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Borrowings (Narrative) (Details) - USD ($) |  |  | 1 Months Ended | 12 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | ---
Oct. 07, 2021 | Apr. 15, 2015 | Dec. 31, 2023 | May 31, 2023 | Dec. 31, 2023 | Jan. 31, 2023 | Dec. 31, 2022 | Apr. 30, 2022 | Oct. 07, 2020
Short Term And Long Term Borrowings [Line Items] |  |  |  |  |  |  |  |  |
Short -term Borrowings under FRB |  |  | $ 185,000,000 |  | $ 185,000,000 |  | $ 205,000,000 |  |
Short-term Borrowing funding bank name |  |  |  | FRB |  |  |  |  |
Short-term borrowings, weighted average rate |  |  | 5.29% |  | 5.29% |  | 4.60% |  |
Line of credit drawn amount |  |  | $ 0 |  | $ 0 |  | $ 0 |  |
FHLB Advances, Long term |  |  | 50,000,000 |  | $ 50,000,000 |  | 0 |  |
Debt instrument, maturity date |  |  |  |  | Jan. 20, 2026 |  |  |  |
2020 Notes [Member] |  |  |  |  |  |  |  |  |
Short Term And Long Term Borrowings [Line Items] |  |  |  |  |  |  |  |  |
Debt issuance cost amortization date |  |  |  |  | Oct. 15, 2025 |  |  |  |
2020 Notes [Member] | Private Placement [Member] |  |  |  |  |  |  |  |  |
Short Term And Long Term Borrowings [Line Items] |  |  |  |  |  |  |  |  |
Debt instrument, aggregate principal amount |  |  |  |  |  |  |  |  | $ 35,000,000
Debt instrument, maturity date | Oct. 15, 2030 |  |  |  |  |  |  |  |
Debt instrument, payment terms |  |  |  |  | The 2020 Notes have a maturity date of October 15, 2030 and bear interest, payable semi-annually, at the rate of 4.375% per annum, until October 15, 2025. Commencing on that date, the interest rate will reset quarterly to an interest rate per annum equal to the then current three-month secured overnight financing rate (“SOFR”) plus 4.265%, payable quarterly until maturity. |  |  |  |
Debt instrument, interest rate | 4.375% |  |  |  |  |  |  |  |
Debt issuance costs | $ 779,000 |  |  |  |  |  |  |  |
Proceeds from issuance of debt, net | $ 34,200,000 |  |  |  |  |  |  |  |
2020 Notes [Member] | Private Placement [Member] | Secured Overnight Financing Rate (“SOFR”) [Member] |  |  |  |  |  |  |  |  |
Short Term And Long Term Borrowings [Line Items] |  |  |  |  |  |  |  |  |
Debt instrument, percentage of basis spread on variable rate | 4.265% |  |  |  |  |  |  |  |
2015 Notes [Member] |  |  |  |  |  |  |  |  |
Short Term And Long Term Borrowings [Line Items] |  |  |  |  |  |  |  |  |
Debt instrument, aggregate principal amount |  | $ 40,000,000 |  |  |  |  |  |  |
Debt instrument, interest rate |  | 6.00% |  |  |  |  |  |  |
Debt issuance costs |  |  |  |  | $ 1,100,000 |  |  |  |
Proceeds from issuance of debt, net |  |  |  |  | $ 38,900,000 |  |  |  |
Number of years at stated rate |  |  |  |  | 10 years |  |  |  |
Debt issuance cost amortization date |  |  |  |  | Apr. 15, 2025 |  |  |  |
2015 Notes [Member] | Secured Overnight Financing Rate SOFR Chicago Mercantile Exchange [Member] |  |  |  |  |  |  |  |  |
Short Term And Long Term Borrowings [Line Items] |  |  |  |  |  |  |  |  |
Debt instrument, percentage of basis spread on variable rate |  | 4.20561% |  |  |  |  |  |  |
Commercial Bank [Member] |  |  |  |  |  |  |  |  |
Short Term And Long Term Borrowings [Line Items] |  |  |  |  |  |  |  |  |
Revolving line of credit allowing borrowings |  |  | 20,000,000 |  | $ 20,000,000 |  |  |  |
Federal Home Loan Borrowings Short Term Advances [Member] |  |  |  |  |  |  |  |  |
Short Term And Long Term Borrowings [Line Items] |  |  |  |  |  |  |  |  |
Short-term borrowings |  |  | 107,000,000 |  | 107,000,000 |  | 205,000,000 |  |
FHLB Advances, Long term |  |  | $ 50,000,000 |  | $ 50,000,000 |  |  |  |
FHLB, Advances interest rate |  |  | 4.05% |  | 4.05% |  |  |  |
Derivative, Fixed Interest Rate |  |  |  | 3.4615% |  | 3.669% |  | 0.787% |
Short term borrowings balance designated as cash flow hedge |  |  |  | $ 25,000,000 |  | $ 30,000,000 |  | $ 50,000,000 |
Federal Reserve Bank Advances [Member] |  |  |  |  |  |  |  |  |
Short Term And Long Term Borrowings [Line Items] |  |  |  |  |  |  |  |  |
Short-term borrowings |  |  | $ 78,000,000 |  | $ 78,000,000 |  | $ 0 |  |
4.80% Federal Reserve Bank Advances Member |  |  |  |  |  |  |  |  |
Short Term And Long Term Borrowings [Line Items] |  |  |  |  |  |  |  |  |
Short -term Borrowings under FRB |  |  |  | $ 15,000,000 |  |  |  |  |
Debt instrument, maturity date |  |  |  | May 08, 2024 |  |  |  |  |
FRB, Advances interest rate |  |  |  | 4.80% |  |  |  |  |
4.89 % Federal Reserve Bank Advances Member |  |  |  |  |  |  |  |  |
Short Term And Long Term Borrowings [Line Items] |  |  |  |  |  |  |  |  |
Short -term Borrowings under FRB |  |  | $ 50,000,000 |  | 50,000,000 |  |  |  |
Debt instrument, maturity date |  |  | Dec. 13, 2024 |  |  |  |  |  |
FRB, Advances interest rate |  |  | 4.89% |  |  |  |  |  |
4.88 % Federal Reserve Bank Advances Member |  |  |  |  |  |  |  |  |
Short Term And Long Term Borrowings [Line Items] |  |  |  |  |  |  |  |  |
Short -term Borrowings under FRB |  |  | $ 13,000,000 |  | $ 13,000,000 |  |  |  |
Debt instrument, maturity date |  |  | Dec. 20, 2024 |  |  |  |  |  |
FRB, Advances interest rate |  |  | 4.88% |  |  |  |  |  |

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