v3.26.1
Fair value of financial instruments - Net Investment Hedges (Details) - USD ($)
$ in Millions
3 Months Ended 6 Months Ended
Jun. 30, 2026
Jun. 30, 2025
Jun. 30, 2026
Jun. 30, 2025
Dec. 31, 2025
Derivative [Line Items]          
Interest expense $ (62.9) $ (60.9) $ (126.4) $ (118.4)  
Level 2 | Designated as Hedging Instrument          
Derivative [Line Items]          
Fair value of contract, liability position (54.8)   (54.8)   $ (61.3)
$400 million cross currency swap 2022 | Level 2 | Designated as Hedging Instrument          
Derivative [Line Items]          
Interest expense (1.3) $ (1.2) (2.8) $ (2.4)  
$215 million cross currency swap II | Designated as Hedging Instrument          
Derivative [Line Items]          
Notional value of derivative instrument 215.0   215.0    
Other foreign exchange forward swaps | Designated as Hedging Instrument          
Derivative [Line Items]          
Notional value of derivative instrument 145.0   $ 145.0    
Weighted average maturity     1 year    
$215 million cross currency swap III | Designated as Hedging Instrument          
Derivative [Line Items]          
Notional value of derivative instrument 215.0   $ 215.0    
Weighted average maturity     9 months 18 days    
$185 million cross currency swap | Designated as Hedging Instrument          
Derivative [Line Items]          
Notional value of derivative instrument 185.0   $ 185.0    
Weighted average maturity     4 years 3 months 18 days    
Location, Statement of Financial Position, Balance [Axis]: us-gaap:AccruedLiabilitiesCurrent | $400 million cross currency swap 2022 | Level 2 | Designated as Hedging Instrument          
Derivative [Line Items]          
Fair value of contract, liability position (29.2)   $ (29.2)   (34.2)
Location, Statement of Financial Position, Balance [Axis]: us-gaap:AccruedLiabilitiesCurrent | Other foreign exchange forward swaps | Level 2 | Designated as Hedging Instrument          
Derivative [Line Items]          
Fair value of contract, liability position 0.0   0.0   (0.7)
Location, Statement of Financial Position, Balance [Axis]: us-gaap:OtherAssetsNoncurrent | Other foreign exchange forward swaps | Level 2 | Designated as Hedging Instrument          
Derivative [Line Items]          
Fair value of contract, asset position 0.3   0.3   0.2
Location, Statement of Financial Position, Balance [Axis]: us-gaap:OtherLiabilitiesNoncurrent | $400 million cross currency swap 2022 | Level 2 | Designated as Hedging Instrument          
Derivative [Line Items]          
Fair value of contract, liability position (25.8)   (25.8)   (28.3)
Location, Statement of Financial Position, Balance [Axis]: us-gaap:OtherLiabilitiesNoncurrent | Other foreign exchange forward swaps | Level 2 | Designated as Hedging Instrument          
Derivative [Line Items]          
Fair value of contract, liability position (3.9)   (3.9)   (1.1)
Location, Statement of Financial Position, Balance [Axis]: us-gaap:PrepaidExpenseCurrent | $400 million cross currency swap 2022 | Level 2 | Designated as Hedging Instrument          
Derivative [Line Items]          
Fair value of contract, asset position 2.1   2.1   2.1
Location, Statement of Financial Position, Balance [Axis]: us-gaap:PrepaidExpenseCurrent | $215 million cross currency swap II | Level 2 | Designated as Hedging Instrument          
Derivative [Line Items]          
Fair value of contract, asset position 0.0   0.0   0.2
Location, Statement of Financial Position, Balance [Axis]: us-gaap:PrepaidExpenseCurrent | Other foreign exchange forward swaps | Level 2 | Designated as Hedging Instrument          
Derivative [Line Items]          
Fair value of contract, asset position $ 1.7   $ 1.7   $ 0.5