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Business Combinations, Goodwill and Intangible Assets (Narrative) (Details) |  |  | 12 Months Ended |  |
--- | --- | --- | --- | --- | ---
Jul. 01, 2019 USD ($) banking_office $ / shares shares | Jun. 25, 2019 USD ($) | Dec. 31, 2021 USD ($) banking_office | Dec. 31, 2020 USD ($) | Dec. 31, 2019 USD ($) | Jun. 28, 2019 $ / shares | Dec. 31, 2018 USD ($)
Business Acquisition [Line Items] |  |  |  |  |  |  |
Number of banking offices | banking_office |  |  | 63 |  |  |  |
Assets |  |  | $ 5,608,539,000 | $ 4,977,577,000 | $ 4,397,672,000 |  |
Equity |  |  | 668,459,000 | 624,709,000 | 573,820,000 |  | $ 458,640,000
Goodwill |  |  | 121,761,000 | 121,956,000 | 121,306,000 |  | $ 103,681,000
Decrease in goodwill attributable to sale of branches |  |  | 195,000 | 0 | 0 |  |
Goodwill impairment |  |  | 0 |  |  |  |
Amortization of expense intangible assets |  |  | $ 2,731,000 | 3,539,000 | 3,721,000 |  |
Disposal Group, Disposed of by Sale, Not Discontinued Operations | Brank Branches |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |
Number of branches sold | banking_office |  |  | 2 |  |  |  |
Core Banking |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |
Goodwill |  |  | $ 120,429,000 | 120,624,000 | 119,974,000 |  |
Insurance |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |
Goodwill |  |  | $ 1,332,000 | 1,332,000 | $ 1,332,000 |  |
Citizens First |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |
Direct acquisition costs | $ 3,300,000 |  |  |  |  |  |
Goodwill | 17,739,000 |  |  |  |  |  |
Intangible Assets | 4,547,000 |  |  |  |  |  |
Goodwill non-deductible for tax purposes | $ 17,700,000 |  |  |  |  |  |
Cash portion, cash per share for common stock converted (USD per share) | $ / shares | $ 5.80 |  |  |  |  |  |
Number of the Company's common stock for each share converted (in shares) | shares | 0.6629 |  |  |  |  |  |
Shares of common stock issued for acquisition (in shares) | shares | 1,664,000 |  |  |  |  |  |
Total cash consideration paid, including options and fractional shares | $ 15,500,000 | $ 15,500,000 |  |  |  |  |
Additional goodwill recorded |  |  |  | $ 650,000 |  |  |
Citizens First | Non-impaired loans |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |
Fair value of non-impaired loans and customers receivables acquired | 349,900,000 |  |  |  |  |  |
Unpaid principal of non-impaired loans and customers receivables acquired | 353,300,000 |  |  |  |  |  |
Citizens First | CFB 401(k) Shares |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |
Cash portion, cash per share for common stock converted (USD per share) | $ / shares |  |  |  |  |  | $ 25.77 |
Additional cash paid for each shares acquired (in dollar per share) | $ / shares |  |  |  |  |  | $ 5.80 |
Citizens First | Core Deposit Intangible |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |
Intangible Assets | $ 4,500,000 |  |  |  |  |  |
Weighted average useful live of intangibles | 8 years |  |  |  |  |  |
Citizens First |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |
Number of banking offices | banking_office | 8 |  |  |  |  |  |
Assets | $ 456,000,000 |  |  |  |  |  |
Equity | $ 49,800,000 |  |  |  |  |  |

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