Unaudited Condensed Consolidated Statement of Changes in Stockholders' Equity (Deficit) - 9 months ended Sep. 30, 2017 - USD ($) $ in Thousands	Total	Common Stock	Additional paid-in capital	Retained earnings	Accumulated other comprehensive (loss) income	Treasury Stock
Balance at December 31, 2016 (shares) at Dec. 31, 2016	196,524,010	196,524,010
Balance at December 31, 2016 at Dec. 31, 2016	$ (146,338)	$ (1,965)	$ (71,420)	$ (72,692)	$ (261)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Other comprehensive income (loss)	$ (495)				(495)
Issuance of restricted stock (shares)	35,430
Issuance of restricted stock awards	$ 815	$ 0	815
Exercise of stock options (shares)	785,257	785,257
Exercise of stock options	$ 4,527	$ 8	4,519
Repurchases of common stock (shares)						2,092,774
Repurchases of common stock	(50,000)					$ 50,000
Stock-based compensation expense	2,161		2,161
Net income	$ 139,909			139,909
Balance at September 30, 2017 (shares) at Sep. 30, 2017	195,251,923	197,344,697				2,092,774
Balance at September 30, 2017 at Sep. 30, 2017	$ (243,255)	$ 1,973	$ 78,915	$ 212,601	$ (234)	$ (50,000)