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v3.25.2

Long-Term Debt, Finance Leases, and Other Borrowings - Schedule of Long-term Debt (Detail) - USD ($) $ in Thousands | Jun. 30, 2025 | Sep. 30, 2024
--- | --- | ---
Debt Instrument [Line Items] |  |
Gross long-term debt, including current maturities | $ 113,744 | $ 315,210
Less unamortized debt issuance costs |  | (2,395)
Less notes payable warrants | (774) | (2,544)
Net long-term debt, including current maturities | 112,970 | 310,271
Less current portion, net of unamortized debt issuance costs | (84,725) | (50,455)
Net long-term debt | 28,245 | 259,816
Revolving Credit Facility, Quarterly Interest Through 2028 [Member] |  |
Debt Instrument [Line Items] |  |
Gross long-term debt, including current maturities | 33,018 | 37,520
Notes Payable to Secured Parties, Due in Semi Annual Installments Collateralized by the Underlying Aircraft Through 2028 [Member] |  |
Debt Instrument [Line Items] |  |
Gross long-term debt, including current maturities |  | 85,469
Notes Payable to Secured Parties, Due in Quarterly Installments Collateralized by the Underlying Aircraft Through 2028 [Member] |  |
Debt Instrument [Line Items] |  |
Gross long-term debt, including current maturities |  | 73,884
Other Obligations Due to Financial Institutions, Monthly or Quarterly Collateralized by the Underlying Equipment, Due 2022 Through 2031 [Member] |  |
Debt Instrument [Line Items] |  |
Gross long-term debt, including current maturities |  | 4,681
Notes Payable to the UST, Quarterly Through 2025 [Member] |  |
Debt Instrument [Line Items] |  |
Gross long-term debt, including current maturities | $ 80,726 | $ 113,656

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