Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Total	Capital Stock, Common	Additional Paid-in Capital	Retained Earnings	Treasury Stock
Balance at Dec. 31, 2019	$ 684,659	$ 907	$ 4,141	$ 826,666	$ (147,055)
Net income	13,238	0	0	13,238	0
Dividends on common stock, $0.02 per share	(1,628)	0	0	(1,628)	0
Repurchases of common stock	(12,278)	0	0	0	(12,278)
Stock-based compensation, net of tax	697	0	291	0	406
Balance at Mar. 31, 2020	684,688	907	4,432	838,276	(158,927)
Balance at Dec. 31, 2020	724,334	907	4,330	890,970	(171,873)
Net income	13,734	0	0	13,734	0
Dividends on common stock, $0.02 per share	(1,599)	0	0	(1,599)	0
Repurchases of common stock	(14,537)	0	0	0	(14,537)
Stock-based compensation, net of tax	485	0	146	0	339
Balance at Mar. 31, 2021	$ 722,417	$ 907	$ 4,476	$ 903,105	$ (186,071)