Income taxes - Provision for Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Income Tax Disclosure [Abstract]
Taxes calculated using the estimated annual effective tax rate	$ 227	$ 229	$ 573	$ 794
Discrete tax items	(35)	(16)	(73)	(63)
Provision for income taxes	$ 192	$ 213	$ 500	$ 731
Effective tax rate	12.00%	11.00%	12.00%	12.00%