Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Common Stock [Member]	Additional Paid-In Capital [Member]	Retained Earnings [Member]	Total
Beginning balance at Dec. 31, 2018	$ 302	$ 595,037	$ 264,020	$ 859,359
Beginning balance, shares at Dec. 31, 2018	30,155,000
Issuance of common stock, net	$ 27	79,025		79,052
Issuance of common stock, net, shares	2,717,000
Repurchase of common stock	$ (1)	(1,438)		$ (1,439)
Repurchase of common stock, shares	(83,000)			(83,000)
Vesting of restricted stock units	$ 4	(4)
Vesting of restricted stock units, shares	430,000
Withholding of common stock upon vesting of restricted stock units	$ (1)	(3,582)		(3,583)
Withholding of common stock upon vesting of restricted stock units, shares	(152,000)
Stock-based compensation expense		15,316		15,316
Net income			112,994	112,994
Ending balance at Dec. 31, 2019	$ 331	684,354	377,014	$ 1,061,699
Ending balance, shares at Dec. 31, 2019	33,067,000
Repurchase of common stock, shares
Vesting of restricted stock units	$ 5	(5)
Vesting of restricted stock units, shares	454,000
Withholding of common stock upon vesting of restricted stock units	$ (2)	(5,098)		(5,100)
Withholding of common stock upon vesting of restricted stock units, shares	(170,000)
Stock-based compensation expense		18,334		18,334
Other		385		385
Net income			206,157	206,157
Ending balance at Dec. 31, 2020	$ 334	697,200	583,171	$ 1,280,705
Ending balance, shares at Dec. 31, 2020	33,351,000
Repurchase of common stock, shares
Vesting of restricted stock units and issuance of unrestricted common stock awards	$ 7	(7)
Vesting of restricted stock units and issuance of unrestricted common stock awards, shares	675,000
Withholding of common stock upon vesting of restricted stock units	$ (3)	(13,723)		(13,726)
Withholding of common stock upon vesting of restricted stock units, shares	(265,000)
Stock-based compensation expense		14,377		14,377
Cash dividends declared		158	(15,350)	(15,192)
Other		(160)		(160)
Net income			498,504	498,504
Ending balance at Dec. 31, 2021	$ 338	$ 697,845	$ 1,066,325	$ 1,764,508
Ending balance, shares at Dec. 31, 2021	33,761,000