Condensed Consolidated Statements of Stockholders' Equity (Unaudited) - USD ($) shares in Thousands, $ in Thousands	Common Stock Outstanding [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Treasury Stock [Member]	Total
Balance (in shares) at Dec. 31, 2019	7,446			30
Balance at Dec. 31, 2019	$ 74	$ 30,952	$ 131,552	$ (587)	$ 161,991
Share-based compensation (in shares)	28			0
Share-based compensation	$ 0	537	0	$ 0	537
Net share settlement of restricted stock units (in shares)	(11)			0
Net share settlement of restricted stock units	$ 0	(560)	0	$ 0	(560)
Net income	$ 0	0	3,891	$ 0	3,891
Exercise of stock options (in shares)	20			0
Exercise of stock options	$ 1	415	0	$ 0	416
Balance (in shares) at Mar. 31, 2020	7,483			30
Balance at Mar. 31, 2020	$ 75	31,344	135,443	$ (587)	166,275
Balance (in shares) at Dec. 31, 2019	7,446			30
Balance at Dec. 31, 2019	$ 74	30,952	131,552	$ (587)	161,991
Net income					6,209
Balance (in shares) at Jun. 30, 2020	7,495			30
Balance at Jun. 30, 2020	$ 75	31,963	137,761	$ (587)	169,212
Balance (in shares) at Mar. 31, 2020	7,483			30
Balance at Mar. 31, 2020	$ 75	31,344	135,443	$ (587)	166,275
Share-based compensation (in shares)	6			0
Share-based compensation	$ 0	561	0	$ 0	561
Net share settlement of restricted stock units (in shares)	0			0
Net share settlement of restricted stock units	$ 0	(1)	0	$ 0	(1)
Net income	$ 0	0	2,318	$ 0	2,318
Exercise of stock options (in shares)	6			0
Exercise of stock options	$ 0	59	0	$ 0	59
Balance (in shares) at Jun. 30, 2020	7,495			30
Balance at Jun. 30, 2020	$ 75	31,963	137,761	$ (587)	169,212
Balance (in shares) at Dec. 31, 2020	7,500			30
Balance at Dec. 31, 2020	$ 75	32,484	144,921	$ (587)	176,893
Share-based compensation (in shares)	34			0
Share-based compensation	$ 0	501	0	$ 0	501
Net share settlement of restricted stock units (in shares)	(14)			0
Net share settlement of restricted stock units	$ 0	(738)	0	$ 0	(738)
Net income	$ 0	0	4,163	$ 0	4,163
Balance (in shares) at Mar. 31, 2021	7,520			30
Balance at Mar. 31, 2021	$ 75	32,247	149,084	$ (587)	180,819
Balance (in shares) at Dec. 31, 2020	7,500			30
Balance at Dec. 31, 2020	$ 75	32,484	144,921	$ (587)	176,893
Net income					8,878
Balance (in shares) at Jun. 30, 2021	7,531			30
Balance at Jun. 30, 2021	$ 75	33,027	153,799	$ (587)	186,314
Balance (in shares) at Mar. 31, 2021	7,520			30
Balance at Mar. 31, 2021	$ 75	32,247	149,084	$ (587)	180,819
Share-based compensation	0	620	0	0	620
Net share settlement of restricted stock units	0	(2)	0	0	(2)
Net income	$ 0	0	4,715	$ 0	4,715
Exercise of stock options (in shares)	7			0
Exercise of stock options	$ 0	162	0	$ 0	162
Balance (in shares) at Jun. 30, 2021	7,531			30
Balance at Jun. 30, 2021	$ 75	$ 33,027	$ 153,799	$ (587)	$ 186,314