Employees Retirement Plans - Pension expense (Details) $ in Thousands |
12 Months Ended | ||
|---|---|---|---|
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Dec. 31, 2020
USD ($)
item
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Dec. 31, 2019
USD ($)
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Dec. 31, 2018
USD ($)
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| Employee Retirement Plans | |||
| Number of regional multi-employer pension plans in which the entity participates | item | 44 | ||
| Defined contribution plans | $ 10,251 | $ 10,015 | $ 7,595 |
| Multi-employer plans | 11,754 | 13,241 | 11,224 |
| Total expense related to participation in retirement plans | $ 22,005 | $ 23,256 | $ 18,819 |
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- Definition Amount of expense related to multiemployer retirement plans. No definition available.
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- Definition Represents the number of regional multi-employer pension plans in which the entity participates. No definition available.
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- Definition The amount of expense related to Company's participation in retirement plans. No definition available.
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- References No definition available.
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- Definition Amount of cost for defined contribution plan. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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