Consolidated Statements of Stockholders' Equity (Unaudited) - USD ($) $ in Thousands	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	AOCI Attributable to Parent [Member]	Treasury Stock [Member]	Total
Balance (in shares) at Dec. 31, 2019	21,678,927				1,522,035
Balance at Dec. 31, 2019	$ 217	$ 105,934	$ 57,029	$ (4,007)	$ (11,032)	$ 148,141
Net income			3,174			3,174
Other comprehensive income (loss)				(1,518)		(1,518)
Issuance of common stock for stock options exercised (in shares)	19,141
Issuance of common stock for stock options exercised	$ 0	233				233
Vested restricted stock units (in shares)	4,074
Vested restricted stock units	$ 0	0				0
Stock-based compensation expense		779				779
Repurchase of common stock for net settlement of equity awards (in shares)					1,601
Repurchase of common stock for net settlement of equity awards					$ (57)	(57)
Common stock dividend paid			(1,917)			(1,917)
Balance (in shares) at Mar. 31, 2020	21,702,142				1,523,636
Balance at Mar. 31, 2020	$ 217	106,946	58,286	(5,525)	$ (11,089)	148,835
Balance (in shares) at Dec. 31, 2019	21,678,927				1,522,035
Balance at Dec. 31, 2019	$ 217	105,934	57,029	(4,007)	$ (11,032)	148,141
Net income						14,187
Other comprehensive income (loss)						998
Balance (in shares) at Sep. 30, 2020	21,819,924				1,531,166
Balance at Sep. 30, 2020	$ 218	109,640	65,457	(3,009)	$ (11,323)	160,983
Balance (in shares) at Mar. 31, 2020	21,702,142				1,523,636
Balance at Mar. 31, 2020	$ 217	106,946	58,286	(5,525)	$ (11,089)	148,835
Net income			3,500			3,500
Other comprehensive income (loss)				1,366		1,366
Issuance of common stock for stock options exercised (in shares)	3,000
Issuance of common stock for stock options exercised	$ 0	42				42
Vested restricted stock units (in shares)	192
Vested restricted stock units	$ 0	0				0
Stock-based compensation expense		803				803
Common stock dividend paid			(1,917)			(1,917)
Balance (in shares) at Jun. 30, 2020	21,705,334				1,523,636
Balance at Jun. 30, 2020	$ 217	107,791	59,869	(4,159)	$ (11,089)	152,629
Net income			7,513			7,513
Other comprehensive income (loss)				1,150		1,150
Issuance of common stock for stock options exercised (in shares)	92,014
Issuance of common stock for stock options exercised	$ 1	1,162				1,163
Vested restricted stock units (in shares)	22,576
Vested restricted stock units	$ 0	0				0
Stock-based compensation expense		687				687
Repurchase of common stock for net settlement of equity awards (in shares)					7,530
Repurchase of common stock for net settlement of equity awards					$ (234)	(234)
Common stock dividend paid			(1,925)			(1,925)
Balance (in shares) at Sep. 30, 2020	21,819,924				1,531,166
Balance at Sep. 30, 2020	$ 218	109,640	65,457	(3,009)	$ (11,323)	160,983
Balance (in shares) at Dec. 31, 2020	22,061,554				1,538,572
Balance at Dec. 31, 2020	$ 221	114,924	70,554	(1,525)	$ (11,602)	172,572
Net income			5,929			5,929
Other comprehensive income (loss)				(938)		(938)
Issuance of common stock for stock options exercised (in shares)	63,895
Issuance of common stock for stock options exercised	$ 0	1,385				1,385
Vested restricted stock units (in shares)	5,974
Vested restricted stock units	$ 0					0
Stock-based compensation expense		927				927
Repurchase of common stock for net settlement of equity awards (in shares)					2,241
Repurchase of common stock for net settlement of equity awards					$ (88)	(88)
Common stock dividend paid			(2,262)			(2,262)
Balance (in shares) at Mar. 31, 2021	22,131,423				1,540,813
Balance at Mar. 31, 2021	$ 221	117,236	74,221	(2,463)	$ (11,690)	177,525
Balance (in shares) at Dec. 31, 2020	22,061,554				1,538,572
Balance at Dec. 31, 2020	$ 221	114,924	70,554	(1,525)	$ (11,602)	172,572
Net income						20,732
Other comprehensive income (loss)						(1,111)
Balance (in shares) at Sep. 30, 2021	23,384,129				1,546,036
Balance at Sep. 30, 2021	$ 234	179,070	84,356	(2,636)	$ (11,976)	249,048
Balance (in shares) at Mar. 31, 2021	22,131,423				1,540,813
Balance at Mar. 31, 2021	$ 221	117,236	74,221	(2,463)	$ (11,690)	177,525
Net income			8,299			8,299
Other comprehensive income (loss)				220		220
Issuance of common stock for stock options exercised (in shares)	70,355
Issuance of common stock for stock options exercised	$ 1	1,186				1,187
Stock-based compensation expense		869				869
Common stock dividend paid			(2,267)			(2,267)
Balance (in shares) at Jun. 30, 2021	22,201,778				1,540,813
Balance at Jun. 30, 2021	$ 222	119,291	80,253	(2,243)	$ (11,690)	185,833
Net income			6,504			6,504
Other comprehensive income (loss)				(393)		(393)
Issuance of common stock for stock options exercised (in shares)	17,410
Issuance of common stock for stock options exercised	$ 0	299				299
Vested restricted stock units (in shares)	14,941
Vested restricted stock units	$ 0	0				0
Stock-based compensation expense		797				797
Repurchase of common stock for net settlement of equity awards (in shares)					5,223
Repurchase of common stock for net settlement of equity awards					$ (286)	(286)
Common stock dividend paid			(2,401)			(2,401)
Issuance of common stock (in shares)	1,150,000
Issuance of common stock	$ 12	58,683				58,695
Balance (in shares) at Sep. 30, 2021	23,384,129				1,546,036
Balance at Sep. 30, 2021	$ 234	$ 179,070	$ 84,356	$ (2,636)	$ (11,976)	$ 249,048