XML 32 R40.htm IDEA: XBRL DOCUMENT v2.4.0.8
Incentive Award Plan and Employee Stock Purchase Plan (Compensation Expense) (Details) (USD $)
In Millions, unless otherwise specified
3 Months Ended 6 Months Ended
Jun. 30, 2013
Jun. 30, 2012
Jun. 30, 2013
Jun. 30, 2012
Employee Service Share-based Compensation, Allocation of Recognized Period Costs        
Allocated Share-based Compensation Expense $ 3.5 $ 2.3 $ 6.0 $ 3.5