Income taxes - Provision for Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Income Tax Disclosure [Abstract]
Taxes calculated using the estimated annual effective tax rate	$ 176	$ 276
Discrete tax items	12	(38)
Provision for income taxes	$ 188	$ 238
Effective tax rate	14.50%	12.20%