v2.4.0.8
Basis of presentation and summary of significant accounting policies (Details 2) (USD $)
3 Months Ended 6 Months Ended
Jun. 30, 2013
Jun. 30, 2012
Jun. 30, 2013
Jun. 30, 2012
Changes in accumulated other comprehensive loss by component        
Balance at beginning of period     $ 9,400,000  
Other comprehensive loss:        
Foreign currency translation adjustments (18,000,000) (13,900,000) (30,100,000) 3,300,000
Net change from periodic revaluations 100,000 200,000 400,000 500,000
Tax benefit 600,000 (5,300,000) (1,900,000) (22,200,000)
Total Other comprehensive income (loss) (17,300,000) (14,200,000) (29,100,000) 3,300,000
Balance at end of period (19,500,000)   (19,500,000)  
Foreign currency translation
       
Changes in accumulated other comprehensive loss by component        
Balance at beginning of period 600,000 13,800,000 12,700,000 (3,400,000)
Other comprehensive loss:        
Foreign currency translation adjustments (18,000,000) (13,900,000) 30,100,000 3,300,000
Balance at end of period (17,400,000) (100,000) (17,400,000) (100,000)
Cash flow hedges
       
Changes in accumulated other comprehensive loss by component        
Balance at beginning of period (1,100,000) (1,100,000) (1,400,000) (1,400,000)
Other comprehensive loss:        
Net change from periodic revaluations 1,000,000 (800,000) 1,000,000 (800,000)
Tax (expense) benefit (400,000) 300,000 (400,000) 300,000
Total Other comprehensive income (loss) before reclassifications, net of tax 600,000 (500,000) 600,000 (500,000)
Tax benefit 200,000 100,000 200,000 300,000
Total amount reclassified from Accumulated other comprehensive loss, net of tax 100,000 200,000 400,000 500,000
Total Other comprehensive income (loss) 700,000 (300,000) 100,000  
Balance at end of period (400,000) (1,400,000) (400,000) (1,400,000)
Cash flow hedges | Amount reclassified from accumulated other comprehensive income
       
Other comprehensive loss:        
Net amount reclassified to earnings: 300,000 300,000 600,000 800,000
Cash flow hedges | Amount reclassified from accumulated other comprehensive income | Interest rate swaps
       
Other comprehensive loss:        
Net amount reclassified to earnings: 400,000 300,000 800,000 800,000
Cash flow hedges | Amount reclassified from accumulated other comprehensive income | Fuel commodity swaps
       
Other comprehensive loss:        
Net amount reclassified to earnings: $ (100,000)   $ (200,000)