v2.4.0.8
Fair value of financial instruments (Details) (USD $)
In Millions, unless otherwise specified
3 Months Ended 6 Months Ended 6 Months Ended 12 Months Ended
Jun. 30, 2013
Jun. 30, 2012
Jun. 30, 2013
Jun. 30, 2012
Dec. 31, 2012
Jun. 30, 2013
Credit valuation adjustments
Dec. 31, 2012
Credit valuation adjustments
Dec. 31, 2012
Credit valuation adjustments
Foreign currency forward contracts
Jun. 30, 2013
Recurring
Level 1
Dec. 31, 2012
Recurring
Level 1
Jun. 30, 2013
Recurring
Level 2
Dec. 31, 2012
Recurring
Level 2
Jun. 30, 2013
Recurring
Total
Dec. 31, 2012
Recurring
Total
Assets:                            
Cash and cash equivalents                 $ 195.6 $ 60.2     $ 195.6 $ 60.2
Restricted cash 40.1   40.1   28.6       40.1 28.6     40.1 28.6
Derivative instruments asset                     9.0 20.6 9.0 20.6
Total                 235.7 88.8 9.0 20.6 244.7 109.4
Liabilities:                            
Derivative instruments liability                     114.2 151.1 114.2 151.1
Total                     114.2 151.1 114.2 151.1
Net increase in fair value           12.0 18.4              
Pre-tax increase in other comprehensive income           0.6 1.0              
Increase in change in fair value of derivatives           11.4 13.8              
Foreign exchange loss (gain) $ (14.5) $ (4.2) $ (22.0) $ (3.2)       $ 3.6