Estimated initial equity warrant asset value.

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Estimated initial warrant asset value.

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Grant date value for additional warrant to purchase shares.

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Initial investment in preferred stock measured at cost.

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Number of engines to be sold.

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Number of rotable parts on impairment true-up adjustment.

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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.

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

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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.

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

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

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Amount of realized gain 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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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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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).

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Amount of investment in equity security without readily determinable fair value.

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

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Balance Sheet Information - Additional Information (Detail)			1 Months Ended		3 Months Ended		6 Months Ended	9 Months Ended
	Jul. 01, 2024 USD ($) shares	Jan. 31, 2024 USD ($)	Sep. 30, 2021 USD ($) shares	Jul. 31, 2021 USD ($)	Jun. 30, 2024 USD ($) RotableParts Engine shares	Jun. 30, 2023 USD ($)	Mar. 31, 2024 Engine	Jun. 30, 2024 USD ($) Engine	Jun. 30, 2023 USD ($)	Sep. 30, 2023 USD ($)	Feb. 28, 2022 USD ($)	Feb. 28, 2021 USD ($)
Condensed Balance Sheet Statements Captions [Line Items]
Impairment true-up adjustment					$ 4,300,000
Number of engines held to sale \| Engine					13		66	64
Number of rotable parts \| RotableParts					737
Depreciation expense					$ 9,700,000	$ 15,300,000		$ 32,800,000	$ 46,900,000
Estimated initial equity warrant asset value												$ 16,400,000
Number of shares sold \| shares					760,000
Proceeds from sale					$ 2,700,000
Total net unrealized gain/(loss)					(2,000,000)	2,900,000		(6,100,000)	3,300,000
Estimated initial warrant asset value											$ 3,200,000
Investments in equity securities					300,000			300,000		$ 20,320,000
Total realized gain (loss) on equity securities					6,500,000	$ 0		6,500,000	$ 0
Aggregate carrying amount of investments in equity securities					5,700,000			5,700,000		20,300,000
Investments without readily determinable fair value					300,000			300,000		$ 8,800,000
United Capacity Purchase Agreement [Member]
Condensed Balance Sheet Statements Captions [Line Items]
Debt reduction		$ 12,600,000
Realized and unrealized gain (loss) on investment		$ 7,200,000
Engines Held For Sale [Member]
Condensed Balance Sheet Statements Captions [Line Items]
Impairment true-up adjustment					5,700,000
Rotable Parts [Member]
Condensed Balance Sheet Statements Captions [Line Items]
Impairment true-up adjustment					$ 2,200,000
Archer Aviation, Inc. [Member] \| Level 1 [Member]
Condensed Balance Sheet Statements Captions [Line Items]
Number of shares sold \| shares					800,000
Proceeds from sale					$ 2,700,000
Loss on sale					800,000
Realized and unrealized gain (loss) on investment					(1,700,000)			(2,700,000)
Investments in equity securities					5,300,000			5,300,000
VTOL Aircraft, XTI Aerospace, Inc [Member] \| Level 1 [Member]
Condensed Balance Sheet Statements Captions [Line Items]
Realized and unrealized gain (loss) on investment								(3,400,000)
Investments in equity securities					$ 100,000			$ 100,000
Heart Aerospace Incorporated [Member] \| Forward Purchase Contract [Member] \| Preferred Stock [Member]
Condensed Balance Sheet Statements Captions [Line Items]
Purchase of preferred stock				$ 5,000,000.0
Initial investment in preferred stock measured at cost				$ 5,000,000
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
Subsequent Event [Member] \| Archer Aviation, Inc. [Member]
Condensed Balance Sheet Statements Captions [Line Items]
Number of shares sold \| shares	1,500,000
Proceeds from sale	$ 6,900,000
Realized gain on sale of shares	$ 1,600,000
Subsequent Event [Member] \| Archer Aviation, Inc. [Member] \| Level 1 [Member]
Condensed Balance Sheet Statements Captions [Line Items]
Number of shares sold \| shares	1,500,000
Proceeds from sale	$ 6,900,000
Realized gain on sale of shares	$ 1,600,000