EMPLOYEE BENEFIT PLANS - Employee benefit plan amounts recognized in the Consolidated Balance Sheets and Consolidated Statements of Income (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Retirement Benefits [Abstract]
Service cost	$ 1,926	$ 1,545	$ 3,776	$ 3,295
Interest cost	607	689	1,207	1,389
Expected return on plan assets	(2,464)	(2,409)	(4,939)	(4,859)
Amortization of prior service cost	(102)	(106)	(202)	(206)
Defined Benefit Plan, Amortization of Gain (Loss)	559	426	1,084	901
Net periodic benefit cost (income)	$ 526	$ 145	$ 926	$ 520