v2.3.0.11
Retirement Plans (Details) (USD $)
In Millions
3 Months Ended 6 Months Ended
Jun. 30, 2011
Jun. 30, 2010
Jun. 30, 2011
Jun. 30, 2010
Pension [Member]
       
Net Periodic Cost/(Benefit) [Abstract]        
Service cost $ 11 $ 11 $ 22 $ 22
Interest cost 36 35 72 70
Expected return on plan assets (45) (44) (90) (89)
Amortization of prior service cost/(credit) 0 1 1 2
Amortization of actuarial loss 18 10 35 21
Net periodic cost/(benefit) 20 13 40 26
Cash contributions to qualified pension plan     0  
OPEB [Member]
       
Net Periodic Cost/(Benefit) [Abstract]        
Service cost 0 0 1 1
Interest cost 4 4 8 8
Amortization of prior service cost/(credit) (9) (11) (18) (22)
Amortization of actuarial loss 4 4 7 7
Net periodic cost/(benefit) $ (1) $ (3) $ (2) $ (6)