Condensed Consolidated Statements of Shareholders' Equity (Unaudited) - USD ($) $ in Thousands	Total	Common Stock [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income (Loss) [Member]
Balance at Dec. 31, 2021	$ 732,021	$ 108,610	$ 623,465	$ (54)
Balance, Shares at Dec. 31, 2021		24,260,000
Net income	18,793		18,793
Share-based compensation	1,760	$ 1,760
Common stock issued under stock Plans, net of shares withheld for employee taxes, Shares		75,000
Taxes paid related to net share settlement of stock awards	(3,605)	$ (3,605)
Dividends accrued of $0.465, $0.465, $0.465, $0.455, $0.455 and $0.455 per share for three months ended March 31, 2023, June 30,2023, September 30, 2023 and three months ended March 31, 2022, June 30, 2022, September 30, 2022	(11,084)		(11,084)
Other comprehensive income (loss)	3			3
Balance at Mar. 31, 2022	737,888	$ 106,765	631,174	(51)
Balance, Shares at Mar. 31, 2022		24,335,000
Balance at Dec. 31, 2021	732,021	$ 108,610	623,465	(54)
Balance, Shares at Dec. 31, 2021		24,260,000
Net income	75,497
Balance at Sep. 30, 2022	773,068	$ 107,463	665,530	75
Balance, Shares at Sep. 30, 2022		24,382,000
Balance at Mar. 31, 2022	737,888	$ 106,765	631,174	(51)
Balance, Shares at Mar. 31, 2022		24,335,000
Net income	26,137		26,137
Share-based compensation	1,652	$ 1,652
Common stock issued under stock Plans, net of shares withheld for employee taxes, Shares		43,000
Taxes paid related to net share settlement of stock awards	(2,523)	$ (2,523)
Dividends accrued of $0.465, $0.465, $0.465, $0.455, $0.455 and $0.455 per share for three months ended March 31, 2023, June 30,2023, September 30, 2023 and three months ended March 31, 2022, June 30, 2022, September 30, 2022	(11,181)		(11,181)
Other comprehensive income (loss)	61			61
Balance at Jun. 30, 2022	752,034	$ 105,894	646,130	10
Balance, Shares at Jun. 30, 2022		24,378,000
Net income	30,567		30,567
Share-based compensation	1,694	$ 1,694
Common stock issued under stock Plans, net of shares withheld for employee taxes, Shares		4,000
Taxes paid related to net share settlement of stock awards	(125)	$ (125)
Dividends accrued of $0.465, $0.465, $0.465, $0.455, $0.455 and $0.455 per share for three months ended March 31, 2023, June 30,2023, September 30, 2023 and three months ended March 31, 2022, June 30, 2022, September 30, 2022	(11,167)		(11,167)
Other comprehensive income (loss)	65			65
Balance at Sep. 30, 2022	773,068	$ 107,463	665,530	75
Balance, Shares at Sep. 30, 2022		24,382,000
Balance at Dec. 31, 2022	$ 803,945	$ 110,080	693,943	(78)
Balance, Shares at Dec. 31, 2022	24,388,000	24,388,000
Net income	$ 71,657		71,657
Share-based compensation	1,493	$ 1,493
Common stock issued under stock Plans, net of shares withheld for employee taxes, Shares		78,000
Taxes paid related to net share settlement of stock awards	(6,086)	$ (6,086)
Dividends accrued of $0.465, $0.465, $0.465, $0.455, $0.455 and $0.455 per share for three months ended March 31, 2023, June 30,2023, September 30, 2023 and three months ended March 31, 2022, June 30, 2022, September 30, 2022	(11,453)		(11,453)
Other comprehensive income (loss)	(18)			(18)
Balance at Mar. 31, 2023	859,538	$ 105,487	754,147	(96)
Balance, Shares at Mar. 31, 2023		24,466,000
Balance at Dec. 31, 2022	$ 803,945	$ 110,080	693,943	(78)
Balance, Shares at Dec. 31, 2022	24,388,000	24,388,000
Net income	$ 142,605
Balance at Sep. 30, 2023	$ 911,372	$ 109,253	802,161	(42)
Balance, Shares at Sep. 30, 2023	24,489,000	24,489,000
Balance at Mar. 31, 2023	$ 859,538	$ 105,487	754,147	(96)
Balance, Shares at Mar. 31, 2023		24,466,000
Net income	30,582		30,582
Share-based compensation	1,889	$ 1,889
Common stock issued under stock Plans, net of shares withheld for employee taxes, Shares		19,000
Taxes paid related to net share settlement of stock awards	(14)	$ (14)
Dividends accrued of $0.465, $0.465, $0.465, $0.455, $0.455 and $0.455 per share for three months ended March 31, 2023, June 30,2023, September 30, 2023 and three months ended March 31, 2022, June 30, 2022, September 30, 2022	(11,469)		(11,469)
Other comprehensive income (loss)	43			43
Balance at Jun. 30, 2023	880,569	$ 107,362	773,260	(53)
Balance, Shares at Jun. 30, 2023		24,485,000
Net income	40,366		40,366
Share-based compensation	1,891	$ 1,891
Common stock issued under stock Plans, net of shares withheld for employee taxes, Shares		4,000
Dividends accrued of $0.465, $0.465, $0.465, $0.455, $0.455 and $0.455 per share for three months ended March 31, 2023, June 30,2023, September 30, 2023 and three months ended March 31, 2022, June 30, 2022, September 30, 2022	(11,465)		(11,465)
Other comprehensive income (loss)	11			11
Balance at Sep. 30, 2023	$ 911,372	$ 109,253	$ 802,161	$ (42)
Balance, Shares at Sep. 30, 2023	24,489,000	24,489,000