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Fair Value Measurements - Unobservable Inputs (Details) $ in Thousands | Mar. 31, 2023 USD ($) | Dec. 31, 2022 USD ($)
--- | --- | ---
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fair Value | $ 9,626,202 | $ 9,617,248
Level 3 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fair Value | 9,426,489 | 9,472,796
First lien debt | Level 3 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fair Value | 9,225,290 | 9,275,511
First lien debt | Yield analysis | Level 3 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fair Value |  | 9,037,133
First lien debt | Yield analysis | Level 3 | Discount rate |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fair Value | 9,219,940 |
First lien debt | Market quotations | Level 3 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fair Value | $ 5,350 | $ 238,378
First lien debt | Low | Yield analysis | Level 3 | Discount rate |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Measurement input | 0.0639 | 0.0683
First lien debt | Low | Market quotations | Level 3 | Broker quoted price |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Measurement input | 0.9650 | 0.8200
First lien debt | High | Yield analysis | Level 3 | Discount rate |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Measurement input | 0.2062 | 0.1984
First lien debt | High | Market quotations | Level 3 | Broker quoted price |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Measurement input | 0.9650 | 0.9675
First lien debt | Weighted Average | Yield analysis | Level 3 | Discount rate |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Measurement input | 0.1003 | 0.1013
First lien debt | Weighted Average | Market quotations | Level 3 | Broker quoted price |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Measurement input | 0.9650 | 0.9419
Second lien debt | Yield analysis | Level 3 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fair Value | $ 46,678 | $ 46,336
Second lien debt | Low | Yield analysis | Level 3 | Discount rate |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Measurement input | 0.1015 | 0.1043
Second lien debt | High | Yield analysis | Level 3 | Discount rate |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Measurement input | 0.1398 | 0.1425
Second lien debt | Weighted Average | Yield analysis | Level 3 | Discount rate |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Measurement input | 0.1253 | 0.1260
Investments in equity | Level 3 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fair Value | $ 154,521 | $ 150,949
Investments in equity | Yield analysis | Level 3 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fair Value | 23,093 | 22,686
Investments in equity | Market quotations | Level 3 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fair Value | 105,862 | 105,782
Investments in equity | Option pricing model | Level 3 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fair Value | $ 25,566 | $ 22,481
Investments in equity | Low | Yield analysis | Level 3 | Discount rate |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Measurement input | 0.1167 | 0.1131
Investments in equity | Low | Market quotations | Level 3 | Performance multiple |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Measurement input | 5.70 | 5.50
Investments in equity | Low | Option pricing model | Level 3 | Expected volatility |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Measurement input | 0.3000 | 0.3000
Investments in equity | High | Yield analysis | Level 3 | Discount rate |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Measurement input | 0.1355 | 0.1375
Investments in equity | High | Market quotations | Level 3 | Performance multiple |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Measurement input | 39.66 | 29.00
Investments in equity | High | Option pricing model | Level 3 | Expected volatility |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Measurement input | 0.5000 | 0.5000
Investments in equity | Weighted Average | Yield analysis | Level 3 | Discount rate |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Measurement input | 0.1288 | 0.1274
Investments in equity | Weighted Average | Market quotations | Level 3 | Performance multiple |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Measurement input | 12.66 | 13.41
Investments in equity | Weighted Average | Option pricing model | Level 3 | Expected volatility |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Measurement input | 0.4180 | 0.4346

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