Commitments and Contingencies - Narrative (Details) $ in Thousands, € in Millions	Jun. 30, 2026 USD ($)	Sep. 30, 2025 EUR (€)	Sep. 30, 2025 USD ($)
Other Commitments [Line Items]
Unfunded Commitment	$ 824,572		$ 931,496
Investment company, financial support to investee contractually required, not provided, amount that can be drawn immediately			$ 918,900
Portfolio Companies
Other Commitments [Line Items]
Unfunded Commitment	788,500
Equity investment in EDL JV
Other Commitments [Line Items]
Unfunded Commitment	$ 36,100	€ 41.7