Financing Agreement - Schedule of Interest Expense Recognized Related to Credit Facility (Details) - Secured Debt - Financing Agreement - Line of Credit - USD ($) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024	Sep. 30, 2024
Line of Credit Facility [Line Items]
Amortization of debt issuance costs	$ 420	$ 0	$ 1,533	$ 0
Accretion of the MOIC Payment	2,218	0	2,787	0	$ 0
Contractual interest expense	13,766	0	44,454	0
Total interest expense	$ 16,404	$ 0	$ 48,774	$ 0

Amount of noncash expense included in interest expense to amortize debt discount and premium associated with the related debt instruments. Excludes amortization of financing costs. Alternate captions include noncash interest expense.

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Amount of amortization expense attributable to debt issuance costs.

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Amount of the cost of borrowed funds accounted for as interest expense for debt.

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