v2.4.0.6
Net Periodic Benefit Cost for Company Sponsored Pension and Postretirement Benefit Plans (Detail) (USD $)
In Millions, unless otherwise specified
 12 Months Ended
Dec. 31, 2011
Dec. 31, 2010
Dec. 31, 2009
U.S. Pension Benefits
      
Net Periodic Cost:      
Service cost $ 870 $ 723 $ 689
Interest cost 1,309 1,199 1,130
Expected return on assets (1,835) (1,381) (1,151)
Amortization of:      
Transition obligation     4
Prior service cost 171 172 178
Actuarial (gain) loss 736 70  
Other     3
Net periodic benefit cost 1,251 783 853
U.S. Postretirement Medical Benefits
      
Net Periodic Cost:      
Service cost 89 86 85
Interest cost 207 214 211
Expected return on assets (16) (22) (27)
Amortization of:      
Prior service cost 7 4 6
Net periodic benefit cost 287 282 275
International Pension Benefits
      
Net Periodic Cost:      
Service cost 34 24 17
Interest cost 39 34 28
Expected return on assets (43) (36) (26)
Amortization of:      
Prior service cost 1 1 1
Actuarial (gain) loss 91 42 16
Other   6 1
Net periodic benefit cost $ 122 $ 71 $ 37