Commitments - Additional Information (Details) $ in Millions	3 Months Ended
	Aug. 31, 2021 USD ($) air-craft
Other Aircraft Commitments Disclosure [Abstract]
Deposit and Progress Payments \| $	$ 769
Lessee Disclosure [Abstract]
Additional leases not yet commenced, undiscounted future payments \| $	$ 2,600
Minimum [Member]
Lessee Disclosure [Abstract]
Operating lease commencement date	2022
Maximum [Member]
Lessee Disclosure [Abstract]
Operating lease commencement date	2023
B777F [Member]
Other Aircraft Commitments Disclosure [Abstract]
Conditional Aircraft Commitments	3
B767F [Member]
Other Aircraft Commitments Disclosure [Abstract]
Conditional Aircraft Commitments	2
Number of additional aircraft agreed to purchase options exercised	20
B767F Aircraft Delivered in 2025 [Member]
Other Aircraft Commitments Disclosure [Abstract]
Number of aircrafts rescheduled delivery	10
Aircraft expected to be delivered, latest fiscal year	2025
B767F Aircraft Delivered in 2024 [Member]
Other Aircraft Commitments Disclosure [Abstract]
Number of aircrafts rescheduled delivery	10
Aircraft expected to be delivered, earliest fiscal year	2024