Investment securities (Details 1) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2022	Dec. 31, 2021
Less Than 12 Months, Fair Value	$ 265,200	$ 224,680
Less Than 12 Months, Unrealized Losses	20,541	4,548
12 Months Or More, Fair Value	46,284	28,817
12 Months Or More, Unrealized Losses	4,675	988
Total, Fair Value	311,484	253,497
Total, Unrealized Losses	25,216	5,536
Mortgage-backed securities
Less Than 12 Months, Fair Value	146,319	131,483
Less Than 12 Months, Unrealized Losses	8,509	2,477
12 Months Or More, Fair Value	21,727	19,632
12 Months Or More, Unrealized Losses	1,392	542
Total, Fair Value	168,046	151,115
Total, Unrealized Losses	9,901	3,019
State and political subdivisions
Less Than 12 Months, Fair Value	106,097	80,076
Less Than 12 Months, Unrealized Losses	11,285	1,981
12 Months Or More, Fair Value	16,608	5,922
12 Months Or More, Unrealized Losses	3,093	276
Total, Fair Value	122,705	85,998
Total, Unrealized Losses	14,378	2,257
US Treasury Securities [Member]
Less Than 12 Months, Fair Value	10,369	7,889
Less Than 12 Months, Unrealized Losses	565	75
12 Months Or More, Fair Value	0	0
12 Months Or More, Unrealized Losses	0	0
Total, Fair Value	10,369	7,889
Total, Unrealized Losses	565	75
U.S. Government Sponsored Enterprises [Member]
Less Than 12 Months, Fair Value	2,415	5,232
Less Than 12 Months, Unrealized Losses	182	15
12 Months Or More, Fair Value	7,949	3,263
12 Months Or More, Unrealized Losses	190	170
Total, Fair Value	10,364	8,495
Total, Unrealized Losses	$ 372	$ 185