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Borrowings - Unsecured Notes (Details) - USD ($) $ in Thousands |  |  |  |  |  |  |  |  |  |  |  | 12 Months Ended |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Jul. 14, 2022 | Jun. 15, 2022 | Mar. 08, 2021 | Feb. 16, 2021 | Jan. 29, 2021 | Apr. 30, 2019 | Sep. 25, 2018 | Jul. 05, 2018 | Jan. 30, 2018 | Jun. 30, 2017 | May 06, 2016 | Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018 | Oct. 17, 2018 | Sep. 30, 2016
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Face amount |  |  |  |  |  |  |  |  |  |  |  | $ 300,000 |  |  |  |  |  |
Repayment of Unsecured Notes |  |  |  |  |  |  |  |  |  |  |  | 55,000 | $ 141,750 | $ 0 |  |  |  |
Amortization of financing costs |  |  |  |  |  |  |  |  |  |  |  | 6,837 | 7,388 | 4,935 |  |  |  |
Unsecured Notes outstanding balance |  |  |  |  |  |  |  |  |  |  |  | 531,500 | 511,500 | 453,250 |  |  |  |
Unsecured Notes |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Interest expense |  |  |  |  |  |  |  |  |  |  |  | 25,033 | 24,401 | 23,839 |  |  |  |
Amortization of financing costs |  |  |  |  |  |  |  |  |  |  |  | $ 801 | $ 1,864 | $ 1,276 |  |  |  |
Weighted average interest rate |  |  |  |  |  |  |  |  |  |  |  | 4.80% | 4.70% | 5.30% |  |  |  |
Effective interest rate |  |  |  |  |  |  |  |  |  |  |  | 4.90% | 5.10% | 5.50% |  |  |  |
Average debt outstanding |  |  |  |  |  |  |  |  |  |  |  | $ 526,829 | $ 516,611 | $ 453,250 | $ 414,949 | $ 266,296 |  |
Unsecured Notes | Minimum |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Face amount |  |  |  |  |  |  |  |  |  |  |  | $ 150,000 |  |  |  |  |  |
2016 Unsecured Notes |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Repayment of Unsecured Notes |  |  |  | $ 90,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |
2016 Unsecured Notes | Unsecured Notes |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Face amount |  |  |  |  |  |  |  |  |  |  | $ 50,000 |  |  |  |  |  |  | $ 40,000
Term of debt |  |  |  |  |  |  |  |  |  |  | 5 years |  |  |  |  |  |  |
Stated interest rate |  |  |  |  |  |  |  |  |  |  | 5.313% |  |  |  |  |  |  |
2017A Unsecured Notes |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Repayment of Unsecured Notes | $ 55,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
2017A Unsecured Notes | Unsecured Notes |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Face amount |  |  |  |  |  |  |  |  |  | $ 55,000 |  |  |  |  |  |  |  |
Term of debt |  |  |  |  |  |  |  |  |  | 5 years |  |  |  |  |  |  |  |
Stated interest rate |  |  |  |  |  |  |  |  |  | 4.76% |  |  |  |  |  |  |  |
2018A Unsecured Notes | Unsecured Notes |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Face amount |  |  |  |  |  |  |  |  | $ 90,000 |  |  |  |  |  |  |  |  |
Term of debt |  |  |  |  |  |  |  |  | 5 years |  |  |  |  |  |  |  |  |
Stated interest rate |  |  |  |  |  |  |  |  | 4.87% |  |  |  |  |  |  |  |  |
2018B Unsecured Notes | Unsecured Notes |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Face amount |  |  |  |  |  |  |  | $ 50,000 |  |  |  |  |  |  |  |  |  |
Term of debt |  |  |  |  |  |  |  | 5 years |  |  |  |  |  |  |  |  |  |
Stated interest rate |  |  |  |  |  |  |  | 5.36% |  |  |  |  |  |  |  |  |  |
2019A Unsecured Notes | Unsecured Notes |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Face amount |  |  |  |  |  | $ 116,500 |  |  |  |  |  |  |  |  |  |  |  |
Term of debt |  |  |  |  |  | 5 years |  |  |  |  |  |  |  |  |  |  |  |
Stated interest rate |  |  |  |  |  | 5.494% |  |  |  |  |  |  |  |  |  |  |  |
2021A Unsecured Notes | Unsecured Notes |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Face amount |  |  |  |  | $ 200,000 |  |  |  |  |  |  |  |  |  |  |  |  |
Term of debt |  |  |  |  | 5 years |  |  |  |  |  |  |  |  |  |  |  |  |
Stated interest rate |  |  |  |  | 3.875% |  |  |  |  |  |  |  |  |  |  |  |  |
2022A Unsecured Notes | Unsecured Notes |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Face amount |  | $ 75,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Term of debt |  | 5 years |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stated interest rate |  | 5.90% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
5.75% Unsecured Notes | Unsecured Notes |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Face amount |  |  |  |  |  |  | $ 50,000 |  |  |  |  |  |  |  |  |  | $ 1,750 |
Term of debt |  |  |  |  |  |  | 5 years |  |  |  |  |  |  |  |  |  |  |
Stated interest rate |  |  |  |  |  |  | 5.75% |  |  |  |  |  |  |  |  |  |  |
Redemption of principal |  |  | $ 51,750 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Redemption as a percentage of principal |  |  | 100.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |

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