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Effects of One Percent Change in Assumed Health Care Cost Trend (Detail) (U.S. Postretirement Medical Benefits, USD $)
In Millions, unless otherwise specified |
12 Months Ended |
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Dec. 31, 2011
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U.S. Postretirement Medical Benefits
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| Defined Benefit Plan Disclosure [Line Items] | |
| Effect on total of service cost and interest cost | $ 6 |
| Effect on postretirement benefit obligation | 61 |
| Effect on total of service cost and interest cost | (6) |
| Effect on postretirement benefit obligation | $ (65) |
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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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