Stockholders' equity - Schedule of Components of AOCI (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	$ 5,877	$ 6,232	$ 3,661
Foreign currency translation adjustments	172	(76)	50
Unrealized gains	(250)	506	28
Reclassification adjustments into earnings	(231)	(117)	(222)
Other	13	(10)	42
Income taxes	104	(80)	44
Ending balance	8,658	5,877	6,232
Foreign currency translation adjustments
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	(374)	(298)	(348)
Foreign currency translation adjustments	172	(76)	50
Unrealized gains	0	0	0
Reclassification adjustments into earnings	0	0	0
Other	0	0	0
Income taxes	0	0	0
Ending balance	(202)	(374)	(298)
Cash flow hedges
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	287	(22)	128
Foreign currency translation adjustments	0	0	0
Unrealized gains	(250)	506	28
Reclassification adjustments into earnings	(231)	(117)	(222)
Other	0	0	0
Income taxes	104	(80)	44
Ending balance	(90)	287	(22)
Other
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	21	31	(11)
Foreign currency translation adjustments	0	0	0
Unrealized gains	0	0	0
Reclassification adjustments into earnings	0	0	0
Other	13	(10)	42
Income taxes	0	0	0
Ending balance	34	21	31
AOCI
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	(66)	(289)	(231)
Ending balance	$ (258)	$ (66)	$ (289)

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