Accumulated other comprehensive loss (Details) - USD ($) $ in Millions	3 Months Ended
	Nov. 30, 2024	Nov. 30, 2023
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	$ 12,005	$ 28,322
Total other comprehensive loss	(80)	(5)
Ending balance	11,165	27,588
Pension/ post-retirement obligations
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	(706)	(698)
Other comprehensive income (loss) before reclassification adjustments	0	77
Amounts reclassified from AOCI	5	(2)
Tax provision	(1)	(19)
Total other comprehensive loss	4	56
Ending balance	(702)	(642)
Unrealized gain (loss) on cash flow hedges and other
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	(1)	(6)
Other comprehensive income (loss) before reclassification adjustments	1	1
Amounts reclassified from AOCI	0	4
Tax provision	0	0
Total other comprehensive loss	0	5
Ending balance	0	(1)
Net investment hedges gain
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	15	83
Other comprehensive income (loss) before reclassification adjustments	92	8
Amounts reclassified from AOCI	0	(4)
Tax provision	0	(1)
Total other comprehensive loss	92	3
Ending balance	107	86
Share of OCI of equity method investments
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	(88)	(132)
Other comprehensive income (loss) before reclassification adjustments	30	(28)
Amounts reclassified from AOCI	0	8
Tax provision	0	5
Total other comprehensive loss	30	(15)
Ending balance	(58)	(147)
Cumulative translation adjustments
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	(2,118)	(2,240)
Other comprehensive income (loss) before reclassification adjustments	(200)	(49)
Amounts reclassified from AOCI	0	(2)
Tax provision	0	0
Total other comprehensive loss	(200)	(51)
Ending balance	(2,318)	(2,291)
Total
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	(2,897)	(2,993)
Other comprehensive income (loss) before reclassification adjustments	(77)	9
Amounts reclassified from AOCI	5	3
Tax provision	(1)	(14)
Total other comprehensive loss	(74)	(2)
Ending balance	$ (2,971)	$ (2,995)