XML 32 R52.htm IDEA: XBRL DOCUMENT v2.4.0.6
Fair Value Measurement (Details) (USD $)
In Millions, unless otherwise specified
9 Months Ended
Dec. 31, 2011
Sep. 30, 2012
Senior Notes [Member]
Sep. 30, 2012
Debentures With Put Feature [Member]
Sep. 30, 2012
Recurring fair value measurements [Member]
Dec. 31, 2011
Recurring fair value measurements [Member]
Sep. 30, 2012
Recurring fair value measurements [Member]
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Dec. 31, 2011
Recurring fair value measurements [Member]
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Sep. 30, 2012
Recurring fair value measurements [Member]
Significant Other Observable Inputs (Level 2) [Member]
Dec. 31, 2011
Recurring fair value measurements [Member]
Significant Other Observable Inputs (Level 2) [Member]
Sep. 30, 2012
Recurring fair value measurements [Member]
Significant Unobservable Inputs (Level 3) [Member]
Dec. 31, 2011
Recurring fair value measurements [Member]
Significant Unobservable Inputs (Level 3) [Member]
Sep. 30, 2012
Nonrecurring fair value measurements [Member]
Dec. 31, 2011
Nonrecurring fair value measurements [Member]
Sep. 30, 2012
Nonrecurring fair value measurements [Member]
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Dec. 31, 2011
Nonrecurring fair value measurements [Member]
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Sep. 30, 2012
Nonrecurring fair value measurements [Member]
Significant Other Observable Inputs (Level 2) [Member]
Dec. 31, 2011
Nonrecurring fair value measurements [Member]
Significant Other Observable Inputs (Level 2) [Member]
Sep. 30, 2012
Nonrecurring fair value measurements [Member]
Significant Unobservable Inputs (Level 3) [Member]
Dec. 31, 2011
Nonrecurring fair value measurements [Member]
Significant Unobservable Inputs (Level 3) [Member]
Sep. 30, 2012
Financial Instruments not carried at fair value [Member]
Dec. 31, 2011
Financial Instruments not carried at fair value [Member]
Sep. 30, 2012
Financial Instruments not carried at fair value [Member]
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Dec. 31, 2011
Financial Instruments not carried at fair value [Member]
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Sep. 30, 2012
Financial Instruments not carried at fair value [Member]
Significant Other Observable Inputs (Level 2) [Member]
Dec. 31, 2011
Financial Instruments not carried at fair value [Member]
Significant Other Observable Inputs (Level 2) [Member]
Sep. 30, 2012
Financial Instruments not carried at fair value [Member]
Significant Unobservable Inputs (Level 3) [Member]
Dec. 31, 2011
Financial Instruments not carried at fair value [Member]
Significant Unobservable Inputs (Level 3) [Member]
Assets, fair value measurements [Abstract]                                                      
Marketable securities       $ 15.4 $ 10.4 $ 15.4 $ 10.4 $ 0 $ 0 $ 0 $ 0                                
Derivative instruments       18.0 9.3 0 0 18.0 9.3 0 0                                
Cash and cash equivalents                       929.6 1,160.7 929.6 1,160.7 0 0 0 0                
Total assets, fair value measurements       33.4 19.7 15.4 10.4 18.0 9.3 0 0                                
Total asset nonrecurring fair value measurements                       929.6 1,160.7 929.6 1,160.7 0 0 0 0                
Liabilities, fair value measurements [Abstract]                                                      
Derivative instruments       4.0 22.2 0 0 4.0 22.2 0 0                                
Total liability, fair value measurements       4.0 22.2 0 0 4.0 22.2 0 0                                
Total debt                                       3,764.7 4,359.2 0 0 3,764.7 4,359.2 0 0
Total financial instruments not carried at fair value                                       3,764.7 4,359.2 0 0 3,764.7 4,359.2 0 0
Benefit trust assets 169.5                                                    
Benefit trust liabilities $ 178.3                                                    
Debt instrument, maturity date range, start     Jan. 01, 2027                                                
Debt instrument, maturity date range, end   Dec. 31, 2025 Dec. 31, 2028