v3.8.0.1
EMPLOYEE BENEFIT PLANS Narrative 3 (Details) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2017
Dec. 31, 2016
Pension Plan [Member]    
Defined Benefit Plan Disclosure [Line Items]    
Plan contributions $ 11,105 $ 15,601
Estimated future employer contributions in next fiscal year 11,200  
Other Postretirement Benefits Plan [Member]    
Defined Benefit Plan Disclosure [Line Items]    
Plan contributions 127 $ 169
Estimated future employer contributions in next fiscal year $ 400