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Retirement Benefit Obligations - Additional Information (Detail) | 6 Months Ended
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Jun. 30, 2018 USD ($)
Pension Plans |
Defined Benefit Plan Disclosure [Line Items] |
Contributions to benefit plan | $ 1,200,000
Expected additional benefit payments for the remainder of 2018 | 15,000,000
Other Postretirement Benefit Plans, Defined Benefit |
Defined Benefit Plan Disclosure [Line Items] |
Contributions to benefit plan | 2,000,000
Supplemental Employee Retirement Plans, Defined Benefit |
Defined Benefit Plan Disclosure [Line Items] |
Expected additional benefit payments for the remainder of 2018 | 333,500
Benefit payments under SERP Plan | $ 65,700

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- Definition Amount of payment to participant of defined benefit plan which decreases benefit obligation. For pension plan, payment includes, but is not limited to, pension benefits and death benefits. For other postretirement plan, payment includes, but is not limited to, prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a)(6) -URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e1928-114920 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 60 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=6414203&loc=d3e39716-114964 + Details
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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. + References No definition available. + Details
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