INCOME TAXES (Details) - USD ($)		12 Months Ended
	Dec. 22, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Current:
Federal		$ 1,732,000	$ 2,594,000	$ 6,330,000
State		124,000	417,000	638,000
Total current		1,856,000	3,011,000	6,968,000
Deferred expense/(benefit):
Federal		2,253,000	942,000	(2,177,000)
State		345,000	382,000	(387,000)
Remeasurement of deferred tax assets	$ (2,900,000)	445,000	(2,927,000)	0
Total deferred		2,153,000	4,251,000	(2,564,000)
Income tax expense		$ 4,009,000	$ 7,262,000	$ 4,404,000
Reconciliation of income tax expense [Abstract]
Statutory federal tax rate		21.00%	34.00%	34.00%
Tax computed at statutory rate		$ 4,963,000	$ 5,006,000	$ 4,907,000
Tax-exempt income		(430,000)	(663,000)	(511,000)
831(b) premium adjustment		(167,000)	(269,000)	(368,000)
Dividend exclusion		(7,000)	(8,000)	(5,000)
State taxes, net of Federal impact		262,000	201,000	165,000
Nondeductible interest expense		7,000	8,000	9,000
Remeasurement of deferred tax assets		(445,000)	2,927,000	0
Other items, net		(174,000)	60,000	207,000
Income tax expense		$ 4,009,000	$ 7,262,000	$ 4,404,000
Effective tax rate		17.00%	49.40%	30.50%
Deferred tax assets:
Allowance for loan losses		$ 4,834,000	$ 5,396,000
Accrual for employee benefit plans		136,000	186,000
Deferred Tax Liabilities, Property, Plant and Equipment		(93,000)
Depreciation			86,000
Deferred compensation and directors' fees		634,000	872,000
Purchase accounting adjustment – deposits		0	7,000
Purchase accounting adjustment – loans		7,000	35,000
Purchase accounting adjustment – fixed assets		149,000	149,000
Gain on deemed sale of securities		339,000	567,000
Net unrealized losses on securities available for sale		1,590,000	1,169,000
Accounting for defined benefit pension and other benefit plans		2,315,000	2,370,000
Nonaccrued interest		625,000	544,000
Accrued expense		200,000	868,000
Other items, net		153,000	160,000
Total gross deferred tax assets		10,889,000	12,409,000
Deferred tax liabilities:
Deferred loan fees and costs		640,000	676,000
Prepaid pension		3,141,000	3,023,000
Discount accretion		137,000	239,000
Core deposit intangible		1,101,000	1,026,000
REIT dividend		1,048,000	844,000
Other		109,000	101,000
Total gross deferred tax liabilities		6,176,000	5,909,000
Net deferred tax asset		4,713,000	6,500,000
Unrecognized tax benefits		0	0	$ 0
Accrued interest or penalties related to uncertain tax positions		$ 0	$ 0	$ 0