COMPONENTS OF QUARTERLY AND YEAR TO DATE NET PERIODIC BENEFIT COSTS (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Qualified Pension Plan
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost, benefits earned during the period	$ 0	$ 0	$ 0	$ 0
Interest cost on projected benefit obligation	379	385	1,136	1,154
Expected return on plan assets	(554)	(826)	(1,661)	(2,478)
Amortization of unrecognized transition obligation	0	0	0	0
Amortization of unrecognized prior service cost	0	0	0	0
Amortization of unrecognized net loss	49	43	147	130
Net periodic pension benefit	(126)	(398)	(378)	(1,194)
Supplemental Pension Plan
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost, benefits earned during the period	0	0	0	0
Interest cost on projected benefit obligation	13	12	39	36
Expected return on plan assets	0	0	0	0
Amortization of unrecognized prior service cost	0	0	0	0
Amortization of unrecognized net loss	1	1	3	5
Net periodic pension benefit	14	13	42	41
Postretirement Plan, Medical and Life
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost, benefits earned during the period	0	0	0	0
Interest cost on projected benefit obligation	4	4	10	11
Expected return on plan assets	0	0	0	0
Amortization of unrecognized prior service cost	(55)	(55)	(165)	(165)
Amortization of unrecognized net loss	22	28	68	83
Net periodic pension benefit	$ (29)	$ (23)	$ (87)	$ (71)