Securities (Details) $ in Thousands	6 Months Ended
Jun. 30, 2020 USD ($) security	Jun. 30, 2019 USD ($)	Dec. 31, 2019 USD ($) security
Securities available for sale
Securities available for sale, Percent	100.00%		100.00%
Available-for-sale Securities Reconciliation [Abstract]
Amortized Cost	$ 353,924		$ 351,069
Gross Unrealized Gains	12,557		4,564
Gross Unrealized (Losses)	(29)		(330)
Amortized Cost
Due in one year or less	49,005
Due after one year through five years	213,618
Due after five years through ten years	76,762
Due over ten years	14,539
Fair Value
Due in one year or less	49,249
Due after one year through five years	221,496
Due after five years through ten years	80,824
Due over ten years	14,883
Carrying value of investment securities pledged to collateralize short-term borrowings	366,452		$ 355,303
Debt Securities, Available-for-sale, Realized Gain (Loss) [Abstract]
Sales proceeds	313	$ 4,881
Gross realized gains	10	0
Gross realized losses	$ 0	$ 52
Less than 12 months
Number of securities \| security	15		77
Fair Value	$ 10,986		$ 45,813
Unrealized Loss	$ (22)		$ (255)
Percentage	0.20%		0.56%
12 months or more
Number of securities \| security	5		27
Fair Value	$ 621		$ 21,549
Unrealized Loss	$ (7)		$ (75)
Percentage	1.13%		0.35%
Total
Number of securities \| security	20		104
Fair Value	$ 11,607		$ 67,362
Unrealized Loss	$ (29)		$ (330)
Percentage	0.25%		0.49%
Collateralized Securities [Member]
Fair Value
Carrying value of investment securities pledged to collateralize short-term borrowings	$ 13,790
U.S. Treasury [Member]
Securities available for sale
Securities available for sale, Percent	43.59%		36.19%
Available-for-sale Securities Reconciliation [Abstract]
Amortized Cost	$ 153,525		$ 127,096
Gross Unrealized Gains	6,219		1,626
Gross Unrealized (Losses)	(2)		(137)
Fair Value
Carrying value of investment securities pledged to collateralize short-term borrowings	$ 159,742		$ 128,585
Less than 12 months
Number of securities \| security	2		11
Fair Value	$ 5,292		$ 27,932
Unrealized Loss	$ (2)		$ (136)
Percentage	0.04%		0.49%
12 months or more
Number of securities \| security	0		1
Fair Value	$ 0		$ 2,495
Unrealized Loss	$ 0		$ (1)
Percentage	0.00%		0.04%
Total
Number of securities \| security	2		12
Fair Value	$ 5,292		$ 30,427
Unrealized Loss	$ (2)		$ (137)
Percentage	0.04%		0.45%
Other securities [Member]
Securities available for sale
Securities available for sale, Percent	3.53%		4.29%
Available-for-sale Securities Reconciliation [Abstract]
Amortized Cost	$ 12,884		$ 15,287
Gross Unrealized Gains	49		0
Gross Unrealized (Losses)	(4)		(58)
Fair Value
Carrying value of investment securities pledged to collateralize short-term borrowings	$ 12,929		$ 15,229
Less than 12 months
Number of securities \| security	1		0
Fair Value	$ 2,616		$ 0
Unrealized Loss	$ (4)		$ 0
Percentage	0.15%		0.00%
12 months or more
Number of securities \| security	0		6
Fair Value	$ 0		$ 15,229
Unrealized Loss	$ 0		$ (58)
Percentage	0.00%		0.38%
Total
Number of securities \| security	1		6
Fair Value	$ 2,616		$ 15,229
Unrealized Loss	$ (4)		$ (58)
Percentage	0.15%		0.38%
State and political subdivisions [Member]
Securities available for sale
Securities available for sale, Percent	52.88%		59.52%
Available-for-sale Securities Reconciliation [Abstract]
Amortized Cost	$ 187,515		$ 208,686
Gross Unrealized Gains	6,289		2,938
Gross Unrealized (Losses)	(23)		(135)
Fair Value
Carrying value of investment securities pledged to collateralize short-term borrowings	$ 193,781		$ 211,489
Less than 12 months
Number of securities \| security	12		66
Fair Value	$ 3,078		$ 17,881
Unrealized Loss	$ (16)		$ (119)
Percentage	0.52%		0.67%
12 months or more
Number of securities \| security	5		20
Fair Value	$ 621		$ 3,825
Unrealized Loss	$ (7)		$ (16)
Percentage	1.13%		0.42%
Total
Number of securities \| security	17		86
Fair Value	$ 3,699		$ 21,706
Unrealized Loss	$ (23)		$ (135)
Percentage	0.62%		0.62%

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