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Repurchase Agreements and Other Borrowings - Additional Information (Details) |  |  | 12 Months Ended |  |  |  |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Aug. 15, 2023 USD ($) Quarters shares | Oct. 06, 2020 USD ($) | Dec. 31, 2023 USD ($) | Dec. 31, 2022 USD ($) | Dec. 31, 2021 USD ($) | May 01, 2018 USD ($) | Sep. 08, 2016 USD ($) | Dec. 31, 2007 USD ($) | Apr. 26, 2006 USD ($)
Repurchase Agreements And Other Borrowings [Line Items] |  |  |  |  |  |  |  |  |
Federal Home Loan Bank Advances |  |  | $ 263,600,000 |  |  |  |  |  |
Repurchase agreements with customers |  |  | 213,721,000 | $ 221,414,000 |  |  |  |  |
Securities sold under agreements to repurchase increase (decrease) |  |  | $ (7,700,000) |  |  |  |  |  |
Securities sold under agreements to repurchase weighted average rate |  |  | 2.93% |  |  |  |  |  |
Subordinated Debentures |  |  | $ 106,755,000 | 94,553,000 |  |  |  |  |
Junior subordinated debentures, net |  |  | 24,058,000 | $ 19,364,000 |  |  |  |  |
Junior Subordinated Debentures |  |  |  |  |  |  |  |  |
Repurchase Agreements And Other Borrowings [Line Items] |  |  |  |  |  |  |  |  |
Junior subordinated debentures, net |  |  | $ 24,058,000 |  |  |  |  |  |
3.95% Subordinated Notes due 2030 |  |  |  |  |  |  |  |  |
Repurchase Agreements And Other Borrowings [Line Items] |  |  |  |  |  |  |  |  |
Aggregate principal amount |  | $ 96,000,000.0 |  |  |  |  |  |  |
Fixed-to-Floating Rate |  | 3.95% |  |  |  |  |  |  |
Maturity date |  | Oct. 15, 2030 |  |  |  |  |  |  |
Basis points |  | 3.83% |  |  |  |  |  |  |
Redemption description |  |  | The Company may, beginning with the interest payment date of October 15, 2025, and on any interest payment date thereafter, redeem the Notes, in whole or in part, at a redemption price equal to 100% of the principal amount of the Notes to be redeemed plus accrued and unpaid interest to but excluding the date of redemption. The Company may also redeem the Notes at any time, including prior to October 15, 2025, at the Company’s option, in whole but not in part, if: (i) a change or prospective change in law occurs that could prevent the Company from deducting interest payable on the Notes for U.S. federal income tax purposes; (ii) a subsequent event occurs that could preclude the Notes from being recognized as Tier 2 capital for regulatory capital purposes; or (iii) the Company is required to register as an investment company under the Investment Company Act of 1940, as amended; in each case, at a redemption price equal to 100% of the principal amount of the Notes plus any accrued and unpaid interest to but excluding the redemption date. |  |  |  |  |  |
3.95% Subordinated Notes due 2030 | SOFR |  |  |  |  |  |  |  |  |
Repurchase Agreements And Other Borrowings [Line Items] |  |  |  |  |  |  |  |  |
Description floating rate basis |  |  | three-month Term SOFR |  |  |  |  |  |
FMIS Trust II |  |  |  |  |  |  |  |  |
Repurchase Agreements And Other Borrowings [Line Items] |  |  |  |  |  |  |  |  |
Trust preferred securities issued |  |  |  |  |  |  |  |  | $ 10,000,000
Investment in statutory trust |  |  |  |  |  |  |  |  | $ 310,000
Junior subordinated debentures, net |  |  |  |  | $ 10,310,000 |  |  |  |
FMIS Trust II | Junior Subordinated Debentures |  |  |  |  |  |  |  |  |
Repurchase Agreements And Other Borrowings [Line Items] |  |  |  |  |  |  |  |  |
Fixed-to-Floating Rate |  |  | 7.25% | 6.37% |  |  |  |  |
Debt instrument, interest rate terms |  |  | bore interest at a fixed rate of 6.98% paid quarterly until June 15, 2011 and then converted to floating rate (LIBOR plus 160 basis points) after June 15, 2011 |  |  |  |  |  |
BHS Trust I |  |  |  |  |  |  |  |  |
Repurchase Agreements And Other Borrowings [Line Items] |  |  |  |  |  |  |  |  |
Number of consecutive quarters that interest payments on subordinated debentures may be deferred | Quarters | 20 |  |  |  |  |  |  |  |
Fixed-to-Floating Rate |  |  | 8.87% |  |  |  |  |  |
Basis points | 3.25% |  |  |  |  |  |  |  |
Preferred and Common Ownership Shares Issued | 100.00% |  |  |  |  |  |  |  |
Subordinated Debentures | $ 7,200,000 |  |  |  |  |  |  |  |
Redeeemed Subordinated Debentures |  |  |  |  |  |  |  | $ 6,200,000 |
Common Ownership Shares | shares | 217,000 |  |  |  |  |  |  |  |
Trust preferred securities issued | $ 7,000,000 |  |  |  |  |  |  |  |
Debt instrument, interest rate terms |  |  | three-month LIBOR |  |  |  |  |  |
BHS Trust II |  |  |  |  |  |  |  |  |
Repurchase Agreements And Other Borrowings [Line Items] |  |  |  |  |  |  |  |  |
Number of consecutive quarters that interest payments on subordinated debentures may be deferred | Quarters | 20 |  |  |  |  |  |  |  |
Fixed-to-Floating Rate |  |  | 7.69% |  |  |  |  |  |
Basis points | 2.05% |  |  |  |  |  |  |  |
Preferred and Common Ownership Shares Issued | 100.00% |  |  |  |  |  |  |  |
Subordinated Debentures | $ 4,100,000 |  |  |  |  |  |  |  |
Common Ownership Shares | shares | 124,000 |  |  |  |  |  |  |  |
Trust preferred securities issued | $ 4,000,000 |  |  |  |  |  |  |  |
Debt instrument, interest rate terms |  |  | three-month LIBOR |  |  |  |  |  |
CLS Trust I |  |  |  |  |  |  |  |  |
Repurchase Agreements And Other Borrowings [Line Items] |  |  |  |  |  |  |  |  |
Trust preferred securities issued |  |  |  |  |  |  | $ 4,000,000 |  |
Investment in statutory trust |  |  |  |  |  |  | $ 124,000 |  |
CLS Trust I | Junior Subordinated Debentures |  |  |  |  |  |  |  |  |
Repurchase Agreements And Other Borrowings [Line Items] |  |  |  |  |  |  |  |  |
Fixed-to-Floating Rate |  |  | 7.50% | 6.47% |  |  |  |  |
Debt instrument, interest rate terms |  |  | bear interest at three-month LIBOR plus 185 basis points |  |  |  |  |  |
FBTCST I |  |  |  |  |  |  |  |  |
Repurchase Agreements And Other Borrowings [Line Items] |  |  |  |  |  |  |  |  |
Trust preferred securities issued |  |  |  |  |  | $ 6,000,000 |  |  |
Investment in statutory trust |  |  |  |  |  | $ 186,000 |  |  |
FBTCST I | Junior Subordinated Debentures |  |  |  |  |  |  |  |  |
Repurchase Agreements And Other Borrowings [Line Items] |  |  |  |  |  |  |  |  |
Fixed-to-Floating Rate |  |  | 7.35% | 6.62% |  |  |  |  |
Debt instrument, interest rate terms |  |  | bear interest at three-month LIBOR plus 170 basis points |  |  |  |  |  |
Blackhawk |  |  |  |  |  |  |  |  |
Repurchase Agreements And Other Borrowings [Line Items] |  |  |  |  |  |  |  |  |
Aggregate principal amount | $ 15,000,000 |  |  |  |  |  |  |  |
Debt Instrument, Redemption Price, Percentage of Principal Amount Redeemed | 100.00% |  |  |  |  |  |  |  |
Blackhawk | 3.50% |  |  |  |  |  |  |  |  |
Repurchase Agreements And Other Borrowings [Line Items] |  |  |  |  |  |  |  |  |
Aggregate principal amount | $ 7,500,000 |  |  |  |  |  |  |  |
Interest rate (as a percent) | 3.50% |  |  |  |  |  |  |  |
Debt instrument, maturity month and year | 2031-05 |  |  |  |  |  |  |  |
Basis points | 2.85% |  |  |  |  |  |  |  |
Blackhawk | 3.50% | SOFR |  |  |  |  |  |  |  |  |
Repurchase Agreements And Other Borrowings [Line Items] |  |  |  |  |  |  |  |  |
Description floating rate basis |  |  | three-month SOFR |  |  |  |  |  |
Blackhawk | 3.875% |  |  |  |  |  |  |  |  |
Repurchase Agreements And Other Borrowings [Line Items] |  |  |  |  |  |  |  |  |
Aggregate principal amount | $ 7,500,000 |  |  |  |  |  |  |  |
Interest rate (as a percent) | 3.875% |  |  |  |  |  |  |  |
Debt instrument, maturity month and year | 2036-05 |  |  |  |  |  |  |  |
Basis points | 2.55% |  |  |  |  |  |  |  |
Blackhawk | 3.875% | SOFR |  |  |  |  |  |  |  |  |
Repurchase Agreements And Other Borrowings [Line Items] |  |  |  |  |  |  |  |  |
Description floating rate basis | three-month SOFR |  |  |  |  |  |  |  |
Revolving Credit Facility |  |  |  |  |  |  |  |  |
Repurchase Agreements And Other Borrowings [Line Items] |  |  |  |  |  |  |  |  |
Line of credit facility, maximum borrowing capacity |  |  | $ 15,000,000 |  |  |  |  |  |
Line of credit facility, interest rate spread |  |  | 2.25% |  |  |  |  |  |

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- Definition The increase (decrease) in the carrying value as of the balance sheet date of securities that an institution sells and agrees to repurchase (the identical or substantially the same securities) as a seller-borrower at a specified date for a specified price, also known as a repurchase agreement, or repo. Most repos involve obligations of the federal government or its agencies, but other financial instruments, such as commercial paper, banker's acceptances, and negotiable certificates of deposit, are sometimes used in repos. + References No definition available. + Details
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