Retirement Plans and Related Post Retirement Benefits - Assumptions Used to Calculate the Post Retirement Benefit Obligation (Detail) |
Dec. 31, 2016 |
Dec. 31, 2015 |
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| SERP | ||
| Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] | ||
| Discount Rate | 4.20% | 4.45% |
| SERP Medical | ||
| Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] | ||
| Discount Rate | 4.20% | 4.45% |
| Minimum | SERP | ||
| Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] | ||
| Future Average Compensation Increases | 3.00% | 3.00% |
| Maximum | SERP | ||
| Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] | ||
| Future Average Compensation Increases | 5.00% | 5.00% |
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- Definition The interest rate used to adjust for the time value of money for the plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Expected rate of compensation increases (for pay-related plans). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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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