Accumulated other comprehensive loss - Reclassification out of accumulated other comprehensive income (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other nonoperating income, net	$ 4	$ 20
Income tax benefit	(55)	(58)
Total	176	94
Reclassifications from Accumulated other comprehensive loss to income
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Total	(4)	(9)
Reclassifications from Accumulated other comprehensive loss to income | Cash flow hedges
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Cost of product revenues	(2)	(2)
Total	(2)	(2)
Reclassifications from Accumulated other comprehensive loss to income | Pension and other postretirement plans
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other nonoperating income, net	(2)	(8)
Income tax benefit	0	1
Total	$ (2)	$ (7)