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Derivative Financial Instruments - Interest Swap Derivatives (Details) - USD ($) $ in Thousands | 1 Months Ended | 3 Months Ended | 6 Months Ended | 9 Months Ended | 12 Months Ended |
--- | --- | --- | --- | --- | --- | ---
Mar. 31, 2021 | Jun. 30, 2020 | Sep. 30, 2023 | Sep. 30, 2022 | Jun. 30, 2023 | Sep. 30, 2023 | Sep. 30, 2022 | Dec. 31, 2022 | Dec. 31, 2021
Derivative Instruments and Hedging Activities Disclosures [Line Items] |  |  |  |  |  |  |  |  |
Notional Value |  |  | $ 904 |  |  | $ 904 |  | $ 0 |
Fair Value |  |  | 81 |  |  | 81 |  | 0 |
Interest expense |  |  | 45,637 | $ 15,105 |  | 118,073 | $ 35,815 |  |
Payments for swap termination payments |  | $ 46,100 |  |  |  |  |  |  |
Cash pledged as collateral |  |  | 9,400 |  |  | 9,400 |  |  | $ 7,700
Derivatives designated as hedging instruments |  |  |  |  |  |  |  |  |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |  |  |  |  |  |  |  |  |
Fair value hedging adjustment |  |  |  |  | $ (2,088) | (1,707) |  |  |
Interest rate swaps | Derivatives designated as hedging instruments |  |  |  |  |  |  |  |  |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |  |  |  |  |  |  |  |  |
Notional Value |  |  | 50,000 |  |  | $ 50,000 |  | $ 50,000 |
Weighted Average Remaining Maturity (years) |  |  |  |  |  | 1 year 1 month 6 days |  | 1 year 9 months 18 days |
Fair Value |  |  | $ 1,717 |  |  | $ 1,717 |  | $ 2,093 |
Weighted-Average Rate |  |  | 2.33% |  |  | 2.33% |  | 2.33% |
Loans | Interest rate swaps | Derivatives designated as hedging instruments |  |  |  |  |  |  |  |  |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |  |  |  |  |  |  |  |  |
Weighted Average Remaining Maturity (years) |  |  |  |  |  | 10 years 7 months 6 days |  |  |
Securities available-for-sale | Interest rate swaps | Derivatives designated as hedging instruments |  |  |  |  |  |  |  |  |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |  |  |  |  |  |  |  |  |
Notional Value |  |  | $ 50,000 |  |  | $ 50,000 |  | $ 50,000 |
Weighted Average Remaining Maturity (years) |  |  |  |  |  | 1 year 1 month 6 days |  | 1 year 9 months 18 days |
Fair Value |  |  | $ 1,717 |  |  | $ 1,717 |  | $ 2,093 |
Weighted-Average Rate |  |  | 2.33% |  |  | 2.33% |  | 2.33% |
Payments for swap termination payments | $ 1,900 |  |  |  |  |  |  |  |
3-month SOFR | Interest rate swaps | Derivatives designated as hedging instruments |  |  |  |  |  |  |  |  |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |  |  |  |  |  |  |  |  |
Notional Value |  |  | $ 110,000 |  |  | $ 110,000 |  | $ 110,000 |
Weighted Average Remaining Maturity (years) |  |  |  |  |  | 3 years 3 months 18 days |  | 4 years 1 month 6 days |
Fair Value |  |  | $ 6,450 |  |  | $ 6,450 |  | $ 4,787 |
Derivative, variable interest rate |  |  | 2.88% |  |  | 2.88% |  | 2.88% |
1-month SOFR | Interest rate swaps | Derivatives designated as hedging instruments |  |  |  |  |  |  |  |  |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |  |  |  |  |  |  |  |  |
Notional Value |  |  | $ 20,000 |  |  | $ 20,000 |  | $ 60,000 |
Weighted Average Remaining Maturity (years) |  |  |  |  |  | 2 months 12 days |  | 7 months 6 days |
Fair Value |  |  | $ 85 |  |  | $ 85 |  | $ 735 |
Derivative, variable interest rate |  |  | 2.94% |  |  | 2.94% |  | 2.88% |
Fed Funds Effective | Interest rate swaps | Derivatives designated as hedging instruments |  |  |  |  |  |  |  |  |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |  |  |  |  |  |  |  |  |
Notional Value |  |  | $ 40,000 |  |  | $ 40,000 |  | $ 40,000 |
Weighted Average Remaining Maturity (years) |  |  |  |  |  | 8 months 12 days |  | 1 year 4 months 24 days |
Fair Value |  |  | $ 682 |  |  | $ 682 |  | $ 1,030 |
Derivative, variable interest rate |  |  | 2.78% |  |  | 2.78% |  | 2.78% |

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