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Borrowings - Unsecured Notes (Details) - USD ($) $ in Thousands |  |  |  |  |  |  | 3 Months Ended | 9 Months Ended |  |  |  |  |  |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Feb. 05, 2024 | Jun. 15, 2022 | Jan. 29, 2021 | Apr. 30, 2019 | Jul. 05, 2018 | Jan. 30, 2018 | Sep. 30, 2024 | Sep. 30, 2023 | Sep. 30, 2024 | Sep. 30, 2023 | Sep. 26, 2024 | Sep. 23, 2024 | Mar. 22, 2024 | Mar. 18, 2024 | Feb. 01, 2024 | Dec. 31, 2023 | Nov. 13, 2023 | Jan. 30, 2023
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Face amount |  |  |  |  |  |  | $ 300,000 |  | $ 300,000 |  |  |  |  |  |  |  |  |
Amortization of financing costs |  |  |  |  |  |  |  |  | 7,502 | $ 5,002 |  |  |  |  |  |  |  |
Unsecured notes outstanding balance |  |  |  |  |  |  | 993,577 |  | 993,577 |  |  |  |  |  |  | $ 506,500 |  |
Notional Amount |  |  |  |  |  |  | 600,000 |  | 600,000 |  |  |  |  |  |  |  |  |
Total net derivatives |  |  |  |  |  |  | 7,539 |  | 7,539 |  |  |  |  |  |  |  |  |
Derivative asset, subject to a master netting arrangement |  |  |  |  |  |  | 10,370 |  | 10,370 |  |  |  |  |  |  |  |  |
Unsecured Notes |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Interest expense |  |  |  |  |  |  | 12,277 | $ 4,644 | 33,765 | 15,602 |  |  |  |  |  |  |  |
Amortization of financing costs |  |  |  |  |  |  | 526 | 143 | 1,539 | 524 |  |  |  |  |  |  |  |
Amortization of debt discount (premium) |  |  |  |  |  |  | $ 165 | $ 0 | $ 422 | $ 0 |  |  |  |  |  |  |  |
Weighted average interest rate |  |  |  |  |  |  | 6.70% | 4.70% | 6.50% | 4.80% |  |  |  |  |  |  |  |
Effective interest rate |  |  |  |  |  |  | 7.30% | 4.90% | 7.00% | 5.00% |  |  |  |  |  |  |  |
Average debt outstanding |  |  |  |  |  |  | $ 706,304 | $ 391,500 | $ 676,414 | $ 433,661 |  |  |  |  |  |  |  |
Unsecured Notes | Minimum |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Face amount |  |  |  |  |  |  | $ 150,000 |  | $ 150,000 |  |  |  |  |  |  |  |  |
2018A Unsecured Notes | Unsecured Notes |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Face amount |  |  |  |  |  | $ 90,000 |  |  |  |  |  |  |  |  |  |  |  | $ 90,000
Term of debt |  |  |  |  |  | 5 years |  |  |  |  |  |  |  |  |  |  |  |
2018B Unsecured Notes | Unsecured Notes |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Face amount |  |  |  |  | $ 50,000 |  |  |  |  |  |  |  |  |  |  |  |  |
Term of debt |  |  |  |  | 5 years |  |  |  |  |  |  |  |  |  |  |  |  |
2019A Unsecured Notes | Unsecured Notes |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Face amount |  |  |  | $ 116,500 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Term of debt |  |  |  | 5 years |  |  |  |  |  |  |  |  |  |  |  |  |  |
Repayment of long-term debt | $ 116,500 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
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% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
8.25% Notes due 2028 | Unsecured Notes |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Face amount |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 115,000 |
Stated interest rate |  |  |  |  |  |  | 8.25% |  | 8.25% |  |  |  |  |  |  |  | 8.25% |
6.875% Notes due 2029 And 6.200% Notes due 2027 | Unsecured Notes |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total net derivatives |  |  |  |  |  |  | $ 7,539 |  | $ 7,539 |  |  |  |  |  |  |  |  |
Derivative asset, subject to a master netting arrangement |  |  |  |  |  |  | $ 10,370 |  | $ 10,370 |  |  |  |  |  |  |  |  |
6.875% Notes due 2029 | Unsecured Notes |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Face amount |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 300,000 |  |  |
Stated interest rate |  |  |  |  |  |  | 6.875% |  | 6.875% |  |  |  |  |  | 6.875% |  |  |
Derivative fixed interest rate |  |  |  |  |  |  | 6.875% |  | 6.875% |  |  |  | 6.875% | 6.875% |  |  |  |
Derivative floating interest rate |  |  |  |  |  |  |  |  |  |  |  |  | 2.8183% |  |  |  |  |
Notional Amount |  |  |  |  |  |  |  |  |  |  |  |  | $ 300,000 |  |  |  |  |
6.200% Notes due 2027 | Unsecured Notes |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Face amount |  |  |  |  |  |  |  |  |  |  | $ 300,000 |  |  |  |  |  |  |
Stated interest rate |  |  |  |  |  |  | 6.20% |  | 6.20% |  | 6.20% |  |  |  |  |  |  |
Derivative fixed interest rate |  |  |  |  |  |  | 6.20% |  | 6.20% |  | 6.20% | 6.20% |  |  |  |  |  |
Derivative floating interest rate |  |  |  |  |  |  |  |  |  |  |  | 2.882% |  |  |  |  |  |
Notional Amount |  |  |  |  |  |  |  |  |  |  |  | $ 300,000 |  |  |  |  |  |

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