CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) $ in Thousands	Common Stock	Capital in Excess of Par Value	Retained Earnings Cumulative Effect, Period of Adoption, Adjustment [Member]	Retained Earnings	Accumulated Other Comprehensive (Loss) Income Cumulative Effect, Period of Adoption, Adjustment [Member]	Accumulated Other Comprehensive (Loss) Income	Cumulative Effect, Period of Adoption, Adjustment [Member]	Total
Balance at Dec. 31, 2018	$ 21,454			$ 947,711		$ (18,746)		$ 950,419
Balance (in shares) at Dec. 31, 2018	214,544,000
Increase (Decrease) in Stockholders' Equity
Stock issued for stock incentive plans, net	$ 66	$ 8,564						8,630
Stock issued for stock incentive plans, net (in shares)	667,000
Stock purchased and retired	$ (77)	(8,564)		1,280				(7,361)
Stock purchased and retired (in shares)	(788,000)
Net income (loss)				(87,111)				(87,111)
Pension adjustment, net of taxes						(2,298)		(2,298)
Foreign currency translation						553		553
Dividends declared				(32,231)				(32,231)
Balance at Dec. 31, 2019	$ 21,443			832,113		(23,223)		830,333
Balance (in shares) at Dec. 31, 2019	214,423,000
Increase (Decrease) in Stockholders' Equity
Adoption of accounting standard (Note 1)			$ 2,464		$ (2,732)		$ (268)
Stock issued for stock incentive plans, net	$ 71	8,664						8,735
Stock issued for stock incentive plans, net (in shares)	716,000
Stock purchased and retired	$ (19)	(8,664)		7,857				(826)
Stock purchased and retired (in shares)	(188,000)
Net income (loss)				(212,192)				(212,192)
Pension adjustment, net of taxes						5,727		5,727
Foreign currency translation						(210)		(210)
Balance at Dec. 31, 2020	$ 21,495			627,778		(17,706)		$ 631,567
Balance (in shares) at Dec. 31, 2020	214,951,000							214,951,093
Increase (Decrease) in Stockholders' Equity
Stock issued for stock incentive plans, net	$ 82	6,494						$ 6,576
Stock issued for stock incentive plans, net (in shares)	819,000
Stock purchased and retired	$ (14)	$ (6,494)		5,941				(567)
Stock purchased and retired (in shares)	(141,000)
Net income (loss)				7,217				7,217
Pension adjustment, net of taxes						(2,890)		(2,890)
Foreign currency translation						(112)		(112)
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