Organization Consolidation And Presentation Of Financial Statements [Line Items]

$ 1,000

$ 20,313

$ 36,641

$ 40,814

Organization Consolidation And Presentation Of Financial Statements [Line Items]

Notice period for termination of agreement

United, subject to certain conditions, including the payment of certain costs tied to aircraft type, may terminate the agreement in its discretion, or remove E-175 aircraft from service, by giving us notice of 90 days or more

Organization and Operations - Additional Information 1 (Detail) $ in Thousands		12 Months Ended
	Dec. 20, 2019 AirCraft	Sep. 30, 2024 USD ($) AirCraft	Sep. 30, 2023 USD ($)	Sep. 30, 2022 USD ($)	Mar. 15, 2024 USD ($)
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Number of aircrafts operated \| AirCraft		67
Wind-down and associated cost \| $					$ 1,000
United capacity purchase agreement termination notice period		30 days
Purcahse of aircraft \| $		$ 20,313	$ 36,641	$ 40,814
Boeing 737400F [Member] \| DHL Flight Services Agreement [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Number of aircrafts operated \| AirCraft	4
E175LL Aircraft [Member] \| United Capacity Purchase Agreement [Member] \| United [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Notice period for termination of agreement		United, subject to certain conditions, including the payment of certain costs tied to aircraft type, may terminate the agreement in its discretion, or remove E-175 aircraft from service, by giving us notice of 90 days or more