v3.3.1.900
Changes in accumulated other comprehensive loss by component (Details) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Changes in accumulated other comprehensive loss by component      
Balance at beginning of period $ (68.3)   $ (1.8)
Other comprehensive income (loss):      
Foreign currency translation adjustments (72.8) $ (44.1) (34.8)
Tax expense (30.4) (31.4) (32.8)
Total Other comprehensive income (loss) (71.0) (45.9) (31.8)
Balance at end of period (139.3) (68.3)  
Accumulated other comprehensive loss, tax impacts related to rate changes 0.0 0.0 0.0
Foreign currency translation      
Changes in accumulated other comprehensive loss by component      
Balance at beginning of period (66.3) (22.2) 12.6
Other comprehensive income (loss):      
Foreign currency translation adjustments (72.8) (44.1) (34.8)
Balance at end of period (139.1) (66.3) (22.2)
Cash flow hedges      
Changes in accumulated other comprehensive loss by component      
Balance at beginning of period 0.1 0.2 (1.4)
Other comprehensive income (loss):      
Tax (expense) benefit 0.4 0.7 (0.5)
Total Other comprehensive income (loss) before reclassifications, net of tax (0.6) (1.0) 0.7
Net change from periodic revaluations (1.0) (1.7) 1.2
Total Other comprehensive income (loss) 0.1 (0.1) 1.6
Balance at end of period 0.2 0.1 0.2
Cash flow hedges | Amount reclassified from accumulated other comprehensive income      
Other comprehensive income (loss):      
Total amount reclassified from Accumulated other comprehensive loss, net of tax 0.7 0.9 0.9
Net amount reclassified to earnings (loss): 1.3 1.5 1.5
Tax expense (0.6) (0.6) (0.6)
Cash flow hedges | Amount reclassified from accumulated other comprehensive income | Interest rate swaps | Interest expense, net      
Other comprehensive income (loss):      
Net amount reclassified to earnings (loss): 1.3 1.5 1.7
Cash flow hedges | Amount reclassified from accumulated other comprehensive income | Fuel commodity swaps      
Other comprehensive income (loss):      
Net amount reclassified to earnings (loss):     (0.2)
Pension      
Changes in accumulated other comprehensive loss by component      
Balance at beginning of period (2.1) (0.4)  
Other comprehensive income (loss):      
Unrecognized net actuarial gain (loss) 2.2 (2.3) 2.4
Tax (expense) benefit (0.6) 0.6 (0.7)
Total Other comprehensive income (loss) before reclassifications, net of tax 1.6 (1.7) 1.7
Total Other comprehensive income (loss) 1.7 (1.7) 1.4
Balance at end of period (0.4) $ (2.1) (0.4)
Pension | Amount reclassified from accumulated other comprehensive income      
Other comprehensive income (loss):      
Tax (expense) benefit     0.1
Amortization of net actuarial gain 0.1   (0.4)
Total amount reclassified from Accumulated other comprehensive loss, net of tax $ 0.1   $ (0.3)