v2.4.0.6
Income Taxes (Summary Of The Tax Years By Jurisdiction That Remain Subject To Examination By Taxing Authorities) (Details)
12 Months Ended
Dec. 31, 2011
U. S. Federal [Member]
 
Open Tax Years by Major Tax Jurisdiction 2008-2011
Various U.S. States [Member]
 
Open Tax Years by Major Tax Jurisdiction 2007-2011
Canada Federal [Member]
 
Open Tax Years by Major Tax Jurisdiction 2003-2011
Various Canadian Provinces [Member]
 
Open Tax Years by Major Tax Jurisdiction 2003-2011