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v3.23.2

Basis of Accounting and Consolidation - Additional Information (Details) - USD ($) |  |  | 3 Months Ended | 6 Months Ended |
--- | --- | --- | --- | --- | ---
Mar. 21, 2023 | Feb. 14, 2022 | Jun. 30, 2023 | Jun. 30, 2022 | Jun. 30, 2023 | Jun. 30, 2022 | Dec. 31, 2022
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |
Common stock, par value (in dollars per share) |  |  | $ 4 |  | $ 4 |  | $ 4
Deposits |  |  | $ 5,219,585,000 |  | $ 5,219,585,000 |  | $ 5,257,001,000
Stock plans, term |  |  |  |  | 10 years |  |
Maximum number of shares to be issued in stock incentive plan (in shares) |  |  | 399,983 |  | 399,983 |  |
Employee discount for employee stock purchase plan |  |  |  |  | 15.00% |  |
Employee stock purchase plan, number of shares authorized |  |  | 600,000 |  | 600,000 |  |
Stock issued during period, shares, employee stock purchase plans |  |  | 9,175 | 5,177 | 17,138 | 8,326 |
Captive maximum gross premiums |  |  |  |  | $ 2,650,000 |  |
Employee Stock Option |  |  |  |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |
Common stock awarded in SI plan (in shares) |  |  |  |  | 0 |  |
Restricted Stock |  |  |  |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |
Common stock awarded in SI plan (in shares) |  |  |  |  | 59,950 | 61,400 |
Restricted Stock Units (RSUs) |  |  |  |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |
Common stock awarded in SI plan (in shares) |  |  |  |  | 37,900 | 37,150 |
Blackhawk Bancorp, Inc |  |  |  |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |
Percentage of issued and outstanding shares acquired | 100.00% |  |  |  |  |  |
Common stock, par value (in dollars per share) | $ 0.01 |  |  |  |  |  |
Conversion of common stock | 1.15 |  |  |  |  |  |
Share Price | $ 4 |  |  |  |  |  |
Consideration payable in shares | 3,330,176 |  |  |  |  |  |
Delta Bancshares Company |  |  |  |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |
Percentage of issued and outstanding shares acquired |  | 100.00% |  |  |  |  |
Common stock, par value (in dollars per share) |  | $ 10.00 |  |  |  |  |
Share Price |  | $ 4.00 |  |  |  |  |
Consideration payable in cash |  | $ 15,150,000 |  |  |  |  |
Consideration payable in shares |  | 2,292,270 |  |  |  |  |

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