| **Benefit Plans**                                                 | 6 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |
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| **Compensation and Retirement Disclosure [Abstract]**             | Â                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
| Pension and Other Postretirement Benefits Disclosure [Text Block] | Benefit PlansThe components of net periodic cost (benefit) are presented in the following table.Net Periodic Cost (Benefit)Periods ended June 30Three Months Six Months(In millions)2011 2010 2011 2010Pension cost       Service cost$3 $4 $7 $8Interest cost on projected benefit obligation36 36 73 74Expected return on plan assets(43) (40) (86) (81)Amortization of net actuarial loss6 6 12 12Net periodic pension cost$2 $6 $6 $13        Postretirement benefit       Service cost$— $— $— $1Interest cost on projected benefit obligation1 2 2 4Amortization of prior service credit(4) (4) (9) (8)Amortization of net actuarial (gain) loss(1) 1 — 1Net periodic postretirement benefit$(4) $(1) $(7) $(2) |

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| - Definition
The entire disclosure for pension and other postretirement benefits.
+ References
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