Income taxes (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
May 31, 2021	May 31, 2020	May 31, 2021	May 31, 2020
Income Tax Examination [Line Items]
Effective tax rate	32.80%	2.30%	7.40%	230.00%
Equity earnings			$ (577)	$ 297
Income taxes paid			305	$ 604
Amount of potential decrease in unrecognized tax benefits during next twelve months	$ 110		$ 110
Option Care Health
Income Tax Examination [Line Items]
Equity earnings	$ 576

Amount of decrease reasonably possible in the next twelve months for the unrecognized tax benefit.

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Amount of income (loss) for proportionate share of equity method investee's income (loss).

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The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income, net of any cash received during the current period as refunds for the overpayment of taxes.

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