Subsequent events (Details) - Subsequent event - Senior notes $ in Billions	Oct. 31, 2025 USD ($)
4.400% Guaranteed Notes due 2031
Subsequent Event [Line Items]
Debt Instrument, Face Amount	$ 1.0
Debt instrument, stated percentage	4.40%
5.000% Guaranteed Notes due 2036
Subsequent Event [Line Items]
Debt Instrument, Face Amount	$ 1.0
Debt instrument, stated percentage	5.00%
5.600% Guaranteed Notes due 2056
Subsequent Event [Line Items]
Debt Instrument, Face Amount	$ 0.5
Debt instrument, stated percentage	5.60%