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Effect of One-Percentage Point Change in Assumed Healthcare Cost Trend Rates (Detail) (USD $)
In Millions, unless otherwise specified |
12 Months Ended |
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Dec. 31, 2012
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| Defined Benefit Plan Disclosure [Line Items] | |
| Effect of 1-percentage point increase on total service and interest cost components | $ 0.2 |
| Effect of 1-percentage point increase on accumulated postretirement benefit obligation | 2.7 |
| Effect of 1-percentage point decrease on total service and interest cost components | (0.2) |
| Effect of 1-percentage point decrease on accumulated postretirement benefit obligation | $ (2.3) |
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- Details
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- Definition
Amount of 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
Amount of 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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