CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (Unaudited) - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock Shares [Member]	Treasury Stock-Common [Member]	Capital in Excess of Par Value [Member]	Retained Earnings [Member]	Non-Redeemable Preferred Stock [Member]
Balance at Dec. 31, 2018	$ 342,197	$ 3,128	$ (16,186)	$ 198,482	$ 153,773	$ 3,000
Balance, shares at Dec. 31, 2018		31,283	(2,438)
Net loss	(11,540)				(11,540)
Dividend accrued on redeemable preferred stock	(7,256)				(7,256)
Accretion of redeemable preferred stock	(496)				(496)
Stock-based compensation	612			612
Other	(690)		$ (546)	(144)
Other, Shares			(76)
Balance at Mar. 31, 2019	322,827	$ 3,128	$ (16,732)	198,950	134,481	3,000
Balance, shares at Mar. 31, 2019		31,283	(2,514)
Balance at Dec. 31, 2018	342,197	$ 3,128	$ (16,186)	198,482	153,773	3,000
Balance, shares at Dec. 31, 2018		31,283	(2,438)
Net loss	(4,909)
Balance at Jun. 30, 2019	322,058	$ 3,128	$ (16,732)	199,636	133,026	3,000
Balance, shares at Jun. 30, 2019		31,283	(2,514)
Balance at Mar. 31, 2019	322,827	$ 3,128	$ (16,732)	198,950	134,481	3,000
Balance, shares at Mar. 31, 2019		31,283	(2,514)
Net loss	6,631				6,631
Dividend accrued on redeemable preferred stock	(7,589)				(7,589)
Accretion of redeemable preferred stock	(497)				(497)
Stock-based compensation	686			686
Balance at Jun. 30, 2019	322,058	$ 3,128	$ (16,732)	199,636	133,026	3,000
Balance, shares at Jun. 30, 2019		31,283	(2,514)
Balance at Dec. 31, 2019	247,327	$ 3,128	$ (13,266)	196,833	57,632	3,000
Balance, shares at Dec. 31, 2019		31,283	(2,010)
Net loss	(19,452)				(19,452)
Dividend accrued on redeemable preferred stock	(8,307)				(8,307)
Accretion of redeemable preferred stock	(504)				(504)
Stock-based compensation	495			495
Other	(64)		$ 292	(356)
Other, Shares			30
Balance at Mar. 31, 2020	219,495	$ 3,128	$ (12,974)	196,972	29,369	3,000
Balance, shares at Mar. 31, 2020		31,283	(1,980)
Balance at Dec. 31, 2019	247,327	$ 3,128	$ (13,266)	196,833	57,632	3,000
Balance, shares at Dec. 31, 2019		31,283	(2,010)
Net loss	(19,817)
Balance at Jun. 30, 2020	210,620	$ 3,128	$ (12,884)	197,566	19,810	3,000
Balance, shares at Jun. 30, 2020		31,283	(1,966)
Balance at Mar. 31, 2020	219,495	$ 3,128	$ (12,974)	196,972	29,369	3,000
Balance, shares at Mar. 31, 2020		31,283	(1,980)
Net loss	(365)				(365)
Dividend accrued on redeemable preferred stock	(8,689)				(8,689)
Accretion of redeemable preferred stock	(505)				(505)
Stock-based compensation	684			684
Other			$ 90	(90)
Other, Shares			14
Balance at Jun. 30, 2020	$ 210,620	$ 3,128	$ (12,884)	$ 197,566	$ 19,810	$ 3,000
Balance, shares at Jun. 30, 2020		31,283	(1,966)