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Fair Value of Financial Instruments - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2022 | Sep. 30, 2021 | Sep. 30, 2022 | Sep. 30, 2021 | Sep. 24, 2018
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Unrealized Gain (Loss) on Investments | $ (2,089) | $ (35,651) | $ (87,147) | $ 46,231 |
2033 Notes |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Current Price Per Par Value | $ 23.48 |  | $ 23.48 |  |
2031 Asset-Backed Notes |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Current Price Per Par Value | $ 0.970 |  | $ 0.970 |  |
Debt | Unobservable Inputs Level 3 | Depreciation [Member] |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Unrealized Gain (Loss) on Investments |  |  | $ (12,200) |  |
Debt | Unobservable Inputs Level 3 | Appreciation |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Unrealized Gain (Loss) on Investments |  |  |  | 400 |
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 |  |  | (13,400) |  |
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 |  |  |  | 8,000 |
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 |  |  | 9,500 | 15,600 |
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 |  |  | $ (23,200) | $ (6,500) |
Underwriting | 2033 Notes |  |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |  |
Current Price Per Par Value |  |  |  |  | $ 25.00

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