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Debt - narrative (Details) £ in Millions						12 Months Ended
Debt - narrative (Details) £ in Millions	Jun. 17, 2022 USD ($)	Nov. 17, 2021 USD ($)	Nov. 15, 2021 USD ($)	Apr. 26, 2021 USD ($)	Dec. 23, 2020 USD ($)	Aug. 31, 2022 USD ($)	Aug. 31, 2021 USD ($)	Aug. 31, 2021 GBP (£)	Aug. 31, 2020 USD ($)	Aug. 29, 2018 USD ($)
Line of Credit Facility [Line Items]
Interest paid, net of capitalized interest						$ 420,000,000	$ 916,000,000		$ 584,000,000
Loss on early extinguishment of debt						6,000,000	414,000,000		0
Commercial paper
Line of Credit Facility [Line Items]
Average daily short-term borrowings						$ 910,000,000	$ 1,900,000,000		$ 2,500,000,000
Weighted-average interest rate						0.55%	0.45%		2.15%
Commercial paper, amount outstanding						$ 0	$ 0
Commercial paper \| Guarantor Subsidiaries \| Reportable Legal Entities
Line of Credit Facility [Line Items]
Average daily short-term borrowings							$ 424,000,000	£ 300
Weighted-average interest rate for subsidiaries borrowings							0.43%	0.43%
Maximum
Line of Credit Facility [Line Items]
Debt to total capitalization ratio						0.60
Unsecured notes
Line of Credit Facility [Line Items]
Loss on early extinguishment of debt				$ 414,000,000		$ 6,000,000	$ 387,000,000
Unsecured notes \| 0.9500% notes payable, due 2023
Line of Credit Facility [Line Items]
Face amount		$ 850,000,000				$ 850,000,000
Stated interest rate (as a percent)		95.00%				0.95%
Debt instrument, redemption price, percentage		100.00%
Long term debt						$ 848,000,000	$ 0
Credit facilities \| Term loan \| Eurodollar
Line of Credit Facility [Line Items]
Debt instrument, basis spread on variable rate			0.70%
Credit facilities \| June 17, 2022 revolving credit facility, five-year facility
Line of Credit Facility [Line Items]
Face amount	$ 3,500,000,000
Debt term	5 years
Credit facilities \| June 17, 2022 revolving credit facility, 18-month facility
Line of Credit Facility [Line Items]
Face amount	$ 1,500,000,000
Debt term	18 months
Borrowings outstanding						0
Credit facilities \| June 17, 2022 revolving credit facility, 18-month facility \| Maximum
Line of Credit Facility [Line Items]
Debt instrument, basis spread on variable rate	1.50%
Credit facilities \| June 17, 2022 revolving credit facility, 18-month facility \| Minimum
Line of Credit Facility [Line Items]
Debt instrument, basis spread on variable rate	0.80%
Credit facilities \| Delayed draw term loan credit facility
Line of Credit Facility [Line Items]
Face amount			$ 5,000,000,000
Credit facilities \| Delayed draw term loan credit facility \| Term loan
Line of Credit Facility [Line Items]
Long term debt						$ 4,000,000,000
Credit facilities \| Delayed draw term loan credit facility, 364-day facility \| Term loan
Line of Credit Facility [Line Items]
Face amount			$ 2,000,000,000
Debt term			364 days
Credit facilities \| Delayed draw term loan credit facility, 364-day facility \| Term loan \| Eurodollar
Line of Credit Facility [Line Items]
Debt instrument, basis spread on variable rate			0.75%
Credit facilities \| Delayed draw term loan credit facility, 364-day facility \| Term loan \| Base Rate
Line of Credit Facility [Line Items]
Debt instrument, basis spread on variable rate			0.00%
Credit facilities \| Delayed draw term loan credit facility, two-year facility \| Term loan
Line of Credit Facility [Line Items]
Debt term			2 years
Credit facilities \| Delayed draw term loan credit facility, 364-day facility, tranche two \| Term loan \| Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate
Line of Credit Facility [Line Items]
Debt instrument, basis spread on variable rate			0.00%
Credit facilities \| December 23, 2020 revolving credit agreement, 364-day facility
Line of Credit Facility [Line Items]
Debt term					364 days
Maximum borrowing capacity					$ 1,250,000,000
Credit facilities \| December 23, 2020 revolving credit agreement, 18-month revolving credit facility
Line of Credit Facility [Line Items]
Debt term					18 months
Maximum borrowing capacity					$ 2,250,000,000
Credit facilities \| August 2018 Revolving Credit Agreement
Line of Credit Facility [Line Items]
Face amount										$ 3,500,000,000
Credit facilities \| Term loan
Line of Credit Facility [Line Items]
Face amount			$ 3,000,000,000
Credit facilities \| Term loan \| June 17, 2022 revolving credit facility, five-year facility
Line of Credit Facility [Line Items]
Debt term	5 years
Credit facilities \| Term loan \| June 17, 2022 revolving credit facility, 18-month facility
Line of Credit Facility [Line Items]
Debt term	18 months
Credit facilities \| Term loan \| Delayed draw term loan credit facility, two-year facility
Line of Credit Facility [Line Items]
Face amount			$ 2,000,000,000
Debt term			2 years
Credit facilities \| Term loan \| Delayed draw term loan credit facility, two-year facility \| Eurodollar
Line of Credit Facility [Line Items]
Debt instrument, basis spread on variable rate			0.85%
Credit facilities \| Term loan \| Delayed draw term loan credit facility, two-year facility \| Base Rate
Line of Credit Facility [Line Items]
Debt instrument, basis spread on variable rate			0.00%
Credit facilities \| Term loan \| Delayed draw term loan credit facility, three-year facility
Line of Credit Facility [Line Items]
Face amount			$ 1,000,000,000
Debt term			3 years
Credit facilities \| Term loan \| Delayed draw term loan credit facility, three-year facility \| Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate
Line of Credit Facility [Line Items]
Debt instrument, basis spread on variable rate			1.00%
Letter of Credit \| August 2018 Revolving Credit Agreement
Line of Credit Facility [Line Items]
Face amount										$ 500,000,000
Bridge Loan \| December 23, 2020 revolving credit agreement, 18-month revolving credit facility
Line of Credit Facility [Line Items]
Maximum borrowing capacity					$ 350,000,000