Term Loans and Warrant Liabilities - Summary of Changes in Fair Value of Term Loan and First Amendment Term Loan Level 3 (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Change in fair value related to credit risk in other comprehensive income	$ 0	$ 820	$ 0	$ 820
Close Date Term Loan [Member] \| Level 3 [Member]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Balance			13,100	12,010
Change in fair value related to non-credit risk recorded within net loss			1,990	1,230
Change in fair value related to credit risk in other comprehensive income			0	(820)
Balance	15,090	12,420	$ 15,090	$ 12,420
Fair Value, Liability, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]			Other income, net	Other income, net
First Amendment Term Loan [Member] \| Level 3 [Member]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Balance			$ 4,910	$ 0
Transfer in			0	4,480
Change in fair value related to non-credit risk recorded within net loss			51	150
Payment			(4,961)	0
Balance	$ 0	$ 4,630	$ 0	$ 4,630
Fair Value, Liability, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]			Other income, net	Other income, net

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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