Condensed Consolidated Statements of Stockholders' Equity (Unaudited) - USD ($) $ in Thousands	Total	Common Stock [Member]	Treasury Stock [Member]	Additional Paid-in Capital [Member]	Accumulated Other Comprehensive Loss [Member]	Retained Earnings [Member]
BALANCE at Dec. 31, 2022	$ 725,845	$ 894	$ (301,624)	$ 684,183	$ (5,447)	$ 347,839
BALANCE, shares at Dec. 31, 2022		89,396,000
BALANCE, shares at Dec. 31, 2022			(22,221,000)
Net income	89,157					89,157
Foreign currency translation	23				23
Unrealized loss on investments, net of tax	(197)				(197)
Treasury stock purchased	(2,729)		$ (2,729)
Treasury stock purchased, shares			(221,000)
Treasury stock acquired upon sale of asset	(22,086)		$ (22,086)
Treasury stock acquired upon sale of asset, shares			(1,800,000)
Share-based compensation expense	4,315			4,315
Common stock issued	(1,896)	$ 6	$ (2,209)	307
Common stock issued, shares		620,000	(165,000)
BALANCE at Jun. 30, 2023	792,432	$ 900	$ (328,648)	688,805	(5,621)	436,996
BALANCE, shares at Jun. 30, 2023		90,016,000
BALANCE, shares at Jun. 30, 2023			(24,407,000)
BALANCE at Mar. 31, 2023	761,172	$ 899	$ (304,648)	686,719	(4,121)	382,323
BALANCE, shares at Mar. 31, 2023		89,924,000
BALANCE, shares at Mar. 31, 2023			(22,446,000)
Net income	54,673					54,673
Foreign currency translation	(3)				(3)
Unrealized loss on investments, net of tax	(1,497)				(1,497)
Treasury stock purchased	(1,914)		$ (1,914)
Treasury stock purchased, shares			(161,000)
Treasury stock acquired upon sale of asset	(22,086)		$ (22,086)
Treasury stock acquired upon sale of asset, shares			(1,800,000)
Share-based compensation expense	2,021			2,021
Common stock issued	66	$ 1		65
Common stock issued, shares		92,000
BALANCE at Jun. 30, 2023	792,432	$ 900	$ (328,648)	688,805	(5,621)	436,996
BALANCE, shares at Jun. 30, 2023		90,016,000
BALANCE, shares at Jun. 30, 2023			(24,407,000)
BALANCE at Dec. 31, 2023	$ 841,421	$ 903	$ (334,220)	694,798	(666)	480,606
BALANCE, shares at Dec. 31, 2023	90,270,306	90,270,000
BALANCE, shares at Dec. 31, 2023	(24,725,767)		(24,726,000)
Net income	$ 77,871					77,871
Foreign currency translation	(39)				(39)
Unrealized loss on investments, net of tax	(1,016)				(1,016)
Dividends to shareholders	(14,871)					(14,871)
Treasury stock purchased	(6,769)		$ (6,769)
Treasury stock purchased, shares			(385,000)
Share-based compensation expense	4,557			4,557
Common stock issued	(1,630)	$ 7	$ (3,435)	1,798
Common stock issued, shares		708,000	(193,000)
BALANCE at Jun. 30, 2024	$ 899,524	$ 910	$ (344,424)	701,153	(1,721)	543,606
BALANCE, shares at Jun. 30, 2024	90,977,866	90,978,000
BALANCE, shares at Jun. 30, 2024	(25,304,436)		(25,304,000)
BALANCE at Mar. 31, 2024	$ 866,106	$ 909	$ (344,424)	698,619	(1,620)	512,622
BALANCE, shares at Mar. 31, 2024		90,907,000
BALANCE, shares at Mar. 31, 2024			(25,304,000)
Net income	38,429					38,429
Foreign currency translation	(8)				(8)
Unrealized loss on investments, net of tax	(93)				(93)
Dividends to shareholders	(7,445)					(7,445)
Share-based compensation expense	2,250			2,250
Common stock issued	285	$ 1		284
Common stock issued, shares		71,000
BALANCE at Jun. 30, 2024	$ 899,524	$ 910	$ (344,424)	$ 701,153	$ (1,721)	$ 543,606
BALANCE, shares at Jun. 30, 2024	90,977,866	90,978,000
BALANCE, shares at Jun. 30, 2024	(25,304,436)		(25,304,000)