Commitments - Summary of Future Minimum Lease Payments, Operating and Finance Leases (Details) $ in Millions	Aug. 31, 2020 USD ($)
Schedule Of Future Minimum Lease Payments For Operating Leases And Finance Leases [Line Items]
2021 (remainder)	$ 1,909
2022	2,376
2023	2,128
2024	1,798
2025	1,559
Thereafter	8,299
Total lease payments	18,069
Less imputed interest	(2,858)
Present value of lease liability	15,211
Operating Leases
2021 (remainder)	1,861
2022	2,349
2023	2,103
2024	1,774
2025	1,535
Thereafter	7,593
Total lease payments	17,215
Less imputed interest	(2,477)
Present value of lease liability	14,738
Finance Leases
2021 (remainder)	48
2022	27
2023	25
2024	24
2025	24
Thereafter	706
Total lease payments	854
Less imputed interest	(381)
Present value of lease liability	473
Aircraft and Related Equipment [Member]
Operating Leases
2021 (remainder)	200
2022	229
2023	198
2024	102
2025	69
Thereafter	258
Total lease payments	1,056
Less imputed interest	(85)
Present value of lease liability	971
Facilities and Other [Member]
Operating Leases
2021 (remainder)	1,661
2022	2,120
2023	1,905
2024	1,672
2025	1,466
Thereafter	7,335
Total lease payments	16,159
Less imputed interest	(2,392)
Present value of lease liability	$ 13,767

Finance lease liability payments due after year four.

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

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

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

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Lessee operating lease and finance lease liability undiscounted excess amount.

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

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Operating lease and finance lease liability.

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

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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

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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).

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Amount of lessee's undiscounted obligation for lease payment for finance lease to be paid in remainder of current fiscal year.

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-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

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

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

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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 payments in excess of discounted obligation for lease payments for operating lease.

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