Accumulated other comprehensive income (loss) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	May 31, 2023	May 31, 2022	May 31, 2023	May 31, 2022
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	$ 29,439	$ 30,867	$ 29,366	$ 23,822
Net change in other comprehensive (loss) income	121	(416)	274	(637)
Ending balance	29,359	30,382	29,359	30,382
Pension/ post retirement obligations
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(167)	(372)	(157)	(359)
Other comprehensive (loss) income before reclassification adjustments	0	0	0	0
Amounts reclassified from AOCI	(7)	(5)	(20)	(16)
Other				(6)
Tax benefit (provision)	2	1	5	5
Net change in other comprehensive (loss) income	(5)	(4)	(15)	(17)
Ending balance	(171)	(376)	(171)	(376)
Unrealized loss on cash flow hedges
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(5)	(9)	(3)	(10)
Other comprehensive (loss) income before reclassification adjustments	(2)	4	(5)	5
Amounts reclassified from AOCI	1	1	2	2
Other				0
Tax benefit (provision)	0	(1)	0	(1)
Net change in other comprehensive (loss) income	(1)	4	(3)	6
Ending balance	(6)	(5)	(6)	(5)
Net investment hedges
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	140	(11)	213	(35)
Other comprehensive (loss) income before reclassification adjustments	(42)	176	(138)	207
Amounts reclassified from AOCI	0	0	0	0
Other				0
Tax benefit (provision)	10	(40)	33	(48)
Net change in other comprehensive (loss) income	(31)	135	(104)	159
Ending balance	108	124	108	124
Unrealized gain (loss) on available for sale securities
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance			1	96
Other comprehensive (loss) income before reclassification adjustments			(1)	450
Amounts reclassified from AOCI			0	(577)
Other				0
Tax benefit (provision)			0	31
Net change in other comprehensive (loss) income			(1)	(96)
Ending balance	0	0	0	0
Share of OCI of equity method investments
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(162)	(154)	(254)	(29)
Other comprehensive (loss) income before reclassification adjustments	16	(48)	(8)	(213)
Amounts reclassified from AOCI	(1)	25	149	25
Other				0
Tax benefit (provision)	(4)	6	(37)	46
Net change in other comprehensive (loss) income	12	(17)	104	(143)
Ending balance	(150)	(171)	(150)	(171)
Cumulative translation adjustments
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(2,461)	(1,782)	(2,605)	(1,772)
Other comprehensive (loss) income before reclassification adjustments	143	(515)	301	(525)
Amounts reclassified from AOCI	(2)	0	(16)	0
Other				0
Tax benefit (provision)	0	0	0	0
Net change in other comprehensive (loss) income	141	(515)	285	(525)
Ending balance	(2,320)	(2,297)	(2,320)	(2,297)
Total
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(2,654)	(2,328)	(2,805)	(2,109)
Other comprehensive (loss) income before reclassification adjustments	115	(383)	149	(77)
Amounts reclassified from AOCI	(9)	20	115	(566)
Other				(6)
Tax benefit (provision)	9	(34)	2	32
Net change in other comprehensive (loss) income	115	(397)	266	(616)
Ending balance	$ (2,539)	$ (2,724)	$ (2,539)	$ (2,724)