Accumulated other comprehensive loss (Details) - USD ($) $ in Millions	12 Months Ended
	Aug. 31, 2024	Aug. 31, 2023	Aug. 31, 2022
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	$ 28,322	$ 29,366	$ 23,822
Total other comprehensive income (loss)	100	(176)	(728)
Ending balance	12,005	28,322	29,366
Accumulated other comprehensive loss
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	(2,993)	(2,805)	(2,109)
Other comprehensive income (loss) before reclassification adjustments	68	(500)	(97)
Amounts reclassified from AOCI	51	121	(565)
Other			(6)
Tax (provision) benefit	(23)	190	(27)
Total other comprehensive income (loss)	96	(189)	(696)
Ending balance	(2,897)	(2,993)	(2,805)
Pension/post-retirement obligations
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	(698)	(157)	(359)
Other comprehensive income (loss) before reclassification adjustments	14	(705)	278
Amounts reclassified from AOCI	(14)	(26)	(22)
Other			(6)
Tax (provision) benefit	(8)	190	(48)
Total other comprehensive income (loss)	(8)	(541)	203
Ending balance	(706)	(698)	(157)
Unrealized gain (loss) on cash flow hedges
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	(5)	(3)	(10)
Other comprehensive income (loss) before reclassification adjustments	0	(7)	6
Amounts reclassified from AOCI	8	4	3
Other			0
Tax (provision) benefit	(3)	0	(2)
Total other comprehensive income (loss)	5	(2)	7
Ending balance	(1)	(5)	(3)
Net investment hedges (loss) gain
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	83	213	(35)
Other comprehensive income (loss) before reclassification adjustments	(65)	(172)	327
Amounts reclassified from AOCI	(4)	0	0
Other			0
Tax (provision) benefit	1	42	(79)
Total other comprehensive income (loss)	(68)	(130)	248
Ending balance	15	83	213
Unrealized gain (loss) on available for sale debt securities
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	0	1	96
Other comprehensive income (loss) before reclassification adjustments	0	(2)	451
Amounts reclassified from AOCI	0	0	(577)
Other			0
Tax (provision) benefit	1	1	32
Total other comprehensive income (loss)	1	(2)	(95)
Ending balance	0	0	1
Share of OCI of equity method investments
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	(132)	(254)	(29)
Other comprehensive income (loss) before reclassification adjustments	(6)	6	(326)
Amounts reclassified from AOCI	63	158	31
Other			0
Tax (provision) benefit	(13)	(42)	70
Total other comprehensive income (loss)	45	122	(226)
Ending balance	(88)	(132)	(254)
Cumulative translation adjustments
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	(2,240)	(2,605)	(1,772)
Other comprehensive income (loss) before reclassification adjustments	124	379	(833)
Amounts reclassified from AOCI	(2)	(14)	0
Other			0
Tax (provision) benefit	0	0	0
Total other comprehensive income (loss)	122	364	(833)
Ending balance	$ (2,118)	$ (2,240)	$ (2,605)