Supplemental information - Narrative (Details) - USD ($) shares in Millions, $ in Millions	3 Months Ended
	Nov. 30, 2024	Nov. 30, 2023	Aug. 31, 2024	Aug. 31, 2023
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accumulated depreciation and amortization on property, plant, and equipment	$ 13,000		$ 12,900
Antidilutive securities excluded from EPS calculations (in shares)	24	20
VillageMD Secured Loan | Line of Credit | Secured Debt
Accounts, Notes, Loans and Financing Receivable [Line Items]
Face amount				$ 2,250
VillageMD Secured Loan | Line of Credit | Revolving credit facilities
Accounts, Notes, Loans and Financing Receivable [Line Items]
Face amount				500
Pre-tax non-controlling interest benefit	$ 160
VillageMD Secured Loan | Line of Credit | Term Loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Face amount				$ 1,750
Related Party | Cencora
Accounts, Notes, Loans and Financing Receivable [Line Items]
Receivables	1,200		1,000
Trade Accounts Receivable
Accounts, Notes, Loans and Financing Receivable [Line Items]
Receivables	$ 5,000		$ 4,800