Consolidated Statement of Shareholders' Equity Statement - USD ($) $ in Thousands	Total	Common Stock [Member]	Paid-in Capital [Member]	Accumulated Deficit [Member]	Accumulated Other Comprehensive Income [Member]
Balances at Dec. 31, 2014	$ 590,630	$ 450	$ 806,810	$ (226,850)	$ 10,220
Net income (loss)	(33,400)			(33,400)
Other comprehensive income (loss)	(13,210)				(13,210)
Shares surrendered upon option and restricted stock vesting to cover tax	(2,770)		(2,770)
Stock option exercises and restricted stock vesting	500	0	500
Tax effect from stock based compensation	590		590
Non-cash compensation expense	7,030		7,030
Distribution of the Cequent business	(2,180)			6,130	(8,310)
Balances at Dec. 31, 2015	547,190	450	812,160	(254,120)	(11,300)
Net income (loss)	(39,800)			(39,800)
Other comprehensive income (loss)	(13,100)				(13,100)
Shares surrendered upon option and restricted stock vesting to cover tax	(1,590)		(1,590)
Stock option exercises and restricted stock vesting	160	10	150
Tax effect from stock based compensation	(80)		(80)
Non-cash compensation expense	6,940		6,940
Balances at Dec. 31, 2016	499,720	460	817,580	(293,920)	(24,400)
Net income (loss)	30,960			30,960
Other comprehensive income (loss)	7,070				7,070
Shares surrendered upon option and restricted stock vesting to cover tax	(510)		(510)
Non-cash compensation expense	6,780		6,780
Balances at Dec. 31, 2017	$ 544,020	$ 460	$ 823,850	$ (262,960)	$ (17,330)