CONDENSED CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS' EQUITY (UNAUDITED) - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock	Additional Paid-In Capital	Accumulated Other Comprehensive Income	Retained Earnings	Treasury Stock
Balance (in shares) at Dec. 31, 2021		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	41,781				41,781
Share-based compensation (in shares)		18
Share-based compensation	2,275		2,275
Net shares repurchased for employee taxes (in shares)		(8)
Net shares repurchased for employee taxes	(1,459)		(1,459)
Treasury stock from stock repurchases	(10,000)					(10,000)
Treasury stock retired from stock repurchases (in shares)		(51)
Treasury stock retired from stock repurchases	0				(10,000)	10,000
Other comprehensive income	16			16
Cash dividends declared to stockholders	(19,063)				(19,063)
Balance (in shares) at Mar. 31, 2022		11,553
Balance at Mar. 31, 2022	216,024	$ 12	12,834	127	203,051	0
Balance (in shares) at Dec. 31, 2021		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	$ 117,050
Options exercised by directors (in shares)	0
Other comprehensive income	$ 279
Balance (in shares) at Sep. 30, 2022		10,929
Balance at Sep. 30, 2022	150,522	$ 11	18,617	391	131,503	0
Balance (in shares) at Mar. 31, 2022		11,553
Balance at Mar. 31, 2022	216,024	$ 12	12,834	127	203,051	0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	39,113				39,113
Share-based compensation (in shares)		1
Share-based compensation	2,865		2,865
Net shares repurchased for employee taxes	(20)		(20)
Treasury stock from stock repurchases	(90,038)					(90,038)
Treasury stock retired from stock repurchases (in shares)		(535)
Treasury stock retired from stock repurchases	(1)	$ (1)			(90,038)	90,038
Stock Repurchases, not yet settled	(20,010)		(15,679)		(4,331)
Other comprehensive income	141			141
Cash dividends declared to stockholders	(18,598)				(18,598)
Balance (in shares) at Jun. 30, 2022		11,019
Balance at Jun. 30, 2022	129,476	$ 11	0	268	129,197	0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	36,155				36,155
Share-based compensation (in shares)		1
Share-based compensation	2,963		2,963
Net shares repurchased for employee taxes	(25)		(25)
Treasury stock from stock repurchases	(20,010)					(20,010)
Treasury stock retired from stock repurchases (in shares)		(91)
Treasury stock retired from stock repurchases	0				(20,010)	20,010
Settlement of accelerated share repurchase agreement	20,010		15,679		4,331
Other comprehensive income	123			123
Cash dividends declared to stockholders	(18,170)				(18,170)
Balance (in shares) at Sep. 30, 2022		10,929
Balance at Sep. 30, 2022	$ 150,522	$ 11	18,617	391	131,503	0
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)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	39,968				39,968
Share-based compensation (in shares)		69
Share-based compensation	606		606
Options exercised by directors (in shares)		4
Options exercised by directors	105		105
Net shares repurchased for employee taxes (in shares)		(30)
Net shares repurchased for employee taxes	(3,236)		(3,236)
Treasury stock from stock repurchases	(3,602)					(3,602)
Treasury stock retired from stock repurchases (in shares)		(84)
Treasury stock retired from stock repurchases	0				(10,000)	10,000
Other comprehensive income	9			9
Cash dividends declared to stockholders	(17,994)				(17,994)
Balance (in shares) at Mar. 31, 2023		10,887
Balance at Mar. 31, 2023	$ 170,900	$ 11	19,030	33	151,826	0
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)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	$ 93,380
Options exercised by directors (in shares)	4
Other comprehensive income	$ 116
Balance (in shares) at Sep. 30, 2023	10,892	10,892
Balance at Sep. 30, 2023	$ 193,035	$ 11	24,107	141	168,776	0
Balance (in shares) at Mar. 31, 2023		10,887
Balance at Mar. 31, 2023	170,900	$ 11	19,030	33	151,826	0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	30,280				30,280
Share-based compensation (in shares)		2
Share-based compensation	2,514		2,514
Net shares repurchased for employee taxes	(2)		(2)
Other comprehensive income	90			90
Cash dividends declared to stockholders	(18,221)				(18,221)
Balance (in shares) at Jun. 30, 2023		10,889
Balance at Jun. 30, 2023	185,561	$ 11	21,542	123	163,885	0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	23,131				23,131
Share-based compensation (in shares)		4
Share-based compensation	2,675		2,675
Net shares repurchased for employee taxes (in shares)		(1)
Net shares repurchased for employee taxes	(110)		(110)
Other comprehensive income	18			18
Cash dividends declared to stockholders	$ (18,240)				(18,240)
Balance (in shares) at Sep. 30, 2023	10,892	10,892
Balance at Sep. 30, 2023	$ 193,035	$ 11	$ 24,107	$ 141	$ 168,776	$ 0