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Fair Value of Financial Instruments - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2023 | Jun. 30, 2022 | Jun. 30, 2023 | Jun. 30, 2022 | Dec. 31, 2022
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Unrealized Gain (Loss) on Investments | $ 18,858 | $ (48,316) | $ 39,963 | $ (85,058) |
2033 Notes |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Current Price Per Par Value | $ 24.7 |  | $ 24.7 |  | $ 24.59
2031 Asset-Backed Notes |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Current Price Per Par Value | 0.932 |  | $ 0.932 |  | $ 0.951
Debt | Unobservable Inputs Level 3 | Appreciation |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Unrealized Gain (Loss) on Investments |  |  | $ 23,000 | 17,700 |
Warrant Investment [Member] | Unobservable Inputs Level 3 | Depreciation [Member] |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Unrealized Gain (Loss) on Investments |  |  | (800) |  |
Warrant Investment [Member] | Unobservable Inputs Level 3 | Appreciation |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Unrealized Gain (Loss) on Investments |  |  |  | 8,600 |
Common Stock Investment [Member] | Unobservable Inputs Level 3 | Appreciation |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Unrealized Gain (Loss) on Investments |  |  | 8,300 | 10,200 |
Preferred Stock Investment Member | Unobservable Inputs Level 3 | Depreciation [Member] |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Unrealized Gain (Loss) on Investments |  |  | $ (1,700) | $ (14,900) |
Underwriting | 2033 Notes |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Current Price Per Par Value | $ 25 |  | $ 25 |  |

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