Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Total	Preferred Stock	Common Stock	Additional Paid-In Capital	Retained Earnings
Beginning balance (in shares) at Dec. 31, 2016		0	16,108,893
Beginning balance at Dec. 31, 2016	$ 264,670	$ 0	$ 161	$ 177,061	$ 87,448
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock under employee benefit plans (in shares)			226,986
Issuance of common stock under employee benefit plans	98		$ 2	96
Deemed repurchased shares of common and restricted stock for tax withholding (in shares)			(68,065)
Deemed repurchased shares of common and restricted stock for tax withholding	(1,587)			(1,587)
Stock-based compensation	$ 5,104			5,104
Repurchased and retired shares of common stock (in shares)	0
Net income	$ 21,121				21,121
Ending balance (in shares) at Dec. 31, 2017		0	16,267,814
Ending balance at Dec. 31, 2017	289,406	$ 0	$ 163	180,674	108,569
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock under employee benefit plans (in shares)			223,059
Issuance of common stock under employee benefit plans	0		$ 2	(2)
Deemed repurchased shares of common and restricted stock for tax withholding (in shares)			(66,088)
Deemed repurchased shares of common and restricted stock for tax withholding	(1,823)		$ (1)	(1,822)
Stock-based compensation	$ 8,322			8,322
Repurchased and retired shares of common stock (in shares)	0
Net income	$ 25,639				25,639
Ending balance (in shares) at Dec. 31, 2018		0	16,424,785
Ending balance at Dec. 31, 2018	321,266	$ 0	$ 164	187,172	133,930
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock under employee benefit plans (in shares)			252,597
Issuance of common stock under employee benefit plans	$ 0		$ 3	(3)
Deemed repurchased shares of common and restricted stock for tax withholding (in shares)	(1,416,304)		(83,214)
Deemed repurchased shares of common and restricted stock for tax withholding	$ (2,510)		$ (1)	(2,509)
Stock-based compensation	$ 5,960			5,960
Repurchased and retired shares of common stock (in shares)	(1,416,304)		(1,416,304)
Repurchased and retired shares of common stock	$ (37,996)		$ (14)		(37,982)
Net income	10,013				10,013
Ending balance (in shares) at Dec. 31, 2019		0	15,177,864
Ending balance at Dec. 31, 2019	$ 296,733	$ 0	$ 152	$ 190,620	$ 105,961