Condensed Consolidated Statements of Stockholders' Equity (Unaudited) - USD ($) $ in Thousands	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Total
Balance (in shares) at Dec. 31, 2018	166,713,784
Balance at Dec. 31, 2018	$ 1,667	$ 417,844	$ (253,001)	$ 166,510
Net income (loss)			(25,455)	(25,455)
Stock-based compensation		373		373
Stock options exercised (in shares)	422,614
Stock options exercised	$ 4	397		401
Balance (in shares) at Mar. 31, 2019	167,136,398
Balance at Mar. 31, 2019	$ 1,671	418,614	(278,456)	$ 141,829
Balance (in shares) at Dec. 31, 2019	168,361,061			168,361,061
Balance at Dec. 31, 2019	$ 1,684	420,140	(318,005)	$ 103,819
Net income (loss)			41,443	41,443
Stock-based compensation		230		230
Restricted stock cancellations and forfeitures (in shares)	(291,756)
Restricted stock cancellations and forfeitures	$ (3)	3
Balance (in shares) at Mar. 31, 2020	168,069,305			168,069,305
Balance at Mar. 31, 2020	$ 1,681	$ 420,373	$ (276,562)	$ 145,492