Estimated initial equity warrant asset value.

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- Definition

Estimated initial warrant asset value.

+ References

No definition available.

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- Definition

Grant date value for additional warrant to purchase shares.

+ References

No definition available.

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- Definition

Initial investment in preferred stock measured at cost.

+ References

No definition available.

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- Definition

Number of aircraft classified as assets held for sale.

+ References

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

Decrease for amounts of indebtedness forgiven by the holder of the debt instrument.

+ References

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

The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

+ References

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- Definition

This element represents the aggregate cost of investments accounted for under the equity method of accounting.

+ References

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- Definition

Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI), classified as noncurrent.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

Amount of realized gain (loss) from sale of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

Amount of unrealized gain (loss) on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Amount of investment in equity security without readily determinable fair value.

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- Definition

Amount of realized and unrealized gain (loss) on investment.

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Amount of gain (loss) from the difference between the sale price or salvage price and the book value of an asset that was sold or retired, and gain (loss) from the write down of assets from their carrying value to fair value.

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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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- Definition

Number of shares of stock issued during the period pursuant to acquisitions.

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Value of stock issued pursuant to acquisitions during the period.

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Value of shares of stock issued during the period as part of a transaction to acquire assets that do not qualify as a business combination.

+ References

No definition available.

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Balance Sheet Information - Additional Information (Detail)	1 Months Ended		3 Months Ended		6 Months Ended		12 Months Ended
	Sep. 30, 2021 USD ($) shares	Jul. 31, 2021 USD ($)	Mar. 31, 2025 USD ($) AIRFRAMES AIRCRAFT	Mar. 31, 2024 USD ($)	Mar. 31, 2025 USD ($)	Mar. 31, 2024 USD ($)	Sep. 30, 2024 USD ($)	Sep. 30, 2023 USD ($)	Sep. 30, 2022 USD ($)	Feb. 28, 2022 USD ($)	Feb. 28, 2021 USD ($)
Condensed Balance Sheet Statements Captions [Line Items]
Depreciation expense			$ 6,000,000	$ 9,800,000	$ 13,900,000	$ 23,100,000	$ 40,000,000	$ 60,200,000	$ 80,500,000
Estimated initial equity warrant asset value											$ 16,400,000
Investments in equity securities			300,000		$ 300,000		300,000	20,320,000
Total net unrealized gain/(loss)							(6,100)	5,400,000
Estimated initial warrant asset value										$ 3,200,000
Total realized gain (loss) on equity securities							8,000,000	0
Aggregate carrying amount of investments in equity securities							300,000	20,300,000
Investments without readily determinable fair value							300,000	8,800,000
Impairment true-up adjustment			12,400,000				73,700,000	50,600,000	$ 62,100,000
United Capacity Purchase Agreement [Member]
Condensed Balance Sheet Statements Captions [Line Items]
Realized and unrealized gain (loss) on investment							7,200,000
Debt reduction							12,600,000
Engines Held For Sale [Member]
Condensed Balance Sheet Statements Captions [Line Items]
Impairment true-up adjustment			$ 33,800
Archer Aviation, Inc. [Member] \| Level 1 [Member]
Condensed Balance Sheet Statements Captions [Line Items]
Proceeds from sale							9,600,000
Loss on sale							800,000
Realized and unrealized gain (loss) on investment							(2,700,000)	$ 5,600,000
Heart Aerospace Incorporated [Member] \| Forward Purchase Contract [Member] \| Preferred Stock [Member]
Condensed Balance Sheet Statements Captions [Line Items]
Purchase of preferred stock		$ 5,000,000
Initial investment in preferred stock measured at cost		$ 5,000,000
VTOL Aircraft, XTI Aerospace, Inc [Member] \| Level 1 [Member]
Condensed Balance Sheet Statements Captions [Line Items]
Realized and unrealized gain (loss) on investment							(3,500,000)
Investments in equity securities							$ 100,000
Class A [Member] \| Archer Aviation, Inc. [Member]
Condensed Balance Sheet Statements Captions [Line Items]
Number of shares sold \| shares	500,000
Proceeds from sale	$ 5,000,000
Total grant date value, Additional warrant to purchase shares	$ 5,600,000
C R J 900 Airframes [Member]
Condensed Balance Sheet Statements Captions [Line Items]
Number of aircraft classified as assets held for sale \| AIRFRAMES			3
CF34-8C Engines [Member]
Condensed Balance Sheet Statements Captions [Line Items]
Number of aircraft classified as assets held for sale \| AIRCRAFT			4