Investment Valuations and Fair Value Measurements - Summary of Valuation Techniques and Quantitative Information in Determining Fair value of Level 3 Investments (Details) - Level 3 $ in Thousands	Sep. 30, 2025 USD ($)	Dec. 31, 2024 USD ($)
Debt \| Income Method \| Discount Rate
Investment Valuations And Fair Value Measurements [Line Items]
Fair Value	$ 978,868	$ 889,873
Debt \| Income Method \| Discount Rate \| Minimum
Investment Valuations And Fair Value Measurements [Line Items]
Debt securities, measurement input	7.4	10.3
Debt \| Income Method \| Discount Rate \| Maximum
Investment Valuations And Fair Value Measurements [Line Items]
Debt securities, measurement input	18.8	22.2
Debt \| Income Method \| Discount Rate \| Weighted Average
Investment Valuations And Fair Value Measurements [Line Items]
Debt securities, measurement input	11.6	13
Debt \| Market Method
Investment Valuations And Fair Value Measurements [Line Items]
Fair Value	$ 53,778
Debt \| Market Method \| EBITDA Multiple
Investment Valuations And Fair Value Measurements [Line Items]
Fair Value	$ 130,544	$ 52,030
Debt \| Market Method \| EBITDA Multiple \| Minimum
Investment Valuations And Fair Value Measurements [Line Items]
Debt securities, measurement input	4.5	6.5
Debt \| Market Method \| EBITDA Multiple \| Maximum
Investment Valuations And Fair Value Measurements [Line Items]
Debt securities, measurement input	9	8
Debt \| Market Method \| EBITDA Multiple \| Weighted Average
Investment Valuations And Fair Value Measurements [Line Items]
Debt securities, measurement input	7.2	7.1
Debt \| Market Method \| Indicative Bid
Investment Valuations And Fair Value Measurements [Line Items]
Fair Value	$ 49,967
Debt \| Market Method \| Indicative Bid \| Minimum
Investment Valuations And Fair Value Measurements [Line Items]
Debt securities, measurement input	97.6
Debt \| Market Method \| Indicative Bid \| Maximum
Investment Valuations And Fair Value Measurements [Line Items]
Debt securities, measurement input	97.6
Debt \| Market Method \| Indicative Bid \| Weighted Average
Investment Valuations And Fair Value Measurements [Line Items]
Debt securities, measurement input	97.6
Debt \| Income Method \| Discount Rate
Investment Valuations And Fair Value Measurements [Line Items]
Fair Value	$ 90,608
Debt \| Income Method \| Discount Rate \| Minimum
Investment Valuations And Fair Value Measurements [Line Items]
Debt securities, measurement input	9.4
Debt \| Income Method \| Discount Rate \| Maximum
Investment Valuations And Fair Value Measurements [Line Items]
Debt securities, measurement input	18.2
Debt \| Income Method \| Discount Rate \| Weighted Average
Investment Valuations And Fair Value Measurements [Line Items]
Debt securities, measurement input	12.1
Debt \| Market Method
Investment Valuations And Fair Value Measurements [Line Items]
Fair Value	$ 35,502
Debt \| Income Method \| Discount Rate
Investment Valuations And Fair Value Measurements [Line Items]
Fair Value	$ 21,858
Debt \| Income Method \| Discount Rate \| Minimum
Investment Valuations And Fair Value Measurements [Line Items]
Debt securities, measurement input	18.5
Debt \| Income Method \| Discount Rate \| Maximum
Investment Valuations And Fair Value Measurements [Line Items]
Debt securities, measurement input	24.5
Debt \| Income Method \| Discount Rate \| Weighted Average
Investment Valuations And Fair Value Measurements [Line Items]
Debt securities, measurement input	21.5
Debt \| Market Method \| EBITDA Multiple \| Minimum
Investment Valuations And Fair Value Measurements [Line Items]
Debt securities, measurement input	4
Debt \| Market Method \| EBITDA Multiple \| Maximum
Investment Valuations And Fair Value Measurements [Line Items]
Debt securities, measurement input	5
Debt \| Market Method \| EBITDA Multiple \| Weighted Average
Investment Valuations And Fair Value Measurements [Line Items]
Debt securities, measurement input	4.5
Debt \| Market Method \| Revenue Multiple \| Minimum
Investment Valuations And Fair Value Measurements [Line Items]
Debt securities, measurement input	0.4
Debt \| Market Method \| Revenue Multiple \| Maximum
Investment Valuations And Fair Value Measurements [Line Items]
Debt securities, measurement input	0.5
Debt \| Market Method \| Revenue Multiple \| Weighted Average
Investment Valuations And Fair Value Measurements [Line Items]
Debt securities, measurement input	0.4
Debt \| Market Method \| Indicative Bid \| Minimum
Investment Valuations And Fair Value Measurements [Line Items]
Debt securities, measurement input	101
Debt \| Market Method \| Indicative Bid \| Maximum
Investment Valuations And Fair Value Measurements [Line Items]
Debt securities, measurement input	101.2
Debt \| Market Method \| Indicative Bid \| Weighted Average
Investment Valuations And Fair Value Measurements [Line Items]
Debt securities, measurement input	101.2
Equity \| Market Method \| EBITDA Multiple
Investment Valuations And Fair Value Measurements [Line Items]
Fair Value	$ 38,746	$ 224
Equity \| Market Method \| EBITDA Multiple \| Minimum
Investment Valuations And Fair Value Measurements [Line Items]
Equity securities, measurement input	4.5	5.8
Equity \| Market Method \| EBITDA Multiple \| Maximum
Investment Valuations And Fair Value Measurements [Line Items]
Equity securities, measurement input	9	7.5
Equity \| Market Method \| EBITDA Multiple \| Weighted Average
Investment Valuations And Fair Value Measurements [Line Items]
Equity securities, measurement input	8.5	6.8

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