v3.19.3.a.u2
Changes in accumulated other comprehensive income by component (Details) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
AOCI Attributable to Parent, Net of Tax      
Beginning Balance $ (6.9)    
Amount reclassified      
Ending Balance (45.0) $ (6.9)  
Foreign currency translation      
AOCI Attributable to Parent, Net of Tax      
Beginning Balance (146.4) (134.3) $ (148.3)
Other comprehensive income (loss):      
Foreign currency translation adjustments 5.8 (12.1) 14.0
Amount reclassified      
Ending Balance (140.6) (146.4) (134.3)
Accumulated other comprehensive loss, tax impacts related to rate changes 0.0 0.0 0.0
Pension      
AOCI Attributable to Parent, Net of Tax      
Beginning Balance (1.4) (1.6) (0.9)
Other comprehensive income (loss):      
Settlement 0.3    
Curtailment gain     (1.6)
Tax expense (0.1)   0.4
Total Other comprehensive income (loss) before reclassifications, net of tax 0.2   (1.2)
Amount reclassified      
Total other comprehensive (loss) income (0.3) 0.2 (0.7)
Ending Balance (1.7) (1.4) (1.6)
Cash flow hedges      
AOCI Attributable to Parent, Net of Tax      
Beginning Balance 1.6 1.1 0.7
Other comprehensive income (loss):      
Net change from periodic revaluations (0.5) 0.5 (0.2)
Tax expense 0.2 (0.1) 0.1
Total Other comprehensive income (loss) before reclassifications, net of tax (0.3) 0.4 (0.1)
Amount reclassified      
Total other comprehensive (loss) income   0.5 0.4
Ending Balance 1.6 1.6 1.1
Amount reclassified from accumulated other comprehensive income | Foreign currency translation      
Amount reclassified      
Amounts reclassified to earnings, foreign currency 0.0 0.0 0.0
Amount reclassified from accumulated other comprehensive income | Pension      
Amount reclassified      
Total amount reclassified from accumulated other comprehensive (loss) income, net of tax (0.5) 0.2 0.5
Amount reclassified from accumulated other comprehensive income | Cash flow hedges      
Amount reclassified      
Tax benefit (expense) (0.1) (0.1) (0.4)
Total amount reclassified from accumulated other comprehensive (loss) income, net of tax (0.3) (0.1) (0.5)
Amount reclassified from accumulated other comprehensive income | Cash flow hedges | Interest rate swaps      
Amount reclassified      
Interest rate swaps $ 0.4 $ 0.2 $ 0.9