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Pension and Postretirement Benefit Plans - One-Percentage-Point Increase or Decrease in the Healthcare Cost Trend Rate (Detail) (Postretirement Plans [Member], USD $)
In Millions, unless otherwise specified |
12 Months Ended |
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Dec. 31, 2011
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Postretirement Plans [Member]
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| Defined Benefit Plan Disclosure [Line Items] | |
| Effect on total service and interest cost components, decrease | $ (17) |
| Effect on postretirement benefit obligation, decrease | (270) |
| Effect on total service and interest cost components, increase | 18 |
| Effect on postretirement benefit obligation, increase | $ 304 |
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- Details
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- Definition
The effect of a one-percentage-point decrease in the assumed health care cost trend rates on the accumulated postretirement benefit obligation for health care benefits. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
The effect of a one-percentage- point decrease in the assumed health care cost trend rates on the aggregate of the service and interest cost components of net periodic postretirement health care benefit costs. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
The effect of a one-percentage-point increase in the assumed health care cost trend rates on the accumulated postretirement benefit obligation for health care benefits. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
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- Definition
The effect of a one-percentage-point increase in the assumed health care cost trend rates on the aggregate of the service and interest cost components of net periodic postretirement health care benefit costs. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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