EMPLOYEE BENEFIT PLANS (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2020 USD ($) plan	Jun. 30, 2019 USD ($)	Dec. 31, 2019 USD ($)
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost	$ 34	$ 32
Interest cost	13	20
Amortization of prior service cost	38	36
Amortization of gain	(26)	(22)
Net periodic benefit cost	$ 59	$ 66
Defined Benefit Plan Disclosure [Line Items]
Number of savings plan | plan	2
Benefit obligation	$ 1,123		$ 1,076
Deferred compensation liability	3,044		1,982
Related rabbi trust assets	3,046		1,982
Maximum
Defined Benefit Plan Disclosure [Line Items]
Historical cash payments for retirement medical plan claims per year	$ 100
Postretirement Medical Plan
Defined Benefit Plan Disclosure [Line Items]
Number of defined benefit plans | plan	2
Defined Benefit Pension Plan | Chemogas
Defined Benefit Plan Disclosure [Line Items]
Benefit obligation	$ 596		$ 596