Investment Securities - Gross unrealized losses (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Investment securities available-for-sale
Unrealized losses less than 12 months	$ (131)	$ (313)
Fair value less than 12 months	52,028	46,067
Unrealized losses over 12 months	(12)	(162)
Fair value over 12 months	3,914	36,019
Total Unrealized losses	(143)	(475)
Total Fair value	55,942	82,086
U. S. Treasury and agencies
Investment securities available-for-sale
Unrealized losses less than 12 months	(9)	(5)
Fair value less than 12 months	4,694	1,740
Unrealized losses over 12 months	(8)	(10)
Fair value over 12 months	1,309	9,990
Total Unrealized losses	(17)	(15)
Total Fair value	6,003	11,730
Obligations of state and political agencies
Investment securities available-for-sale
Unrealized losses less than 12 months		(140)
Fair value less than 12 months	590	11,959
Unrealized losses over 12 months		(21)
Fair value over 12 months		5,798
Total Unrealized losses		(161)
Total Fair value	590	17,757
Mortgage backed securities - Residential Agency
Investment securities available-for-sale
Unrealized losses less than 12 months	(45)	(52)
Fair value less than 12 months	15,481	17,131
Unrealized losses over 12 months		(79)
Fair value over 12 months		14,036
Total Unrealized losses	(45)	(131)
Total Fair value	15,481	31,167
Mortgage backed securities - Commercial
Investment securities available-for-sale
Unrealized losses less than 12 months	(48)	(116)
Fair value less than 12 months	25,292	15,235
Unrealized losses over 12 months	(4)	(52)
Fair value over 12 months	2,603	6,195
Total Unrealized losses	(52)	(168)
Total Fair value	27,895	21,430
Asset backed securities
Investment securities available-for-sale
Fair value less than 12 months		2
Fair value over 12 months	2
Total Fair value	2	$ 2
Corporate bonds
Investment securities available-for-sale
Unrealized losses less than 12 months	(29)
Fair value less than 12 months	5,971
Total Unrealized losses	(29)
Total Fair value	$ 5,971