Pensions and Other Benefits - Actuarial Assumptions Used (Detail) |
12 Months Ended | ||
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Dec. 31, 2017 |
Dec. 31, 2016 |
Dec. 31, 2015 |
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Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items] | |||
Discount rate | 3.80% | 4.02% | 4.22% |
Projected future salary increases | 2.75% | 2.75% | 3.00% |
Health care cost trend rate | 7.00% | 7.00% | 7.00% |
Discount rate | 4.02% | 4.22% | 4.09% |
Expected rate of return on fund assets | 7.75% | 7.75% | 7.75% |
Projected future salary increases | 2.75% | 3.00% | 3.00% |
Health care cost trend rate change | 0.50% | 0.50% | |
Ultimate rate | 5.00% | 5.00% | |
Health care cost trend rate previously assumed | 6.50% | ||
Heath care cost trend rate previously assumed two years prior | 7.00% |
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- Definition Defined Benefit Plan, Health Care Cost Trend Rate Assumed for Next Fiscal Year, Previous Assumptions No definition available.
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- Definition Defined Benefit Plan, Health Care Cost Trend Rate Change No definition available.
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- Definition Defined Benefit Plan, Health Care Cost Trent Rate Assumed for Next Fiscal Year, Previous Assumptions, Two Years Prior No definition available.
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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- Definition Weighted average rate for present value of future retirement benefits cash flows, used to determine benefit obligation of defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Weighted average rate increase of compensation, used to determine benefit obligation of defined benefit plan. Plan includes, but is not limited to, pay-related defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Weighted average rate for present value of future retirement benefits cash flows, used to determine net periodic benefit cost of defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Weighted average rate of return on plan assets, reflecting average rate of earnings expected on existing plan assets and expected contributions, used to determine net periodic benefit cost of defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Weighted average rate of compensation increase used to determine net periodic benefit cost of defined benefit plan. Plan includes, but is not limited to, pay-related defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Assumed rate, for next fiscal year, based on annual change in cost of health care cost benefits used to measure expected cost of benefits covered by defined benefit postretirement plan. Factors include, but are not limited to, estimate of health care inflation, change in health care utilization or delivery pattern, technological advances, and change in health status of participant. Excludes factors for change in composition of plan population by age and dependency status. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Ultimate trend rate for health care cost for defined benefit postretirement plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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