Leases - Summary of Future Minimum Lease Payments, Operating and Finance Leases (Details) - USD ($) $ in Millions	May 31, 2021	May 31, 2020
Schedule Of Future Minimum Lease Payments For Operating Leases And Finance Leases [Line Items]
2022	$ 2,656
2023	2,559
2024	2,112
2025	1,832
2026	1,600
Thereafter	8,240
Total lease payments	18,999
Less imputed interest	(2,891)
Present value of lease liability	16,108
Operating Leases
2022	2,637
2023	2,453
2024	2,088
2025	1,808
2026	1,577
Thereafter	7,542
Total lease payments	18,105
Less imputed interest	(2,522)
Present value of lease liability	15,583	$ 14,118
Finance Leases
2022	19
2023	106
2024	24
2025	24
2026	23
Thereafter	698
Total lease payments	894
Less imputed interest	(369)
Present value of lease liability	525	$ 485
Aircraft and Related Equipment [Member]
Operating Leases
2022	234
2023	198
2024	102
2025	69
2026	61
Thereafter	184
Total lease payments	848
Less imputed interest	(66)
Present value of lease liability	782
Facilities and Other [Member]
Operating Leases
2022	2,403
2023	2,255
2024	1,986
2025	1,739
2026	1,516
Thereafter	7,358
Total lease payments	17,257
Less imputed interest	(2,456)
Present value of lease liability	$ 14,801

Lessee operating lease and finance lease liability payments due.

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- Definition

Lessee operating lease and finance lease liability payments due after year five.

+ References

No definition available.

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- Definition

Lessee operating lease and finance lease liability payments due due next twelve months.

+ References

No definition available.

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- Definition

Lessee operating lease and finance lease liability payments due year five.

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- Definition

Lessee operating lease and finance lease liability payments due year four.

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- Definition

Lessee operating lease and finance lease liability payments due year two.

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- Definition

Lessee operating lease and finance lease liability undiscounted excess amount.

+ References

No definition available.

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- Definition

Lessee operating lease and finance lease liability payments due year three.

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- Definition

Operating lease and finance lease liability.

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No definition available.

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Schedule of future minimum lease payments for operating leases and finance leases.

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- Definition

Present value of lessee's discounted obligation for lease payments from finance lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=121609121&loc=SL77918701-209980

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121603541&loc=SL77918627-209977

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- Definition

Amount of lessee's undiscounted obligation for lease payments for finance lease.

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- Definition

Amount of lessee's undiscounted obligation for lease payment for finance lease to be paid after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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- Definition

Amount of lessee's undiscounted obligation for lease payment for finance lease to be paid in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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- Definition

Amount of lessee's undiscounted obligation for lease payment for finance lease to be paid in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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- Definition

Amount of lessee's undiscounted obligation for lease payment for finance lease to be paid in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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- Definition

Amount of lessee's undiscounted obligation for lease payment for finance lease to be paid in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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- Definition

Amount of lessee's undiscounted obligation for lease payment for finance lease to be paid in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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- Definition

Amount of lessee's undiscounted obligation for lease payments in excess of discounted obligation for lease payments for finance lease.

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- Definition

Amount of lessee's undiscounted obligation for lease payment for operating lease.

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- Definition

Amount of lessee's undiscounted obligation for lease payment for operating lease due after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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- Definition

Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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- Definition

Amount of lessee's undiscounted obligation for lease payments in excess of discounted obligation for lease payments for operating lease.

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Present value of lessee's discounted obligation for lease payments from operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121603541&loc=SL77918627-209977

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