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EMPLOYEE SAVINGS PLANS AND MULTI-EMPLOYER PENSION PLANS - Narrative (Details) $ in Millions	12 Months Ended
	Dec. 31, 2019 USD ($) employee	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Defined Contribution Plan Disclosure [Line Items]
Potential maximum contribution stated as a percentage of employee compensation	60.00%
Percent matched of employee contributions	100.00%
Percent of employee gross pay	5.00%
Defined contribution plan, cost \| $	$ 6.0	$ 5.9	$ 4.8
Non-Qualified Savings Plan
Defined Contribution Plan Disclosure [Line Items]
Maximum base compensation deferral percent	75.00%
Maximum annual bonus deferral percent	75.00%
Rabbi trust to fund the plan's obligation \| $	$ 2.1	$ 2.6
Unionized Employees Concentration Risk
Defined Contribution Plan Disclosure [Line Items]
Number of employees represented by labor unions \| employee	1,079
Percent of workforce represented by labor unions	34.00%
Collective Bargaining Agreements, Less Than One Year Expiration
Defined Contribution Plan Disclosure [Line Items]
Number of employees represented by labor unions \| employee	432
Percent of workforce represented by labor unions	13.60%