RETIREMENT AND POSTRETIREMENT PLANS (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Retirement Plans [Member] | BMP, Employee and Outside Director Retirement Plans [Member]
Net Periodic Benefit Cost [Abstract]
Service cost	$ 0	$ 0	$ 0	$ 0
Interest cost	291	329	583	658
Expected return on assets	(430)	(395)	(860)	(790)
Unrecognized past service liability	0	0	0	0
Amortization of unrealized loss (gain)	289	359	578	718
Net periodic cost	150	293	301	586
Retirement Plans [Member] | Employee Retirement Plan [Member]
Retirement and Postretirement Plans [Abstract]
Estimated employer contributions or benefit payments					$ 17
Contributions by employer	8		12
Retirement Plans [Member] | Outside Director Retirement Plan [Member]
Retirement and Postretirement Plans [Abstract]
Estimated employer contributions or benefit payments					226
Contributions by employer	56		112
Retirement Plans [Member] | BMP Retirement Plan [Member]
Retirement and Postretirement Plans [Abstract]
Estimated employer contributions or benefit payments					564
Contributions by employer	137		274
Lump-sum distribution for retired participant	$ 56		$ 1,255
Distribution of common stock (in shares)	3,038		52,634
Shares returned to Treasury Stock (in shares)	1,090		28,365
Component held by ESOP	$ 56		$ 998
Benefit held by defined contribution plan			257
Tax benefit from market valuation adjustment on distribution of ESOP shares	8		293
Other Postretirement Plan [Member] | Postretirement Plan [Member]
Net Periodic Benefit Cost [Abstract]
Service cost	0	0	0	0
Interest cost	13	14	27	28
Expected return on assets	0	0	0	0
Unrecognized past service liability	(2)	(2)	(4)	(4)
Amortization of unrealized loss (gain)	0	(1)	0	(2)
Net periodic cost	11	$ 11	23	$ 22
Retirement and Postretirement Plans [Abstract]
Estimated employer contributions or benefit payments					$ 121
Contributions by employer	$ 33		$ 50