CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) $ in Thousands	Preferred Stock [Member]	Common Stock [Member]	Additional Paid-In Capital [Member]	Accumulated Other Comprehensive Loss [Member]	Retained Earnings [Member]	Total
Balances at Dec. 31, 2018	$ 103,865	$ 2	$ 132,666	$ (6,513)	$ 471,112	$ 701,132
Balances, Shares at Dec. 31, 2018	4,155,000	18,764,000
Net income (loss)					18,574	18,574
Preferred stock dividends, $0.53125/share					(2,207)	(2,207)
Foreign currency translation adjustment				(81)		(81)
Repurchase of common stock			(13,946)			(13,946)
Repurchase of common stock, Shares		(595,000)
Exercise of stock options			107			107
Exercise of stock options, Shares		27,000
Stock-based compensation, net of taxes			730			730
Stock-based compensation, net of taxes, Shares		12,000
Balances at Mar. 31, 2019	$ 103,865	$ 2	119,557	(6,594)	487,479	704,309
Balances, Shares at Mar. 31, 2019	4,155,000	18,208,000
Balances at Dec. 31, 2018	$ 103,865	$ 2	132,666	(6,513)	471,112	701,132
Balances, Shares at Dec. 31, 2018	4,155,000	18,764,000
Net income (loss)						24,068
Preferred stock dividends, $0.53125/share						(4,414)
Foreign currency translation adjustment						(76)
Balances at Jun. 30, 2019	$ 103,865	$ 2	100,301	(6,589)	490,766	688,345
Balances, Shares at Jun. 30, 2019	4,155,000	17,420,000
Balances at Mar. 31, 2019	$ 103,865	$ 2	119,557	(6,594)	487,479	704,309
Balances, Shares at Mar. 31, 2019	4,155,000	18,208,000
Net income (loss)					5,494	5,494
Preferred stock dividends, $0.53125/share					(2,207)	(2,207)
Foreign currency translation adjustment				5		5
Repurchase of common stock			(20,172)			(20,172)
Repurchase of common stock, Shares		(863,000)
Exercise of stock options			228			228
Exercise of stock options, Shares		35,000
Stock-based compensation, net of taxes			688			688
Stock-based compensation, net of taxes, Shares		40,000
Balances at Jun. 30, 2019	$ 103,865	$ 2	100,301	(6,589)	490,766	688,345
Balances, Shares at Jun. 30, 2019	4,155,000	17,420,000
Balances at Dec. 31, 2019	$ 103,865	$ 2	102,709	(6,630)	493,294	693,240
Balances, Shares at Dec. 31, 2019	4,155,000	17,479,000
Net income (loss)					(1,330)	(1,330)
Preferred stock dividends, $0.53125/share					(2,207)	(2,207)
Foreign currency translation adjustment				(137)		(137)
Exercise of stock options			113			113
Exercise of stock options, Shares		8,000
Stock-based compensation, net of taxes			468			468
Stock-based compensation, net of taxes, Shares		19,000
Balances at Mar. 31, 2020	$ 103,865	$ 2	103,290	(6,767)	489,757	690,147
Balances, Shares at Mar. 31, 2020	4,155,000	17,506,000
Balances at Dec. 31, 2019	$ 103,865	$ 2	102,709	(6,630)	493,294	693,240
Balances, Shares at Dec. 31, 2019	4,155,000	17,479,000
Net income (loss)						(1,956)
Preferred stock dividends, $0.53125/share						(4,414)
Foreign currency translation adjustment						$ (36)
Repurchase of common stock, Shares						0
Balances at Jun. 30, 2020	$ 103,865	$ 2	103,342	(6,666)	486,924	$ 687,467
Balances, Shares at Jun. 30, 2020	4,155,000	17,553,000
Balances at Mar. 31, 2020	$ 103,865	$ 2	103,290	(6,767)	489,757	690,147
Balances, Shares at Mar. 31, 2020	4,155,000	17,506,000
Net income (loss)					(626)	(626)
Preferred stock dividends, $0.53125/share					(2,207)	(2,207)
Foreign currency translation adjustment				101		101
Exercise of stock options, Shares		3,000
Stock-based compensation, net of taxes			52			52
Stock-based compensation, net of taxes, Shares		44,000
Balances at Jun. 30, 2020	$ 103,865	$ 2	$ 103,342	$ (6,666)	$ 486,924	$ 687,467
Balances, Shares at Jun. 30, 2020	4,155,000	17,553,000