Summary of Significant Accounting Policies - Rotable Assets and Equipment under Leases (Details)	12 Months Ended
May 31, 2020
Minimum
Rotable Assets and Equipment under leases
Period of short-term leases	1 month
Maximum
Rotable Assets and Equipment under leases
Period of short-term leases	12 months

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.

No definition available.

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