Casualty, Environmental and Other Reserves (Details) (USD $)
In Millions, unless otherwise specified
Jun. 29, 2012
claims
Dec. 30, 2011
Jun. 01, 2010
May 31, 2010
All Contingencies Reserves [Line Items]        
Casualty, environmental and other reserves, current $ 171 $ 167    
Casualty, environmental and other reserves, noncurrent 327 352    
Casualty, environmental and other reserves, total 498 519    
Casualty
        
All Contingencies Reserves [Line Items]        
Casualty, environmental and other reserves, current 110 110    
Casualty, environmental and other reserves, noncurrent 242 262    
Casualty, environmental and other reserves, total 352 372    
Self-insured retention amount     50 25
Number of Claims Expected to Exceed Self Insured Retention Amount 0      
Personal Injury
        
All Contingencies Reserves [Line Items]        
Casualty, environmental and other reserves, current 93 93    
Casualty, environmental and other reserves, noncurrent 156 168    
Casualty, environmental and other reserves, total 249 261    
Occupational
        
All Contingencies Reserves [Line Items]        
Casualty, environmental and other reserves, current 6 6    
Casualty, environmental and other reserves, noncurrent 34 37    
Casualty, environmental and other reserves, total 40 43    
Asbestos
        
All Contingencies Reserves [Line Items]        
Casualty, environmental and other reserves, current 11 11    
Casualty, environmental and other reserves, noncurrent 52 57    
Casualty, environmental and other reserves, total 63 68    
Environmental
        
All Contingencies Reserves [Line Items]        
Casualty, environmental and other reserves, current 39 31    
Casualty, environmental and other reserves, noncurrent 42 52    
Casualty, environmental and other reserves, total 81 83    
Environmental impaired sites 263      
Other
        
All Contingencies Reserves [Line Items]        
Casualty, environmental and other reserves, current 22 [1] 26 [1]    
Casualty, environmental and other reserves, noncurrent 43 [1] 38 [1]    
Casualty, environmental and other reserves, total $ 65 [1] $ 64 [1]    
[1] Separation liabilities and freight rate dispute reserves have been reclassified to other current and long-term liabilities.