INCOME TAXES (Details) - USD ($)		12 Months Ended
	Dec. 22, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Current:
Federal		$ 2,594,000	$ 6,330,000	$ 3,668,000
State		417,000	638,000	216,000
Total current		3,011,000	6,968,000	3,884,000
Deferred expense/(benefit):
Federal		942,000	(2,177,000)	595,000
State		382,000	(387,000)	179,000
Remeasurement of deferred tax assets	$ 2,900,000	2,927,000	0	0
Total deferred		4,251,000	(2,564,000)	774,000
Income tax expense		$ 7,262,000	$ 4,404,000	$ 4,658,000
Reconciliation of income tax expense [Abstract]
Statutory federal tax rate		34.00%	34.00%	34.00%
Tax computed at statutory rate		$ 5,006,000	$ 4,907,000	$ 4,791,000
Tax-exempt income		(663,000)	(511,000)	(441,000)
831(b) premium adjustment		(269,000)	(368,000)	0
Dividend exclusion		(8,000)	(5,000)	(41,000)
State taxes, net of Federal impact		201,000	165,000	238,000
Nondeductible interest expense		8,000	9,000	8,000
Remeasurement of deferred tax assets		2,927,000	0	0
Other items, net		60,000	207,000	103,000
Income tax expense		$ 7,262,000	$ 4,404,000	$ 4,658,000
Effective tax rate		49.40%	30.50%	33.10%
Deferred tax assets:
Allowance for loan losses		$ 5,396,000	$ 5,405,000
Accrual for employee benefit plans		186,000	337,000
Depreciation		86,000	2,119,000
Deferred compensation and directors' fees		872,000	1,195,000
Purchase accounting adjustment – deposits		7,000	21,000
Purchase accounting adjustment – loans		35,000	44,000
Purchase accounting adjustment – fixed assets		149,000	221,000
Gain on deemed sale of securities		567,000	798,000
Net unrealized losses on securities available for sale		1,169,000	2,643,000
Accounting for defined benefit pension and other benefit plans		2,370,000	4,091,000
Nonaccrued interest		544,000	944,000
Accrued expense		868,000	854,000
Other items, net		160,000	286,000
Total gross deferred tax assets		12,409,000	18,958,000
Deferred tax liabilities:
Deferred loan fees and costs		676,000	940,000
Prepaid pension		3,023,000	3,956,000
Discount accretion		239,000	342,000
Core deposit intangible		1,026,000	1,460,000
REIT dividend		844,000	0
Other		101,000	152,000
Total gross deferred tax liabilities		5,909,000	6,850,000
Net deferred tax asset		6,500,000	12,108,000
Unrecognized tax benefits		0	0	$ 0
Accrued interest or penalties related to uncertain tax positions		$ 0	$ 0	$ 0