Investment Securities - Gross unrealized losses (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Investment securities available-for-sale
Unrealized losses less than 12 months	$ (532)	$ (313)
Fair value less than 12 months	89,457	46,067
Unrealized losses over 12 months	(13)	(162)
Fair value over 12 months	3,667	36,019
Total Unrealized losses	(545)	(475)
Total Fair value	93,124	82,086
U.S. treasury and government agencies
Investment securities available-for-sale
Unrealized losses less than 12 months	(10)	(5)
Fair value less than 12 months	4,509	1,740
Unrealized losses over 12 months	(9)	(10)
Fair value over 12 months	1,309	9,990
Total Unrealized losses	(19)	(15)
Total Fair value	5,818	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		11,959
Unrealized losses over 12 months		(21)
Fair value over 12 months		5,798
Total Unrealized losses		(161)
Total Fair value		17,757
Mortgage backed securities - Residential agency
Investment securities available-for-sale
Unrealized losses less than 12 months		(52)
Fair value less than 12 months		17,131
Unrealized losses over 12 months		(79)
Fair value over 12 months		14,036
Total Unrealized losses		(131)
Total Fair value		31,167
Mortgage backed securities - Commercial
Investment securities available-for-sale
Unrealized losses less than 12 months	(432)	(116)
Fair value less than 12 months	68,494	15,235
Unrealized losses over 12 months	(4)	(52)
Fair value over 12 months	2,356	6,195
Total Unrealized losses	(436)	(168)
Total Fair value	70,850	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	(90)
Fair value less than 12 months	16,454
Total Unrealized losses	(90)
Total Fair value	$ 16,454