CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) $ in Thousands	Common Stock	Treasury Stock	Additional Paid-In Capital	Retained Earnings	Total
BALANCE at Dec. 31, 2020	$ 411	$ (129,243)	$ 322,451	$ 502,810	$ 696,429
BALANCE (in shares) at Dec. 31, 2020	41,123,365
BALANCE (in shares) at Dec. 31, 2020		(4,935,186)
Increase (Decrease) in Stockholders' Equity
Net income				143,348	143,348
Issuance of Stock:
Issuance of shares for options exercised		$ 5,399	235		5,634
Issuance of shares for options exercised (in shares)		195,724
Issuance of restricted stock & performance stock		$ 2,681	(473)		2,208
Issuance of restricted stock & performance stock (in shares)		101,360
Shares received in lieu of tax withholding on vested stock		$ (2,363)			(2,363)
Shares received in lieu of tax withholding on vested stock (in shares)		(31,413)
Stock-based compensation			4,848		4,848
Dividends				(17,384)	(17,384)
Share repurchase		$ (27,054)			(27,054)
Share repurchase (in shares)		(362,796)
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				245,947	245,947
Issuance of Stock:
Issuance of shares for options exercised		$ 1,174	(88)		1,086
Issuance of shares for options exercised (in shares)		34,187
Issuance of restricted stock & performance stock		$ 3,657	(113)		3,544
Issuance of restricted stock & performance stock (in shares)		113,955
Shares received in lieu of tax withholding on vested stock		$ (3,247)			(3,247)
Shares received in lieu of tax withholding on vested stock (in shares)		(36,006)
Stock-based compensation			5,220		5,220
Dividends				(20,077)	(20,077)
Share repurchase		$ (38,216)			(38,216)
Share repurchase (in shares)		(442,049)
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				323,398	$ 323,398
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		$ 3,398	1,117		4,515
Issuance of restricted stock & performance stock (in shares)		94,729
Shares received in lieu of tax withholding on vested stock		$ (4,725)			(4,725)
Shares received in lieu of tax withholding on vested stock (in shares)		(32,652)
Stock-based compensation			6,383		6,383
Dividends				(30,379)	(30,379)
Share repurchase		$ (21,304)			(21,304)
Share repurchase (in shares)		(139,478)
BALANCE at Dec. 31, 2023	$ 411	$ (209,807)	$ 339,562	$ 1,147,663	$ 1,277,829
BALANCE (in shares) at Dec. 31, 2023	41,123,365				41,123,365
BALANCE (in shares) at Dec. 31, 2023		(5,438,625)			5,438,625