Sales (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	May 31, 2023	May 31, 2022	May 31, 2023	May 31, 2022
Disaggregation of Revenue [Line Items]
Sales	$ 35,415	$ 32,597	$ 103,659	$ 100,254
Reportable Segments | U.S. Retail Pharmacy
Disaggregation of Revenue [Line Items]
Sales	27,866	26,695	82,648	82,394
Reportable Segments | U.S. Retail Pharmacy | Pharmacy
Disaggregation of Revenue [Line Items]
Sales	20,898	19,656	60,991	60,581
Reportable Segments | U.S. Retail Pharmacy | Retail
Disaggregation of Revenue [Line Items]
Sales	6,968	7,039	21,657	21,814
Reportable Segments | International
Disaggregation of Revenue [Line Items]
Sales	5,573	5,305	16,414	16,686
Reportable Segments | International | Pharmacy
Disaggregation of Revenue [Line Items]
Sales	924	901	2,690	2,876
Reportable Segments | International | Retail
Disaggregation of Revenue [Line Items]
Sales	1,769	1,618	5,412	5,294
Reportable Segments | International | Wholesale
Disaggregation of Revenue [Line Items]
Sales	2,880	2,786	8,311	8,516
Reportable Segments | U.S. Healthcare
Disaggregation of Revenue [Line Items]
Sales	1,975	596	4,597	1,173
Corporate and Other
Disaggregation of Revenue [Line Items]
Sales	$ 0	$ 1	$ 0	$ 0