Leases - Schedule of Future Minimum Lease Payments, Operating Leases (Details) $ in Millions	May 31, 2019 USD ($)
Schedule of Future Minimum Operating Lease Payments [Line Items]
2020	$ 2,497
2021	2,263
2022	2,028
2023	1,779
2024	1,486
Thereafter	8,062
Total	18,115
Aircraft and Related Equipment [Member]
Schedule of Future Minimum Operating Lease Payments [Line Items]
2020	288
2021	230
2022	212
2023	154
2024	58
Thereafter	85
Total	1,027
Facilities and Other [Member]
Schedule of Future Minimum Operating Lease Payments [Line Items]
2020	2,209
2021	2,033
2022	1,816
2023	1,625
2024	1,428
Thereafter	7,977
Total	$ 17,088

Schedule of Future Minimum Operating Lease Payments [Line Items]

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Amount of required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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