Supplemental Retirement Plan and Related Post Retirement Benefits - Summary of the Components of Net Periodic Cost (Details) $ in Thousands |
3 Months Ended | 6 Months Ended | ||
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Jun. 30, 2018
USD ($)
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Jul. 01, 2017
USD ($)
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Jun. 30, 2018
USD ($)
retirement_plan
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Jul. 01, 2017
USD ($)
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| Retirement Benefits [Abstract] | ||||
| Number of non-qualified supplemental retirement defined benefit plans | retirement_plan | 2 | |||
| SERP | ||||
| Defined Benefit Plan Disclosure | ||||
| Service Cost | $ 50 | $ 46 | $ 100 | $ 92 |
| Interest Cost | 225 | 224 | 450 | 448 |
| Amortization of Prior Service Cost | 97 | 97 | 194 | 194 |
| Amortization of Net Actuarial Losses | 157 | 93 | 314 | 186 |
| Net Periodic Cost | 529 | 460 | 1,058 | 920 |
| SERP | SERP Medical | ||||
| Defined Benefit Plan Disclosure | ||||
| Service Cost | 4 | 2 | 8 | 4 |
| Interest Cost | 12 | 10 | 23 | 20 |
| Amortization of Prior Service Cost | 4 | 5 | 8 | 8 |
| Amortization of Net Actuarial Losses | 15 | 6 | 29 | 15 |
| Net Periodic Cost | $ 35 | $ 23 | $ 68 | $ 47 |
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- Definition Number of non-qualified supplemental retirement defined benefit plans. No definition available.
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- References No definition available.
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- Definition Amount of gain (loss) recognized in net periodic benefit (cost) credit of defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of prior service cost (credit) recognized in net periodic benefit cost (credit) of defined benefit plan. 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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- Definition Amount of cost recognized for passage of time related to defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of net periodic benefit cost (credit) for defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of cost for actuarial present value of benefits attributed to service rendered by employee for defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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- Details
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