking offices) | bankingOffice |  |  |  | 2 |
Core Banking |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Goodwill |  | 179,025,000 | 179,025,000 | $ 120,429,000 |
Insurance |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Goodwill |  | 1,332,000 | $ 1,332,000 | $ 1,332,000 |
Citizens Union Bancorp of Shelbyville, Inc. ("CUB") |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Direct acquisition costs | $ 12,323,000 |  |  |  |
Goodwill | 58,596,000 |  |  |  |
Intangible Assets | 7,572,000 |  |  |  |
Cash paid | 50,800,000 |  |  |  |
Merger related costs |  | 12,323,000 |  |  |
Citizens Union Bancorp of Shelbyville, Inc. ("CUB") | Adjustment |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Allowance for credit losses |  | $ 6,300,000 |  |  |
Citizens Union Bancorp of Shelbyville, Inc. ("CUB") | Loans acquired with deteriorated credit quality |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Business Combination, Acquired Receivable, Fair Value | 29,868,000 |  |  |  |
Business Combination, Acquired Receivables, Gross Contractual Amount | 34,453,000 |  |  |  |
Estimated contractual cash flows of purchased financial asset with credit deterioration | $ 3,117,000 |  |  |  |
Citizens Union Bancorp of Shelbyville, Inc. ("CUB") | Common Stock |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Cash payment for each share exchanged (in dollars per share) | $ / shares | $ 13.44 |  |  |  |
Fixed exchange ratio (in shares) | shares | 0.7739 |  |  |  |
Shares of common stock issued for acquisition (in shares) | shares | 2,870,975 |  |  |  |
Citizens Union Bancorp of Shelbyville, Inc. ("CUB") | Core Deposit Intangible |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Intangible Assets | $ 7,572,000 |  |  |  |
Weighted average useful live of intangibles | 8 years |  |  |  |
Citizens Union Bancorp of Shelbyville, Inc. ("CUB") |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Number of banking offices | bankingOffice | 15 |  |  |  |
Citizens Union Bancorp of Shelbyville, Inc. ("CUB") | Citizens Union Bancorp of Shelbyville, Inc. ("CUB") |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Total Assets | $ 1,108,546,000 |  |  |  |
Loans | 683,807,000 |  |  |  |
Deposits | $ 930,533,000 |  |  |  |

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