Accumulated other comprehensive income (loss) (Details) - USD ($) $ in Millions	3 Months Ended
	Nov. 30, 2021	Nov. 30, 2020
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	$ 23,822	$ 21,136
Total other comprehensive (loss) income	(196)	94
Ending balance	30,579	20,563
Pension/ post-retirement obligations
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(359)	(748)
Other comprehensive income (loss) before reclassification adjustments	(1)	17
Amounts reclassified from AOCI	(5)	(2)
Tax benefit (provision)	1	(4)
Total other comprehensive (loss) income	(5)	11
Ending balance	(364)	(736)
Unrealized gain (loss) on cash flow hedges
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(10)	(31)
Other comprehensive income (loss) before reclassification adjustments	1	4
Amounts reclassified from AOCI	1	1
Tax benefit (provision)	0	(1)
Total other comprehensive (loss) income	1	4
Ending balance	(9)	(27)
Net investment hedges
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(35)	(34)
Other comprehensive income (loss) before reclassification adjustments	53	(14)
Amounts reclassified from AOCI	0	0
Tax benefit (provision)	(9)	8
Total other comprehensive (loss) income	44	(7)
Ending balance	9	(41)
Unrealized gain (loss) on available for sale securities
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	96	0
Other comprehensive income (loss) before reclassification adjustments	450	0
Amounts reclassified from AOCI	(577)	0
Tax benefit (provision)	31	0
Total other comprehensive (loss) income	(96)	0
Ending balance	0	0
Share of OCI of equity method investments
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(29)	(10)
Other comprehensive income (loss) before reclassification adjustments	(60)	7
Amounts reclassified from AOCI	0	0
Tax benefit (provision)	14	(1)
Total other comprehensive (loss) income	(46)	5
Ending balance	(74)	(5)
Cumulative translation adjustments
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(1,772)	(2,948)
Other comprehensive income (loss) before reclassification adjustments	(88)	72
Amounts reclassified from AOCI	(4)	3
Tax benefit (provision)	0	0
Total other comprehensive (loss) income	(91)	75
Ending balance	(1,863)	(2,873)
Total
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(2,109)	(3,771)
Other comprehensive income (loss) before reclassification adjustments	356	85
Amounts reclassified from AOCI	(585)	2
Tax benefit (provision)	37	1
Total other comprehensive (loss) income	(193)	88
Ending balance	$ (2,301)	$ (3,682)