Supplemental information - Schedule of Redeemable Noncontrolling Interest (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Feb. 29, 2024	Feb. 28, 2023	Feb. 29, 2024	Feb. 28, 2023
Increase (Decrease) in Temporary Equity [Roll Forward]
Beginning balance	$ 169	$ 157	$ 167	$ 1,042
Net loss attributable to Redeemable non-controlling interests	2	(1)	2	(24)
Redemption price adjustments and other	2	3	0	454
Reclassifications from redeemable non-controlling interests	0	0	4	(1,314)
Ending balance	$ 172	$ 158	$ 172	$ 158

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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- Definition

The difference between the carrying amount of a financial instrument subject to a registration payment arrangement recorded as temporary equity prior to adoption of FSP EITF 00-19-2 and the carrying amount reclassified to permanent equity upon the adoption of FSP EITF 00-19-2. Recorded as a cumulative effect adjustment to the beginning balance of retained earnings. Does not apply to registration payment arrangements that are no longer outstanding upon adoption of FSP EITF 00-19-2.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 480
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 3A
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480244/480-10-S99-3A

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 815
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480237/815-40-50-3

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- Definition

Carrying amount, attributable to parent and noncontrolling interests, of an entity's issued and outstanding stock which is not included within permanent equity. Temporary equity is a security with redemption features that are outside the control of the issuer, is not classified as an asset or liability in conformity with GAAP, and is not mandatorily redeemable. Includes any type of security that is redeemable at a fixed or determinable price or on a fixed or determinable date or dates, is redeemable at the option of the holder, or has conditions for redemption which are not solely within the control of the issuer. Includes stock with a put option held by an ESOP and stock redeemable by a holder only in the event of a change in control of the issuer.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(g)(1)(ii))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480678/235-10-S99-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 323
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481687/323-10-50-3

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 28
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482907/825-10-50-28

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.27(b))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1

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- Definition

The portion of net income or loss attributable to temporary equity interest.

+ References

No definition available.

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- Definition

Amount of increase (decrease) in temporary equity from changes classified as other.

+ References

No definition available.

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