Sale of Composites Business (Details) - Composites Business $ in Millions		3 Months Ended
Aug. 31, 2020 USD ($)	Aug. 31, 2020 USD ($)
Sale of Business
Loss on the sale of the composites business		$ 19.5
Disposal group, loss on sale of business, Income Statement location		us-gaap:IncomeLossFromDiscontinuedOperationsNetOfTax
Consideration from sale	$ 2.3	$ 2.3
Maximum contingent consideration	6.5	$ 6.5
Contingent consideration period for achievement of target sales		3 years
Cash consideration received	1.0
Fair value of earn-out consideration	$ 1.3	$ 1.3

Period to achieve sales targets which are required for contingent consideration for the sale of the business.

No definition available.

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- Definition

The fair value of earn-out consideration received from the sale of a portion of the company's business, for example a segment, division, branch or other business, during the period.

+ References

No definition available.

+ Details

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- Definition

The maximum amount of contingent consideration based on the achievement of sales targets over the expected years.

+ References

No definition available.

+ Details

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Namespace Prefix:	air_
Data Type:	xbrli:monetaryItemType
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- Definition

Amount of consideration received or receivable for the disposal of assets and liabilities, including discontinued operation.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount before tax of gain (loss) recognized on the sale or disposal of a disposal group. Excludes discontinued operations.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=109226348&loc=d3e2443-110228

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3602-108585

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=109226691&loc=d3e2941-110230

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Indicates line item in statement of income that includes gain (loss) recognized on sale or disposal of disposal group. Excludes discontinued operation.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=109226691&loc=d3e2941-110230

+ Details

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Data Type:	srt-types:extensibleListItemType
Balance Type:	na
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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

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
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- Definition

The cash inflow associated with the amount received from the sale of a portion of the company's business, for example a segment, division, branch or other business, during the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3179-108585

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

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