EMPLOYEE BENEFITS - Amounts in Accumulated Other Comprehensive Income (Loss) Recognized in Net Periodic Benefit Cost (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Defined Benefit Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Net loss	$ 1,827	$ 1,512	$ 1,312
Prior service (credit) cost	(14)	(14)	(14)
Total amount in other comprehensive income recognized in net periodic benefit cost, before tax	1,813	1,498
Deferred tax expense	(381)	(315)
Accumulated other comprehensive income, net of tax	1,432	1,183
Defined Benefit Pension Plan Acquired
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Net loss	0	0	0
Prior service (credit) cost	0	0	0
Total amount in other comprehensive income recognized in net periodic benefit cost, before tax	0	0
Deferred tax expense	0	0
Accumulated other comprehensive income, net of tax	0	0
Restoration Plan
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Net loss	559	677	301
Prior service (credit) cost	6	7	$ 6
Total amount in other comprehensive income recognized in net periodic benefit cost, before tax	565	684
Deferred tax expense	(118)	(144)
Accumulated other comprehensive income, net of tax	$ 447	$ 540