Stockholders' equity - Components of Accumulated Other Comprehensive Income (Details) $ in Millions	3 Months Ended
	Mar. 31, 2024 USD ($)
Increase (Decrease) in AOCI [Roll Forward]
Beginning balance	$ 6,232
Ending balance	5,022
Foreign currency translation
Increase (Decrease) in AOCI [Roll Forward]
Beginning balance	(298)
Foreign currency translation adjustments	(24)
Unrealized gains	0
Reclassification adjustments to income	0
Other	0
Income taxes	0
Ending balance	(322)
Cash flow hedges
Increase (Decrease) in AOCI [Roll Forward]
Beginning balance	(22)
Foreign currency translation adjustments	0
Unrealized gains	178
Reclassification adjustments to income	(20)
Other	0
Income taxes	(32)
Ending balance	104
Other
Increase (Decrease) in AOCI [Roll Forward]
Beginning balance	31
Foreign currency translation adjustments	0
Unrealized gains	0
Reclassification adjustments to income	0
Other	(3)
Income taxes	0
Ending balance	28
AOCI
Increase (Decrease) in AOCI [Roll Forward]
Beginning balance	(289)
Foreign currency translation adjustments	(24)
Unrealized gains	178
Reclassification adjustments to income	(20)
Other	(3)
Income taxes	(32)
Ending balance	$ (190)