CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS' EQUITY - USD ($) $ in Thousands	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Total
Balance at Dec. 31, 2019	$ 18,036	$ 140,492	$ 146,696	$ 958	$ 306,182
Balance (in shares) at Dec. 31, 2019	18,036,115
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	$ 0	0	7,083	0	7,083
Cash dividends, common	0	0	(541)	0	(541)
Other comprehensive income (loss)	0	0	0	13,939	13,939
Exercise of employee stock options and vesting of restricted stock units	$ 20	(103)	0	0	(83)
Exercise of employee stock options and vesting of restricted stock units (in shares)	19,899
Stock based compensation	$ 0	310	0	0	310
Balance at Mar. 31, 2020	$ 18,056	140,699	153,238	14,897	326,890
Balance (in shares) at Mar. 31, 2020	18,056,014
Balance at Dec. 31, 2020	$ 18,076	141,112	189,521	21,339	$ 370,048
Balance (in shares) at Dec. 31, 2020	18,076,364				18,076,364
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	$ 0	0	15,160	0	$ 15,160
Cash dividends, common	0	0	(904)	0	(904)
Other comprehensive income (loss)	0	0	0	(9,131)	(9,131)
Exercise of employee stock options and vesting of restricted stock units	$ 20	(126)	0	0	(106)
Exercise of employee stock options and vesting of restricted stock units (in shares)	20,049
Stock based compensation	$ 0	390	0	0	390
Repurchases of common stock	$ (43)	(743)	0	0	(786)
Repurchases of common stock (in shares)	(43,184)
Balance at Mar. 31, 2021	$ 18,053	$ 140,633	$ 203,777	$ 12,208	$ 374,671
Balance (in shares) at Mar. 31, 2021	18,053,229				18,053,229