Stockholders' equity - Schedule of Components of AOCI (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2026	Jun. 30, 2026
Increase (Decrease) in AOCI [Roll Forward]
Beginning balance	$ 9,190	$ 8,658
Ending balance	11,688	11,688
Foreign currency translation adjustments
Increase (Decrease) in AOCI [Roll Forward]
Beginning balance	(207)	(202)
Foreign currency translation adjustments	(22)	(27)
Unrealized gains	0	0
Reclassification adjustments into earnings	0	0
Other	0	0
Income taxes	0	0
Ending balance	(229)	(229)
Cash flow hedges
Increase (Decrease) in AOCI [Roll Forward]
Beginning balance	(13)	(90)
Foreign currency translation adjustments	0	0
Unrealized gains	113	98
Reclassification adjustments into earnings	4	117
Other	0	0
Income taxes	(23)	(44)
Ending balance	81	81
Other
Increase (Decrease) in AOCI [Roll Forward]
Beginning balance	30	34
Foreign currency translation adjustments	0	0
Unrealized gains	0	0
Reclassification adjustments into earnings	0	0
Other	(1)	(5)
Income taxes	0	0
Ending balance	29	29
AOCI
Increase (Decrease) in AOCI [Roll Forward]
Beginning balance	(190)	(258)
Foreign currency translation adjustments	(22)	(27)
Unrealized gains	113	98
Reclassification adjustments into earnings	4	117
Other	(1)	(5)
Income taxes	(23)	(44)
Ending balance	$ (119)	$ (119)

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Amount of tax expense (benefit) allocated to other comprehensive income (loss) attributable to parent entity.

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