Earnings per share - Computation for Basic and Diluted Earnings per Share (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Income (Numerator):
Net (loss) income for basic and diluted (loss) earnings per share	$ (113)	$ 2,841
Shares (Denominator):
Weighted-average shares for basic (loss) earnings per share (in shares)	536	534
Effect of dilutive securities (in shares)	0	4
Weighted-average shares for diluted (loss) earnings per share (in shares)	536	538
Basic (loss) earnings per share (in usd per share)	$ (0.21)	$ 5.32
Diluted (loss) earnings per share (in usd per share)	$ (0.21)	$ 5.28