Common stock issued equivalent percentage of issued and outstanding capital stock.

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- Definition

Expected gross proceeds from sale of productive assets.

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No definition available.

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- Definition

Expected proceeds from sale of productive assets.

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- Definition

Gross Proceeds From Sale Of Productive Assets

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No definition available.

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- Definition

Impairment loss held for sale.

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No definition available.

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- Definition

Loan balance forgiven.

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No definition available.

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- Definition

Minimum collateral coverage ratio 1.

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No definition available.

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- Definition

Number of aircraft classified as assets held for sale.

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No definition available.

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- Definition

Number of aircraft sold.

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No definition available.

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- Definition

Number of engine sold.

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No definition available.

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- Definition

Number of engines to be sold.

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No definition available.

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- Definition

Percentage of increase in CPA block hour rates.

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No definition available.

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- Definition

Remaining balance

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No definition available.

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- Definition

The aggregate amount of write-downs for impairments recognized during the period for long-lived assets held for abandonment, exchange or sale.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
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- Definition

The cash inflow from the sale of property, plant and equipment (capital expenditures), software, and other intangible assets.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

The cash inflow from the sale of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale.

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- Definition

Amount of cash outflow for short-term and long-term debt. Excludes payment of lease obligation.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Subsequent Events - Additional Information (Detail) $ in Millions									1 Months Ended	3 Months Ended	9 Months Ended	12 Months Ended
	Jul. 24, 2025 USD ($) ENGINE	Apr. 04, 2025	Apr. 03, 2025 USD ($) AIRFRAMES AIRCRAFT ENGINE	Mar. 18, 2025	Dec. 31, 2024 USD ($) AIRCRAFT	Dec. 24, 2024 USD ($) AIRFRAMES	Dec. 23, 2024 USD ($)	Oct. 01, 2024 USD ($) AIRCRAFT AIRFRAMES	Dec. 31, 2015 USD ($)	Jun. 30, 2025 USD ($)	Jun. 30, 2025 AIRCRAFT	Sep. 30, 2024 USD ($) ENGINE	Sep. 30, 2023 USD ($)	Sep. 30, 2022 USD ($)	Dec. 30, 2024 USD ($)
Subsequent Event [Line Items]
Number of engines to be sold \| ENGINE												55
Impairment loss										$ 0.1		$ 73.7	$ 50.6	$ 62.1
E-175 Aircraft [Member]
Subsequent Event [Line Items]
Number of aircraft sold \| AIRCRAFT											18
Remaining balance									$ 73.4
CRJ-700 Aircraft [Member]
Subsequent Event [Line Items]
Number of aircraft sold \| AIRCRAFT								2
UST Loan [Member] \| Minimum [Member]
Subsequent Event [Line Items]
Minimum collateral coverage ratio				0.91			0.99
Subsequent Event [Member]
Subsequent Event [Line Items]
Percentage of increase in CPA block hour rates		3.00%
Number of engines to be sold \| ENGINE			23
Remaining balance								$ 73.4
Proceeds from Sale of Property, Plant, and Equipment	$ 4.6
Subsequent Event [Member] \| United Capacity Purchase Agreement [Member] \| United Airlines Inc [Member]
Subsequent Event [Line Items]
Common stock issued equivalent percentage of issued and outstanding capital stock		6.00%
Subsequent Event [Member] \| Engines Held For Sale [Member]
Subsequent Event [Line Items]
Impairment Loss Held For Sale			$ 14.7					$ 25.4
Subsequent Event [Member] \| United Revolving Credit Facility [Member]
Subsequent Event [Line Items]
Loan balance forgiven															$ 4.5
Subsequent Event [Member] \| E-175 Aircraft [Member]
Subsequent Event [Line Items]
Number of aircraft sold \| AIRCRAFT								2
Subsequent Event [Member] \| E-175 Aircraft [Member] \| Aircraft Purchase Agreement [Member]
Subsequent Event [Line Items]
Expected gross proceeds from sale of asset					$ 227.7
Expected proceeds from sale of asset					$ 84.7
Number of aircraft classified as assets held for sale \| AIRCRAFT								18
Number of aircraft sold \| AIRCRAFT					18
Subsequent Event [Member] \| E-175 Aircraft [Member] \| United Aircraft Purchase Agreement [Member]
Subsequent Event [Line Items]
Expected gross proceeds from sale of asset								$ 84.7				$ 227.7
Expected proceeds from sale of asset			$ 16.3
Number of aircraft classified as assets held for sale \| AIRCRAFT					18			18
Gross proceeds from sale of asset								$ 120.6
Number of aircraft sold \| AIRCRAFT			23
Subsequent Event [Member] \| C R J 900 Airframes [Member] \| Aircraft Purchase Agreement [Member]
Subsequent Event [Line Items]
Number of aircraft sold \| AIRFRAMES								4
Subsequent Event [Member] \| C R J 900 Airframes [Member] \| Airframe Purchase Agreement [Member]
Subsequent Event [Line Items]
Number of aircraft classified as assets held for sale \| AIRFRAMES						29
Gross proceeds from sale of asset			$ 9.1				$ 19.0
Number of aircraft sold \| AIRFRAMES			14			15
Impairment loss						$ 6.7
Subsequent Event [Member] \| CRJ-700 Aircraft [Member]
Subsequent Event [Line Items]
Gross proceeds from sale of asset								$ 11.0
Net proceeds from sale of asset								$ 6.8
Subsequent Event [Member] \| CF34-8C Engines [Member] \| Airframe Purchase Agreement [Member]
Subsequent Event [Line Items]
Number of aircraft sold \| AIRFRAMES								18
Subsequent Event [Member] \| UST Loan [Member]
Subsequent Event [Line Items]
Minimum collateral coverage ratio							1.55
Number of engine sold \| ENGINE	5
Subsequent Event [Member] \| UST Loan [Member] \| Minimum [Member]
Subsequent Event [Line Items]
Minimum collateral coverage ratio				0.91			0.99
Subsequent Event [Member] \| UST Loan [Member] \| Aircraft Purchase Agreement [Member]
Subsequent Event [Line Items]
Gross proceeds from sale of asset								$ 22.4
Repayments of debt								$ 21.0
Subsequent Event [Member] \| UST Loan [Member] \| C R J 900 Airframes [Member] \| Airframe Purchase Agreement [Member]
Subsequent Event [Line Items]
Gross proceeds from sale of asset			$ 28.1