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v3.25.2

Concentrations of Credit Risk - Additional Information (Detail) $ in Thousands | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | ---
Jun. 30, 2025 USD ($) | Jun. 30, 2024 | Jun. 30, 2025 USD ($) | Jun. 30, 2024 | Sep. 30, 2024 USD ($) Vendor | Sep. 30, 2023 USD ($) | Sep. 30, 2022
Concentration Risk [Line Items] |  |  |  |  |  |  |
Restricted cash | $ 3,048 |  | $ 3,048 |  | $ 3,009 | $ 3,132 |
Outstanding letters of credit to be collateralized by amounts on deposit | 3,000 |  | 3,000 |  | 3,000 | 3,100 |
Allowance for doubtful accounts | $ 0 |  | $ 0 |  | $ 0 | $ 0 |
Number of vendors represents more than ten percentage of purchases | Vendor |  |  |  |  | 2 |  |
AAR {Member] |  |  |  |  |  |  |
Concentration Risk [Line Items] |  |  |  |  |  |  |
Percentage of purchases during year |  |  |  |  | 18.00% |  |
Standard Aero Holdings, Inc. [Member] |  |  |  |  |  |  |
Concentration Risk [Line Items] |  |  |  |  |  |  |
Percentage of purchases during year |  |  |  |  | 11.00% |  |
Sales Revenue, Net [Member] | American Airlines Inc. [Member] | Customer Concentration Risk [Member] |  |  |  |  |  |  |
Concentration Risk [Line Items] |  |  |  |  |  |  |
Concentration risk, percentage |  |  |  |  | 0.00% | 23.00% | 45.00%
Sales Revenue, Net [Member] | United Airlines Inc [Member] | Customer Concentration Risk [Member] |  |  |  |  |  |  |
Concentration Risk [Line Items] |  |  |  |  |  |  |
Concentration risk, percentage | 98.00% | 98.00% | 98.00% | 96.00% | 97.00% | 73.00% | 48.00%

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