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PENSION AND POST-RETIREMENT PLANS - MULTI-EMPLOYER DEFINED CONTRIBUTION PLANS (Details) - Multi-employer defined contribution pension plans $ in Millions | 12 Months Ended
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Dec. 31, 2018 USD ($) plan | Dec. 31, 2017 USD ($) | Dec. 31, 2016 USD ($)
Defined Contribution Plans |  |  |
Number of Multiemployer Plans | plan | 6 |  |
Employer contributions | $ | $ 4.8 | $ 5.0 | $ 5.3

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- Definition Represents the number of multiemployer plans in which the entity participates. + References No definition available. + Details
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- Definition Amount of cost for defined contribution plan. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 70 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=49170846&loc=d3e28014-114942 + Details
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