Number of aircraft classified as assets held for sale.

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
-Name Regulation S-X (SX)
-Number 210
-Section 12
-Subsection 04
-Paragraph a
-Publisher SEC

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
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-Name Accounting Standards Codification
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Reference 3: http://www.xbrl.org/2003/role/recommendedDisclosureRef
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-Name Accounting Standards Codification
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-Publisher FASB
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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

+ Details

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Period Type:	duration

- 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
-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 1A
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482736/825-10-45-1A

+ Details

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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 28
-Subparagraph (b)
-SubTopic 10
-Topic 230
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-Name Accounting Standards Codification
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-Publisher FASB
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- Details

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- Details

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- Details

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Balance Sheet Information - Additional Information (Detail)	3 Months Ended		6 Months Ended
	Mar. 31, 2025 USD ($) AirCraft Airframes	Mar. 31, 2024 USD ($)	Mar. 31, 2025 USD ($)	Mar. 31, 2024 USD ($)	Sep. 30, 2024 USD ($)
Condensed Balance Sheet Statements Captions [Line Items]
Impairment true-up adjustment	$ 12,400,000
Depreciation expense	6,000,000	$ 9,800,000	$ 13,900,000	$ 23,100,000
Investments in equity securities	$ 300,000		$ 300,000		$ 300,000
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
Engines Held For Sale [Member]
Condensed Balance Sheet Statements Captions [Line Items]
Impairment true-up adjustment	$ 33,800