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Transactions with Controlled Companies - Strategic Chemical Solutions Corp. (Details) - USD ($) $ in Thousands		3 Months Ended
	Dec. 31, 2025	Sep. 30, 2026	Sep. 30, 2025	Jun. 30, 2026
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]
Interest Income		$ 132,608	$ 152,394
Interest Receivable		23,039		$ 17,350
Reportable Legal Entities \| Subsidiaries \| Strategic Chemical Solutions Corp
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]
Interest Income		733	721
Interest Income Capitalized as PIK		564	$ 451
Interest Receivable		8		8
Other Receivables		$ 197		$ 197
Strategic Chemical Solutions Corp \| Reportable Legal Entities \| Subsidiaries
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]
Ownership interest		99.96%
Strategic Chemical Solutions Corp \| Term Loan A
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]
Principal amount	$ 0
Realized loss	35,568
Strategic Chemical Solutions Corp \| Term Loan B
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]
Principal amount	0
Realized loss	$ 30,651