Revenue Recognition (Details) - USD ($) $ in Millions	3 Months Ended
Aug. 31, 2021	Aug. 31, 2020
Revenue Recognition
Unfavorable cumulative catch-up adjustments	$ (1.0)
Favorable cumulative catch-up adjustments		$ 0.3
Practical Expedient, Incremental costs of obtaining a contract	true
Practical Expedient, Remaining performance obligations	true

Amount of increase in revenue recognized for cumulative catch-up adjustment from change in measure of progress which increases right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time.

No definition available.

+ Details

Name:	air_ContractWithCustomerAssetCumulativeCatchUpFavorableAdjustmentToRevenueChangeInMeasureOfProgress
Namespace Prefix:	air_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of decrease in revenue recognized for cumulative catch-up adjustment from change in measure of progress which decreases right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time.

+ References

No definition available.

+ Details

Name:	air_ContractWithCustomerAssetCumulativeCatchUpUnfavorableAdjustmentToRevenueChangeInMeasureOfProgress
Namespace Prefix:	air_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- References

No definition available.

+ Details

Name:	us-gaap_RevenueFromContractWithCustomerAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Indicates (true false) whether practical expedient was elected to recognize incremental cost of obtaining contract as expense when incurred if amortization period would have been one year or less.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 340
-SubTopic 40
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=68051541&loc=SL51790836-203054

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 22
-URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130569-203045

+ Details

Name:	us-gaap_RevenuePracticalExpedientIncrementalCostOfObtainingContract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:booleanItemType
Balance Type:	na
Period Type:	duration

- Definition

Indicates (true false) whether practical expedient was elected not to disclose amount of transaction price allocated to remaining performance obligation and explanation of expected timing of revenue recognition for reporting period presented prior to date of initial application under retrospective method.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 65
-Paragraph 1
-Subparagraph (f)(3)
-URI http://asc.fasb.org/extlink&oid=113356391&loc=SL49131195-203048

+ Details

Name:	us-gaap_RevenuePracticalExpedientInitialApplicationAndTransitionNondisclosureOfTransactionPriceAllocationToRemainingPerformanceObligation
Namespace Prefix:	us-gaap_
Data Type:	xbrli:booleanItemType
Balance Type:	na
Period Type:	duration