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Health Care Cost Trend Rates (Detail)
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12 Months Ended | ||
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Dec. 31, 2014
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Dec. 31, 2013
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Dec. 31, 2012
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| Defined Benefit Plan Disclosure [Line Items] | |||
| Healthcare cost trend rate assumed for next year | 6.50%us-gaap_DefinedBenefitPlanHealthCareCostTrendRateAssumedForNextFiscalYear | 6.50%us-gaap_DefinedBenefitPlanHealthCareCostTrendRateAssumedForNextFiscalYear | 7.00%us-gaap_DefinedBenefitPlanHealthCareCostTrendRateAssumedForNextFiscalYear |
| Rate to which cost trend rate gradually declines | 4.75%us-gaap_DefinedBenefitPlanUltimateHealthCareCostTrendRate | 4.75%us-gaap_DefinedBenefitPlanUltimateHealthCareCostTrendRate | 5.00%us-gaap_DefinedBenefitPlanUltimateHealthCareCostTrendRate |
| Year the rate reaches the level it is assumed to remain thereafter | 2022 | 2020 | 2016 |
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- Details
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- Definition
The assumed health care cost trend rate for the next year used to measure the expected cost of benefits covered by the plan (gross eligible charges). This is based upon the annual rate of change in the cost of health care benefits currently provided by the postretirement benefit plan, due to factors other than changes in the composition of the plan population by age and dependency status. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
The ultimate trend rate for health care costs. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Year the ultimate health care cost trend rate is expected to be reached, in CCYY format. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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