v2.4.0.6
Consolidated Balance Sheet (Parenthetical) (USD $)
Dec. 31, 2011
Dec. 31, 2010
Consolidated Balance Sheet [Abstract]    
Common stock, without par value      
Common stock, shares authorized 9,000,000,000 9,000,000,000
Common stock, shares issued 8,019,000,000 8,019,000,000
Common stock held in treasury, shares 3,285,000,000 3,040,000,000