Property, plant and equipment - Useful lives of property, plant and equipment (Detail)	12 Months Ended
	Dec. 31, 2025
Buildings \| Bottom of range
Property, plant and equipment [Line Items]
Useful life measured as period of time, property, plant and equipment	5 years
Buildings \| Top of range
Property, plant and equipment [Line Items]
Useful life measured as period of time, property, plant and equipment	50 years
Machinery and installations \| Bottom of range
Property, plant and equipment [Line Items]
Useful life measured as period of time, property, plant and equipment	3 years
Machinery and installations \| Top of range
Property, plant and equipment [Line Items]
Useful life measured as period of time, property, plant and equipment	20 years
Other equipment \| Bottom of range
Property, plant and equipment [Line Items]
Useful life measured as period of time, property, plant and equipment	1 year
Other equipment \| Top of range
Property, plant and equipment [Line Items]
Useful life measured as period of time, property, plant and equipment	10 years