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Fair Value Measurements - Unobservable Inputs (Details) $ in Thousands | Mar. 31, 2024 USD ($) | Dec. 31, 2023 USD ($)
--- | --- | ---
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fair Value | $ 10,439,173 | $ 9,868,440
Level 3 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fair Value | 10,330,365 | 9,710,582
First lien debt | Level 3 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fair Value | 10,178,311 | 9,564,203
First lien debt | Yield Analysis | Level 3 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fair Value | 10,082,833 | 9,533,700
First lien debt | Market Quotations | Level 3 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fair Value | 51,247 |
First lien debt | Asset Recoverability | Level 3 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fair Value | $ 44,231 | $ 30,503
First lien debt | Low | Yield Analysis | Level 3 | Discount Rate |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Measurement input | 0.0537 | 0.0768
First lien debt | Low | Market Quotations | Level 3 | Broker quoted price |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Measurement input | 100.00 |
First lien debt | Low | Asset Recoverability | Level 3 | Market Multiple |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Measurement input | 10 | 10.5
First lien debt | High | Yield Analysis | Level 3 | Discount Rate |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Measurement input | 0.3072 | 0.3089
First lien debt | High | Market Quotations | Level 3 | Broker quoted price |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Measurement input | 100.00 |
First lien debt | High | Asset Recoverability | Level 3 | Market Multiple |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Measurement input | 10.5 | 10.5
First lien debt | Weighted Average | Yield Analysis | Level 3 | Discount Rate |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Measurement input | 0.1058 | 0.1031
First lien debt | Weighted Average | Market Quotations | Level 3 | Broker quoted price |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Measurement input | 100.00 |
First lien debt | Weighted Average | Asset Recoverability | Level 3 | Market Multiple |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Measurement input | 10.34 | 10.5
Second lien debt | Yield Analysis | Level 3 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fair Value | $ 41,515 | $ 41,515
Second lien debt | Low | Yield Analysis | Level 3 | Discount Rate |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Measurement input | 0.0990 | 0.1018
Second lien debt | High | Yield Analysis | Level 3 | Discount Rate |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Measurement input | 0.1498 | 0.1438
Second lien debt | Weighted Average | Yield Analysis | Level 3 | Discount Rate |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Measurement input | 0.1307 | 0.1269
Unsecured debt | Yield Analysis | Level 3 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fair Value | $ 11,859 | $ 9,924
Unsecured debt | Low | Yield Analysis | Level 3 | Discount Rate |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Measurement input | 13.78 | 0.1490
Unsecured debt | High | Yield Analysis | Level 3 | Discount Rate |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Measurement input | 14 | 0.1490
Unsecured debt | Weighted Average | Yield Analysis | Level 3 | Discount Rate |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Measurement input | 13.97 | 0.1490
Investments in equity | Level 3 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fair Value | $ 98,680 | $ 94,940
Investments in equity | Yield Analysis | Level 3 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fair Value | 6,618 | 6,402
Investments in equity | Market Quotations | Level 3 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fair Value | 62,990 | 60,007
Investments in equity | Option Pricing Model | Level 3 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fair Value | $ 29,072 | $ 28,531
Investments in equity | Low | Yield Analysis | Level 3 | Discount Rate |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Measurement input | 0.1100 | 0.1075
Investments in equity | Low | Market Quotations | Level 3 | Performance Multiple |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Measurement input | 6.44 | 6.40
Investments in equity | Low | Option Pricing Model | Level 3 | Expected Volatility |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Measurement input | 0.3200 | 0.3200
Investments in equity | High | Yield Analysis | Level 3 | Discount Rate |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Measurement input | 0.1792 | 0.1792
Investments in equity | High | Market Quotations | Level 3 | Performance Multiple |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Measurement input | 30 | 30.00
Investments in equity | High | Option Pricing Model | Level 3 | Expected Volatility |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Measurement input | 0.5700 | 0.5500
Investments in equity | Weighted Average | Yield Analysis | Level 3 | Discount Rate |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Measurement input | 0.1434 | 0.1417
Investments in equity | Weighted Average | Market Quotations | Level 3 | Performance Multiple |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Measurement input | 11.59 | 11.47
Investments in equity | Weighted Average | Option Pricing Model | Level 3 | Expected Volatility |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Measurement input | 0.4306 | 0.4286

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