BENEFIT PLANS (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Pension Benefits [Member]
Net periodic benefit cost [Abstract]
Service cost	$ 831	$ 882	$ 2,493	$ 2,647
Interest cost	1,375	1,318	4,124	3,953
Expected return on plan assets	(3,042)	(2,980)	(9,127)	(8,941)
Amortization of unrecognized net loss	366	(77)	1,099	(230)
Amortization of prior service cost	2	1	6	4
Net periodic benefit income	(468)	(856)	(1,405)	(2,567)
Post-retirement Benefits [Member]
Net periodic benefit cost [Abstract]
Service cost	0	0	0	0
Interest cost	22	26	65	76
Expected return on plan assets	0	0	0	0
Amortization of unrecognized net loss	(3)	(2)	(10)	(5)
Amortization of prior service cost	(45)	(45)	(134)	(134)
Net periodic benefit income	$ (26)	$ (21)	$ (79)	$ (63)