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Benefit Plans - Narrative (Detail) - USD ($) $ in Thousands |  | 9 Months Ended
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Mar. 08, 2018 | Sep. 30, 2018
Defined Benefit Plan Disclosure [Line Items] |  |
Minimum eligibility for full-time employees, age |  | 21 years
Number of highest-paid consecutive years for benefits |  | 5 years
Amount contributed to pension plan | $ 205 |
Minimum |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Period of service credit by employee |  | 1 year

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- Definition Number of highest paid consecutive periods of service for calculation of average compensation related to benefits. + References No definition available. + Details
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