Fair value measurement - Narrative (Details)	12 Months Ended
	Dec. 31, 2025 USD ($) Investment	Dec. 31, 2024 USD ($)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity and debt investments, impairment loss	$ 12,300,000
Future funding commitments	100,000	$ 100,000
Unfunded commitments related funds	0
Level 2 | Fair Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of total long-term debt	$ 2,540,000,000	$ 2,980,000,000
Fair Value Measured at Net Asset Value Per Share | Defined Benefit Plan, Common Collective Trust | Retirement Plans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Number of investments held in collective trusts | Investment	4
Fair Value Measured at Net Asset Value Per Share | Common collective trust - fixed income | Retirement Plans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Number of investments held in collective trusts | Investment	3