v2.4.0.6
Debt (Details 2)
12 Months Ended
Dec. 31, 2011
USD ($)
Dec. 31, 2010
USD ($)
Dec. 31, 2009
USD ($)
Dec. 31, 2011
EUR (€)
Credit facilities        
Weighted average daily interest rate 2.70% 2.47% 1.62%  
Weighted average daily borrowings $ 870,900,000 $ 501,100,000 $ 1,641,900,000  
Maximum borrowings outstanding at any month-end 2,368,100,000 1,010,200,000 3,285,300,000  
Aggregate borrowing capacity 2,184,600,000 1,601,500,000 2,164,800,000 487,500,000
Borrowings outstanding 934,900,000 520,100,000 736,600,000  
Outstanding letters of credit 85,000,000 88,200,000 114,900,000  
Aggregate remaining capacity available $ 1,164,700,000 $ 993,200,000 $ 1,080,400,000