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Fair Value Measurements - Narrative (Details) - USD ($) | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2021 | Sep. 30, 2020 | Sep. 30, 2021 | Sep. 30, 2020
Swap |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions |  |  |  |
Derivative, notional amount | $ 50,000,000 |  | $ 50,000,000 |
Investment expense | 244,000 | $ 178,000 | 724,000 |
Investment income, interest |  |  |  | $ 468,000
Swap 2 |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions |  |  |  |
Derivative, notional amount | $ 20,000,000 |  | $ 20,000,000 |

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