CONSOLIDATED STATEMENT OF CHANGES IN EQUITY - USD ($) shares in Thousands, $ in Thousands	Total	Accumulated Deficit	AOCI Attributable to Parent	Common Stock	Additional Paid-in Capital	Treasury Stock
Balance at Dec. 31, 2017	$ 81,796	$ (715,476)	$ (113)	$ 2,157	$ 812,536	$ (17,308)
Balance (in shares) at Dec. 31, 2017				21,573
Balance (in shares) at Dec. 31, 2017						999
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	(6,170)	(6,170)
Cancellations of and restricted stock withheld for taxes	(150)				(17)	$ (133)
Issuance of restricted stock, net of tax withholdings (in shares)						13
Stock-based compensation expense	277				277
Other comprehensive loss	82		82
Balance at Mar. 31, 2018	75,835	(721,646)	(31)	$ 2,157	812,796	$ (17,441)
Balance (in shares) at Mar. 31, 2018				21,573
Balance (in shares) at Mar. 31, 2018						1,012
Balance at Dec. 31, 2018	66,979	(731,105)	0	$ 2,157	810,928	$ (15,001)
Balance (in shares) at Dec. 31, 2018				21,573
Balance (in shares) at Dec. 31, 2018						914
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	21,663	21,663
Stock options exercised, net of tax withholdings	0				0	$ 0
Stock options exercised, net of tax withholdings (in shares)						1
Cancellations of and restricted stock withheld for taxes	(149)				7	$ (156)
Issuance of restricted stock, net of tax withholdings (in shares)						83
Stock-based compensation expense	417				417
Other comprehensive loss	(31)		(31)
Balance at Mar. 31, 2019	$ 88,879	$ (709,442)	$ (31)	$ 2,157	$ 811,352	$ (15,157)
Balance (in shares) at Mar. 31, 2019				21,573
Balance (in shares) at Mar. 31, 2019						998