CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) $ in Thousands	Cumulative Effect, Period of Adoption, Adjustment [Member] Retained Earnings	Cumulative Effect, Period of Adoption, Adjustment [Member]	Common Stock	Treasury Stock	Additional Paid-In Capital	Retained Earnings	Total
BALANCE at Dec. 31, 2019			$ 411	$ (103,960)	$ 320,168	$ 368,685	$ 585,304
BALANCE (in shares) at Dec. 31, 2019			41,123,365
BALANCE (in shares) at Dec. 31, 2019				(4,465,448)
Increase (Decrease) in Stockholders' Equity
Net income						17,716	17,716
Issuance of Stock:
Issuance of restricted stock & performance stock				$ 1,054	801		1,855
Issuance of restricted stock & performance stock (in shares)				43,902
Shares received in lieu of tax withholding payment on vested restricted stock				$ (622)			(622)
Shares received in lieu of tax withholding payment on vested restricted stock (in shares)				(14,722)
Stock-based compensation					2,134		2,134
Dividends						(3,844)	(3,844)
Share repurchase				$ (8,985)			(8,985)
Share repurchase (in shares)				(237,359)
BALANCE at Mar. 31, 2020	$ (515)	$ (515)	$ 411	$ (112,513)	323,103	382,042	593,043
BALANCE (in shares) at Mar. 31, 2020			41,123,365
BALANCE (in shares) at Mar. 31, 2020				(4,673,627)
BALANCE at Dec. 31, 2020			$ 411	$ (129,243)	322,451	502,810	$ 696,429
BALANCE (in shares) at Dec. 31, 2020			41,123,365				41,123,365
BALANCE (in shares) at Dec. 31, 2020				(4,935,186)			4,935,186
Increase (Decrease) in Stockholders' Equity
Net income						26,491	$ 26,491
Issuance of Stock:
Issuance of shares for options exercised				$ 1,616	(211)		1,405
Issuance of shares for options exercised (in shares)				61,454
Issuance of restricted stock & performance stock				$ 777	1,431		2,208
Issuance of restricted stock & performance stock (in shares)				29,544
Shares received in lieu of tax withholding payment on vested restricted stock				$ (854)			(854)
Shares received in lieu of tax withholding payment on vested restricted stock (in shares)				(11,424)
Stock-based compensation					2,472		2,472
Dividends						(4,163)	(4,163)
Share repurchase				$ (885)			(885)
Share repurchase (in shares)				(13,250)
BALANCE at Mar. 31, 2021			$ 411	$ (128,589)	$ 326,143	$ 525,138	$ 723,103
BALANCE (in shares) at Mar. 31, 2021			41,123,365				41,123,365
BALANCE (in shares) at Mar. 31, 2021				(4,868,862)			4,868,862