5. INVESTMENT SECURITIES (Details 1) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2018	Dec. 31, 2017
Less than 12 months, Estimated Fair Value	$ 138,152	$ 122,552
Less than 12 months, Unrealized Loss	(2,427)	(1,181)
12 months or more, Estimated Fair Value	107,661	53,912
12 months or more, Unrealized Loss	(4,105)	(1,208)
Total Estimated Fair Value	245,813	176,464
Total Unrealized Loss	(6,532)	(2,389)
US Government Agencies and Sponsored Agencies
Less than 12 months, Estimated Fair Value	127,137	119,455
Less than 12 months, Unrealized Loss	(2,321)	(1,148)
12 months or more, Estimated Fair Value	100,217	49,258
12 months or more, Unrealized Loss	(3,767)	(1,123)
Total Estimated Fair Value	227,354	168,713
Total Unrealized Loss	(6,088)	(2,271)
Obligations of states and political subdivisions
Less than 12 months, Estimated Fair Value	5,554	1,130
Less than 12 months, Unrealized Loss	(98)	(9)
12 months or more, Estimated Fair Value	5,518	4,654
12 months or more, Unrealized Loss	(272)	(85)
Total Estimated Fair Value	11,072	5,784
Total Unrealized Loss	(370)	(94)
Corporate Bonds
Less than 12 months, Estimated Fair Value	498	1,967
Less than 12 months, Unrealized Loss	(2)	(24)
12 months or more, Estimated Fair Value	1,926	0
12 months or more, Unrealized Loss	(66)	0
Total Estimated Fair Value	2,424	1,967
Total Unrealized Loss	(68)	$ (24)
US Treasury securities
Less than 12 months, Estimated Fair Value	4,963
Less than 12 months, Unrealized Loss	(6)
12 months or more, Estimated Fair Value	0
12 months or more, Unrealized Loss	0
Total Estimated Fair Value	4,963
Total Unrealized Loss	$ (6)