CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) $ in Thousands	Common Stock	Treasury Stock	Additional Paid-In Capital	Retained Earnings	Total
BALANCE at Dec. 31, 2021	$ 411	$ (150,580)	$ 327,061	$ 628,774	$ 805,666
BALANCE (in shares) at Dec. 31, 2021	41,123,365
BALANCE (in shares) at Dec. 31, 2021		(5,032,311)
Increase (Decrease) in Stockholders' Equity
Net income				86,762	86,762
Issuance of Stock:
Issuance of restricted stock & performance stock		$ 1,232	2,312		3,544
Issuance of restricted stock & performance stock (in shares)		38,863
Shares received in lieu of tax withholding on vested restricted stock		$ (1,399)			(1,399)
Shares received in lieu of tax withholding on vested restricted stock (in shares)		(15,348)
Stock-based compensation			2,605		2,605
Dividends				(4,673)	(4,673)
Share repurchase		$ (14,097)			(14,097)
Share repurchase (in shares)		(161,614)
BALANCE at Mar. 31, 2022	$ 411	$ (164,844)	331,978	710,863	878,408
BALANCE (in shares) at Mar. 31, 2022	41,123,365
BALANCE (in shares) at Mar. 31, 2022		(5,170,410)
BALANCE at Dec. 31, 2021	$ 411	$ (150,580)	327,061	628,774	805,666
BALANCE (in shares) at Dec. 31, 2021	41,123,365
BALANCE (in shares) at Dec. 31, 2021		(5,032,311)
Increase (Decrease) in Stockholders' Equity
Net income					190,523
BALANCE at Sep. 30, 2022	$ 411	$ (185,574)	331,710	804,585	951,132
BALANCE (in shares) at Sep. 30, 2022	41,123,365
BALANCE (in shares) at Sep. 30, 2022		(5,349,349)
BALANCE at Mar. 31, 2022	$ 411	$ (164,844)	331,978	710,863	878,408
BALANCE (in shares) at Mar. 31, 2022	41,123,365
BALANCE (in shares) at Mar. 31, 2022		(5,170,410)
Increase (Decrease) in Stockholders' Equity
Net income				42,246	42,246
Issuance of Stock:
Issuance of restricted stock & performance stock		$ 2,425	(2,425)
Issuance of restricted stock & performance stock (in shares)		75,092
Shares received in lieu of tax withholding on vested restricted stock		$ (1,848)			(1,848)
Shares received in lieu of tax withholding on vested restricted stock (in shares)		(20,658)
Stock-based compensation			1,822		1,822
Dividends				(5,026)	(5,026)
Share repurchase		$ (18,757)			(18,757)
Share repurchase (in shares)		(226,689)
BALANCE at Jun. 30, 2022	$ 411	$ (183,024)	331,375	748,083	896,845
BALANCE (in shares) at Jun. 30, 2022	41,123,365
BALANCE (in shares) at Jun. 30, 2022		(5,342,665)
Increase (Decrease) in Stockholders' Equity
Net income				61,515	61,515
Issuance of Stock:
Issuance of shares for options exercised		$ 1,023	(79)		944
Issuance of shares for options exercised (in shares)		29,862
Stock-based compensation			414		414
Dividends				(5,013)	(5,013)
Share repurchase		$ (3,573)			(3,573)
Share repurchase (in shares)		(36,546)
BALANCE at Sep. 30, 2022	$ 411	$ (185,574)	331,710	804,585	951,132
BALANCE (in shares) at Sep. 30, 2022	41,123,365
BALANCE (in shares) at Sep. 30, 2022		(5,349,349)
BALANCE at Dec. 31, 2022	$ 411	$ (187,212)	332,080	854,644	$ 999,923
BALANCE (in shares) at Dec. 31, 2022	41,123,365				41,123,365
BALANCE (in shares) at Dec. 31, 2022		(5,362,224)			5,362,224
Increase (Decrease) in Stockholders' Equity
Net income				57,216	$ 57,216
Issuance of Stock:
Issuance of shares for options exercised		$ 36	(18)		18
Issuance of shares for options exercised (in shares)		1,000
Issuance of restricted stock & performance stock		$ 1,131	3,384		4,515
Issuance of restricted stock & performance stock (in shares)		31,960
Shares received in lieu of tax withholding on vested restricted stock		$ (1,798)			(1,798)
Shares received in lieu of tax withholding on vested restricted stock (in shares)		(12,728)
Stock-based compensation			3,438		3,438
Dividends				(6,254)	(6,254)
Share repurchase		$ (3,568)			(3,568)
Share repurchase (in shares)		(29,400)
BALANCE at Mar. 31, 2023	$ 411	$ (191,411)	338,884	905,606	1,053,490
BALANCE (in shares) at Mar. 31, 2023	41,123,365
BALANCE (in shares) at Mar. 31, 2023		(5,371,392)
BALANCE at Dec. 31, 2022	$ 411	$ (187,212)	332,080	854,644	$ 999,923
BALANCE (in shares) at Dec. 31, 2022	41,123,365				41,123,365
BALANCE (in shares) at Dec. 31, 2022		(5,362,224)			5,362,224
Increase (Decrease) in Stockholders' Equity
Net income					$ 231,817
BALANCE at Sep. 30, 2023	$ 411	$ (197,085)	338,830	1,065,006	$ 1,207,162
BALANCE (in shares) at Sep. 30, 2023	41,123,365				41,123,365
BALANCE (in shares) at Sep. 30, 2023		(5,363,300)			5,363,300
BALANCE at Mar. 31, 2023	$ 411	$ (191,411)	338,884	905,606	$ 1,053,490
BALANCE (in shares) at Mar. 31, 2023	41,123,365
BALANCE (in shares) at Mar. 31, 2023		(5,371,392)
Increase (Decrease) in Stockholders' Equity
Net income				69,476	69,476
Issuance of Stock:
Issuance of restricted stock & performance stock		$ 2,220	(2,220)
Issuance of restricted stock & performance stock (in shares)		61,505
Shares received in lieu of tax withholding on vested restricted stock		$ (2,891)			(2,891)
Shares received in lieu of tax withholding on vested restricted stock (in shares)		(19,739)
Stock-based compensation			1,749		1,749
Dividends				(7,152)	(7,152)
Share repurchase		$ (3,208)			(3,208)
Share repurchase (in shares)		(24,000)
BALANCE at Jun. 30, 2023	$ 411	$ (195,290)	338,413	967,930	1,111,464
BALANCE (in shares) at Jun. 30, 2023	41,123,365
BALANCE (in shares) at Jun. 30, 2023		(5,353,626)
Increase (Decrease) in Stockholders' Equity
Net income				105,125	105,125
Issuance of Stock:
Issuance of restricted stock & performance stock		$ 28	(28)
Issuance of restricted stock & performance stock (in shares)		761
Shares received in lieu of tax withholding on vested restricted stock		$ (36)			(36)
Shares received in lieu of tax withholding on vested restricted stock (in shares)		(185)
Stock-based compensation			445		445
Dividends				(8,049)	(8,049)
Share repurchase		$ (1,787)			(1,787)
Share repurchase (in shares)		(10,250)
BALANCE at Sep. 30, 2023	$ 411	$ (197,085)	$ 338,830	$ 1,065,006	$ 1,207,162
BALANCE (in shares) at Sep. 30, 2023	41,123,365				41,123,365
BALANCE (in shares) at Sep. 30, 2023		(5,363,300)			5,363,300