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Organization and Operations - Additional Information (Detail) $ in Thousands				1 Months Ended		3 Months Ended	7 Months Ended
	Jan. 11, 2024 USD ($) AirCraft	Jan. 01, 2024 USD ($) Engine	Dec. 01, 2023 Engine	Jan. 31, 2024 AirCraft	Dec. 31, 2023 USD ($) DailyDeparture AirCraft State	Dec. 31, 2023 USD ($) DailyDeparture AirCraft State Engine Employee City	Apr. 30, 2024 USD ($)
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Number of states in which entity operates \| State					36	36
Additional payments received related to block hour rate increase						$ 8,800
Number of aircrafts operated \| AirCraft						80
Number of cities in which entity operates \| City						82
Number of daily departures \| DailyDeparture					280	280
Number of employees \| Employee						2,246
Long-term debt					$ 156,800	$ 156,800
Number of surplus engines to be sold \| Engine			12
Loan forgiven						2,954
Reduction in loan amount						$ 5,000
Number of engines held to sale \| Engine						48
Purchase agreement [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Gross proceeds from sale of asset						$ 11,500
Number of engines held to sale \| Engine						23
Impact of Pilot Shortage and Transition of Operations to United [Member] \| Export Development Bank of Canada Agreement [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Principal contingent amount upon repayment						$ 4,200
Impact of Pilot Shortage and Transition of Operations to United [Member] \| RASPRO Aircraft Lease Agreement [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Number of aircrafts operated \| AirCraft						15
Subsequent Event [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Additional payments received related to block hour rate increase							$ 21,300
Number of aircraft sold	4	12
Gross proceeds from sale of asset		$ 54,200
Proceeds from sale of asset		15,900
Subsequent Event [Member] \| Minimum [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Additional revenue and liquidity	$ 20,400
Subsequent Event [Member] \| Maximum [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Additional revenue and liquidity	26,800
Revolving Credit Facility [Member] \| Subsequent Event [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Repayments of long term debt	2,100
United [Member] \| Subsequent Event [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Repayments of long term debt	10,500
United Capacity Purchase Agreement [Member] \| Maximum [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Number of aircrafts operated \| AirCraft						80
United Capacity Purchase Agreement [Member] \| Subsequent Event [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Realized and unrealized gain on investment		$ 7,200
Repayments of long term debt	10,500
United Capacity Purchase Agreement [Member] \| Subsequent Event [Member] \| Minimum [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Additional revenue and liquidity	20,400
United Capacity Purchase Agreement [Member] \| Subsequent Event [Member] \| Maximum [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Additional revenue and liquidity	$ 26,800
CRJ-900 Aircraft [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Number of aircraft sold \| AirCraft						4
Number of aircraft to be sold \| AirCraft						11
Gross proceeds from sale of asset						$ 12,000
CRJ-900 Aircraft [Member] \| Edc Loan And Mhirj Junior Note
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Repayments of long term debt						4,200
Proceeds from sale of asset						600
Loan forgiven						$ 5,000
CRJ-900 Aircraft [Member] \| American Airlines Inc [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Number of aircraft sold \| AirCraft						4
Gross proceeds from sale of asset						$ 41,500
Proceeds from sale of asset						$ 5,700
CRJ-900 Aircraft [Member] \| American Airlines Inc [Member] \| Export Development Bank of Canada Agreement [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Number of aircraft sold \| AirCraft						7
CRJ-900 Aircraft [Member] \| United Capacity Purchase Agreement [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Number of aircrafts operated \| AirCraft					26	26
Maximum number of aircraft to be operated \| AirCraft						38
CRJ-900 Aircraft [Member] \| United Capacity Purchase Agreement [Member] \| Subsequent Event [Member] \| Maximum [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Number of aircrafts operated \| AirCraft				8
E-175 Aircraft [Member] \| United Capacity Purchase Agreement [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Number of aircrafts operated \| AirCraft						54
E-175 Aircraft [Member] \| United Capacity Purchase Agreement [Member] \| United [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Number of aircrafts operated \| AirCraft						42
Number of aircrafts owned \| AirCraft						18
Lease expiration year						2028
Notice period for termination of agreement						United, subject to certain conditions, including the payment of certain costs tied to aircraft type, to terminate the agreement in its discretion, or remove aircraft from service, by giving us notice of 90 days or more
E-175 Aircraft [Member] \| United Capacity Purchase Agreement [Member] \| United [Member] \| Minimum [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Lease expiration year						2024
E-175 Aircraft [Member] \| United Capacity Purchase Agreement [Member] \| United [Member] \| Maximum [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Lease expiration year						2028
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
UST Loan [Member] \| CRJ-900 Aircraft [Member]
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Number of aircraft sold \| AirCraft						4
Gross proceeds from sale of asset						$ 12,000
Proceeds from sale of asset						$ 6,500