Employee Retirement Plans - Multiemployer plans (Details) - NCT - USD ($) $ in Thousands |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2017 |
Dec. 31, 2016 |
Dec. 31, 2015 |
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| Employee Retirement Plans | |||
| Contribution to NCT (as a percent of total plan contribution) | 1.00% | ||
| Contributions by employer | $ 2,319 | $ 1,926 | $ 1,730 |
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- Definition Percentage of Multiemployer plan contributions to NCT to the total contributions to the plan. No definition available.
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- Definition Amount of contributions made to multiemployer plans by the employer. A multiemployer plan is a pension or postretirement benefit plan to which two or more unrelated employers contribute where assets contributed by one participating employer may be used to provide benefits to employees of other participating employers. 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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- Details
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