v2.4.0.6
Postretirement Benefit Plans (Details Textual) (USD $)
In Millions, unless otherwise specified
3 Months Ended
Mar. 31, 2013
Mar. 31, 2012
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block    
Net Periodic Benefit Cost $ 1  
Postretirement Benefit Plans (Textual) [Abstract]    
Employer Contribution to definer benefit Plan 11 9
Minimum
   
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block    
Additional contributions 27  
Maximum
   
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block    
Additional contributions $ 37