CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS' EQUITY - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock	Additional Paid-In Capital	Accumulated Other Comprehensive Income (Loss)	Retained Earnings	Treasury Stock
Balance (in shares) at Dec. 31, 2019		12,272
Balance at Dec. 31, 2019	$ 104,832	$ 12	$ 0	$ 25	$ 168,788	$ (63,993)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	102,859				102,859
Share-based compensation (in shares)		17
Share-based compensation	6,796		6,796
Options exercised by executives and directors (in shares)		28
Options exercised by executives and directors	$ 1,597		1,597
Net shares repurchased for taxes (in shares)	(6)	(6)
Net shares repurchased for taxes	$ (551)		(551)
Treasury stock from stock repurchases	(5,000)					(5,000)
Treasury stock retired from stock repurchases (in shares)		(489)
Treasury stock retired from stock repurchases	0				(63,993)	63,993
Other comprehensive income	16			16
Cash dividends declared to stockholders	(53,303)				(53,303)
Balance (in shares) at Dec. 31, 2020		11,822
Balance at Dec. 31, 2020	157,246	$ 12	7,842	41	154,351	(5,000)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	164,031				164,031
Share-based compensation (in shares)		55
Share-based compensation	$ 9,596		9,454		142
Options exercised by executives and directors (in shares)	29	29
Options exercised by executives and directors	$ 811		811
Net shares repurchased for taxes (in shares)	(22)	(28)
Net shares repurchased for taxes	$ (6,089)		(6,089)
Treasury stock from stock repurchases	(55,999)					(55,999)
Treasury stock retired from stock repurchases (in shares)		(284)
Treasury stock retired from stock repurchases	0				(60,999)	60,999
Other comprehensive income	70			70
Cash dividends declared to stockholders	$ (67,192)				(67,192)
Balance (in shares) at Dec. 31, 2021	11,594	11,594
Balance at Dec. 31, 2021	$ 202,474	$ 12	12,018	111	190,333	0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	143,568				143,568
Share-based compensation (in shares)		20
Share-based compensation	$ 11,053		11,053
Options exercised by executives and directors (in shares)	0
Net shares repurchased for taxes (in shares)	(9)	(9)
Net shares repurchased for taxes	$ (1,516)		(1,516)
Treasury stock from stock repurchases	(126,445)					(126,445)
Treasury stock retired from stock repurchases (in shares)		(677)
Treasury stock retired from stock repurchases	(1)	$ (1)			(120,047)	120,047
Other comprehensive income	(87)			(87)
Cash dividends declared to stockholders	$ (74,002)				(74,002)
Balance (in shares) at Dec. 31, 2022	10,928	10,928
Balance at Dec. 31, 2022	$ 155,044	$ 11	$ 21,555	$ 24	$ 139,852	$ (6,398)