CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) $ in Thousands	Common Stock	Capital in Excess of Par Value	Retained Earnings	Accumulated Other Comprehensive (Loss) Income	Total
Balance at Dec. 31, 2020	$ 21,495		$ 627,778	$ (17,706)	$ 631,567
Balance (in shares) at Dec. 31, 2020	214,951,000
Increase (Decrease) in Stockholders' Equity
Stock issued for stock incentive plans, net	$ 93	$ 1,446			1,539
Stock issued for stock incentive plans, net (in shares)	924,000
Stock purchased and retired	$ (14)	(1,446)	903		(557)
Stock purchased and retired (in shares)	(140,000)
Net income (loss)			(9,662)		(9,662)
Pension adjustment, net of taxes				153	153
Foreign currency translation				136	136
Balance at Mar. 31, 2021	$ 21,574		619,019	(17,417)	623,176
Balance (in shares) at Mar. 31, 2021	215,735,000
Balance at Dec. 31, 2021	$ 21,563		640,936	(20,708)	$ 641,791
Balance (in shares) at Dec. 31, 2021	215,629,000				215,628,716
Increase (Decrease) in Stockholders' Equity
Stock issued for stock incentive plans, net	$ 104	1,393			$ 1,497
Stock issued for stock incentive plans, net (in shares)	1,037,000
Stock purchased and retired	$ (19)	$ (1,393)	502		(910)
Stock purchased and retired (in shares)	(190,000)
Net income (loss)			15,079		15,079
Pension adjustment, net of taxes				195	195
Foreign currency translation				116	116
Balance at Mar. 31, 2022	$ 21,648		$ 656,517	$ (20,397)	$ 657,768
Balance (in shares) at Mar. 31, 2022	216,476,000				216,476,421