Income taxes (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Statement [line items]
Income before taxes	$ 8,371	$ 26,137	$ 9,878
Switzerland
Statement [line items]
Income before taxes	5,986	22,028	9,786
Foreign
Statement [line items]
Income before taxes	$ 2,385	$ 4,109	$ 92

The profit (loss) before tax expense or income. [Refer: Profit (loss)]

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