XML 131 R58.htm IDEA: XBRL DOCUMENT v2.4.0.8
Investments in Marketable Securities - Summary of cost, gross unrealized gains, gross unrealized losses and fair value (Details) (Equity securities [Member], USD $)
In Millions, unless otherwise specified
 12 Months Ended
Dec. 31, 2013
Dec. 31, 2012
Equity securities [Member]
    
Available-for-Sale    
Cost $ 103.2 $ 103.2
Unrealized Gains 33.3 15.3
Unrealized Losses (1.1) (3.2)
Fair Value 135.4 115.3
Trading    
Cost 17.9 10.3
Unrealized Gains 4.6 6.5
Unrealized Losses 0 (3.2)
Fair Value $ 22.5 $ 13.6