Income taxes (Details) $ in Millions	Sep. 30, 2024 USD ($)
Income Tax Disclosure [Abstract]
Unrecognized tax benefits	$ 99
Unrecognized tax benefits that would impact effective tax rate if recognized	99
Accrued interest related to the gross unrecognized tax benefits excluded from the unrecognized tax benefits	26
Accrued penalties related to the gross unrecognized tax benefits excluded from the unrecognized tax benefits	2
Decrease in unrecognized tax benefits that is reasonably possible (up to)	$ 40

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

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Amount of unrecognized tax benefits.

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Amount of statutory penalties accrued for a tax position claimed or expected to be claimed by the entity, in its tax return.

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Amount of interest expense accrued for an underpayment of income taxes.

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The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

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