Condensed Consolidated Statement of Stockholders' Equity Statement - 9 months ended Sep. 30, 2018 - USD ($) $ in Thousands	Total	Common Stock	Treasury Stock	Additional Paid-in-Capital	Accumulated Other Comprehensive Loss	Retained Earnings
Beginning Balance (in shares) at Dec. 31, 2017		64,075,000	10,020,000
Total stockholders' equity - Beginning Balance at Dec. 31, 2017	$ 284,545	$ 6	$ (55,873)	$ 235,199	$ (19,229)	$ 124,442
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(46,921)					(46,921)
Net current-period other comprehensive (loss) income	(3,951)				(3,951)
Total other comprehensive loss, net of tax	(3,951)
Comprehensive loss	(50,872)
Issuance of common stock upon exercise of stock awards (in shares)		359,000
Issuance of common stock upon exercise of stock awards	$ (438)	$ 0		(438)
Stock Repurchased During Period, Shares	2,667,732		2,668,000
Stock Repurchased During Period, Value	$ (25,598)		$ (25,598)
Stock-based compensation expense	3,624			3,624
Cumulative effect of change related to adoption of ASC and ASU (Accounting Standards Update 2014-09) at Dec. 31, 2017	482					482
Cumulative effect of change related to adoption of ASC and ASU (Accounting Standards Update 2016-16) at Dec. 31, 2017	153					153
Ending Balance (in shares) at Sep. 30, 2018		64,434,000	12,688,000
Total stockholders' equity - Ending Balance at Sep. 30, 2018	$ 211,896	$ 6	$ (81,471)	$ 238,385	$ (23,180)	$ 78,156