EMPLOYEE BENEFIT PLANS - Schedule of Fair Value of Plan Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	$ 81,899	$ 67,967	$ 0
Other Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	80,805	67,047
Other Pension Plan | Quoted Prices in Active Markets for Identical Items (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	651	744
Other Pension Plan | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	80,154	66,303
Other Pension Plan | Cash
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	651	744
Other Pension Plan | Cash | Quoted Prices in Active Markets for Identical Items (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	651	744
Other Pension Plan | Equity Index
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	2,785	2,014
Other Pension Plan | Equity Index | Quoted Prices in Active Markets for Identical Items (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	0	0
Other Pension Plan | Equity Index | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	2,785	2,014
Other Pension Plan | Diversified Growth Fund
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	17,296	11,637
Other Pension Plan | Diversified Growth Fund | Quoted Prices in Active Markets for Identical Items (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	0	0
Other Pension Plan | Diversified Growth Fund | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	17,296	11,637
Other Pension Plan | Global Absolute Return Fund
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	6,534	5,821
Other Pension Plan | Global Absolute Return Fund | Quoted Prices in Active Markets for Identical Items (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	0	0
Other Pension Plan | Global Absolute Return Fund | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	6,534	5,821
Other Pension Plan | Cash Fund
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	5,315	7,921
Other Pension Plan | Cash Fund | Quoted Prices in Active Markets for Identical Items (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	0	0
Other Pension Plan | Cash Fund | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	5,315	7,921
Other Pension Plan | United Kingdom | Equity Securities
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	17,809	13,927
Other Pension Plan | United Kingdom | Equity Securities | Quoted Prices in Active Markets for Identical Items (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	0	0
Other Pension Plan | United Kingdom | Equity Securities | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	17,809	13,927
Other Pension Plan | United Kingdom | Fixed Income Securities
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	6,494	5,454
Other Pension Plan | United Kingdom | Fixed Income Securities | Quoted Prices in Active Markets for Identical Items (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	0	0
Other Pension Plan | United Kingdom | Fixed Income Securities | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	6,494	5,454
Other Pension Plan | United Kingdom | Government Index Linked Securities
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	8,934	7,825
Other Pension Plan | United Kingdom | Government Index Linked Securities | Quoted Prices in Active Markets for Identical Items (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	0	0
Other Pension Plan | United Kingdom | Government Index Linked Securities | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	8,934	7,825
Other Pension Plan | United States | Equity Index
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	4,370	3,453
Other Pension Plan | United States | Equity Index | Quoted Prices in Active Markets for Identical Items (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	0	0
Other Pension Plan | United States | Equity Index | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	4,370	3,453
Other Pension Plan | European | Equity Index
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	4,378	3,421
Other Pension Plan | European | Equity Index | Quoted Prices in Active Markets for Identical Items (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	0	0
Other Pension Plan | European | Equity Index | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	4,378	3,421
Other Pension Plan | Pacific Rim | Equity Index
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	3,506	2,645
Other Pension Plan | Pacific Rim | Equity Index | Quoted Prices in Active Markets for Identical Items (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	0	0
Other Pension Plan | Pacific Rim | Equity Index | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	3,506	2,645
Other Pension Plan | JAPAN | Equity Index
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	2,733	2,185
Other Pension Plan | JAPAN | Equity Index | Quoted Prices in Active Markets for Identical Items (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	0	0
Other Pension Plan | JAPAN | Equity Index | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	$ 2,733	$ 2,185