Stockholders' equity - Narrative (Details) - USD ($) $ / shares in Units, $ in Billions	1 Months Ended			3 Months Ended
	Jun. 30, 2024	Mar. 31, 2024	Dec. 31, 2023	Mar. 31, 2024	Mar. 31, 2023
Class of Stock [Line Items]
Amount available for stock repurchases under a board approved stock repurchase plan		$ 7.0		$ 7.0
Dividends declared per share (in usd per share)		$ 2.25	$ 2.25	$ 2.25	$ 2.13
Dividends paid per share (in usd per share)		$ 2.25
Forecast
Class of Stock [Line Items]
Dividends paid per share (in usd per share)	$ 2.25