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Debt - Narrative (Details) € in Millions					9 Months Ended
Debt - Narrative (Details) € in Millions	Apr. 26, 2021 USD ($)	Jan. 28, 2021 USD ($)	Dec. 23, 2020 USD ($)	Aug. 30, 2019 USD ($) credit_agreement	May 31, 2021 USD ($)	May 31, 2021 EUR (€)	May 31, 2020 USD ($)	Apr. 23, 2021 USD ($)	Apr. 09, 2021 USD ($)	May 29, 2020 USD ($)	Apr. 15, 2020 USD ($)	Apr. 07, 2020 USD ($)	Apr. 02, 2020 USD ($)	Apr. 01, 2020 USD ($)	Jan. 18, 2019 USD ($)	Dec. 05, 2018 USD ($)	Nov. 30, 2018 USD ($)	Aug. 29, 2018 USD ($)
Debt Instrument [Line Items]
Interest paid					$ 889,000,000		$ 510,000,000
Loss on early extinguishment of debt					$ 419,000,000		0
Maximum
Debt Instrument [Line Items]
Debt to total capitalization ratio					0.60
Commercial paper
Debt Instrument [Line Items]
Average daily short-term borrowings					$ 2,300,000,000		$ 2,600,000,000
Weighted average interest rate					0.47%	0.47%	2.33%
Commercial paper \| Guarantor Subsidiaries \| Reportable Legal Entities
Debt Instrument [Line Items]
Average daily short-term borrowings					$ 424,000,000	€ 300
Weighted average interest rate					0.43%	0.43%
Total $1.5 billion note issuance
Debt Instrument [Line Items]
Face amount											$ 1,500,000,000
Debt issuance costs											13,000,000
Unsecured Notes
Debt Instrument [Line Items]
Loss on early extinguishment of debt	$ 419,000,000				$ 387,000,000
Unsecured Notes \| Total $1.5 billion note issuance
Debt Instrument [Line Items]
Face amount					$ 1,500,000,000
Unsecured Notes \| 3.200% unsecured notes due 2030
Debt Instrument [Line Items]
Face amount											$ 500,000,000
Stated interest rate					3.20%						3.20%
Unsecured Notes \| 4.100% unsecured notes due 2050
Debt Instrument [Line Items]
Face amount											$ 1,000,000,000.0
Stated interest rate					4.10%						4.10%
Debt redeemed	$ 200,000,000
Unsecured Notes \| December 2018 Term Loan Credit Agreement
Debt Instrument [Line Items]
Face amount																$ 1,000,000,000.0
Credit facilities \| 2020 Revolving Credit Agreement, 364-Day Facility
Debt Instrument [Line Items]
Maximum borrowing capacity			$ 1,250,000,000
Credit facilities \| 2020 Revolving Credit Agreement, 18-Month Revolving Credit Facility
Debt Instrument [Line Items]
Maximum borrowing capacity			$ 2,250,000,000
Debt term			18 months
Borrowing outstanding					$ 400,000,000
Credit facilities \| April 7, 2020 Revolving Credit Agreement
Debt Instrument [Line Items]
Maximum borrowing capacity												$ 500,000,000
Credit facilities \| April 2020 Revolving Bilateral Credit Agreement
Debt Instrument [Line Items]
Maximum borrowing capacity														$ 750,000,000
Credit facilities \| April 2020 Revolving Club Credit Agreement
Debt Instrument [Line Items]
Maximum borrowing capacity													$ 1,325,000,000
Credit facilities \| August 2019 Revolving Credit Agreements
Debt Instrument [Line Items]
Maximum borrowing capacity				$ 500,000,000
Debt term				18 months
Number of credit agreements \| credit_agreement				3
Credit facilities \| January 2019 364-Day Revolving Credit Agreement
Debt Instrument [Line Items]
Maximum borrowing capacity			$ 500,000,000												$ 2,000,000,000.0
Credit facility, amount terminated		$ 1,500,000,000
Credit facilities \| A&R December 2018 Credit Agreement
Debt Instrument [Line Items]
Face amount													2,000,000,000.0
Credit facilities \| November 2018 Credit Agreement
Debt Instrument [Line Items]
Maximum borrowing capacity																	$ 1,000,000,000.0
Credit facilities \| August 2018 Revolving Credit Agreement
Debt Instrument [Line Items]
Face amount																		$ 3,500,000,000
Credit facilities \| Unsecured Notes \| A&R December 2018 Credit Agreement
Debt Instrument [Line Items]
Face amount													$ 1,000,000,000.0
Credit facilities \| Line of Credit \| November 2018 Credit Agreement
Debt Instrument [Line Items]
Maximum borrowing capacity										$ 500,000,000							500,000,000
Credit facilities \| Term Loan \| April 2021 Credit Agreement
Debt Instrument [Line Items]
Maximum borrowing capacity								$ 3,800,000,000	$ 2,750,000,000
Borrowing outstanding					$ 3,800,000,000
Credit facilities \| Term Loan \| November 2018 Credit Agreement
Debt Instrument [Line Items]
Maximum borrowing capacity										$ 1,000,000,000.0							$ 500,000,000
Bridge Loan \| 2020 Revolving Credit Agreement, 18-Month Revolving Credit Facility
Debt Instrument [Line Items]
Maximum borrowing capacity			$ 350,000,000
Letter of Credit \| August 2018 Revolving Credit Agreement
Debt Instrument [Line Items]
Face amount																		$ 500,000,000