Consolidated Statements Of Stockholders' Equity - USD ($)	Total	Common Stock	Paid-in Capital	Retained Earnings	Treasury Stock	Accumulated Other Comprehensive (Loss) Income
Balance at Dec. 31, 2014	$ 335,888,000	$ 111,000	$ 48,115,000	$ 322,672,000	$ (23,118,000)	$ (11,892,000)
Increase (Decrease) in Stockholders' Equity
Net (loss) income	(44,445,000)			(44,445,000)
Other comprehensive (loss) income, net of tax:
Pension liability adjustment	1,020,000					1,020,000
Foreign currency translation adjustment	(6,947,000)					(6,947,000)
Unrealized derivative (loss) gain on cash flow hedges	(121,000)					(121,000)
Purchase of common shares for treasury	(1,587,000)				(1,587,000)
Issuance of common shares, net of shares withheld for taxes	(1,044,000)		(3,158,000)		2,114,000
Stock based compensation and related excess tax benefit/deficiency	1,724,000		1,724,000
Cash dividends on common stock paid to shareholders	(1,656,000)			(1,656,000)
Balance at Dec. 31, 2015	282,832,000	111,000	46,681,000	276,571,000	(22,591,000)	(17,940,000)
Increase (Decrease) in Stockholders' Equity
Net (loss) income	(141,660,000)			(141,660,000)
Other comprehensive (loss) income, net of tax:
Pension liability adjustment	(1,370,000)					(1,370,000)
Foreign currency translation adjustment	(5,896,000)					(5,896,000)
Unrealized derivative (loss) gain on cash flow hedges	(83,000)					(83,000)
Purchase of common shares for treasury	(67,000)				(67,000)
Issuance of common shares, net of shares withheld for taxes	(275,000)		(3,597,000)		3,322,000
Stock based compensation and related excess tax benefit/deficiency	1,014,000		1,014,000
Cash dividends on common stock paid to shareholders	(1,244,000)			(1,244,000)
Balance at Dec. 31, 2016	133,251,000	111,000	44,098,000	133,667,000	(19,336,000)	(25,289,000)
Increase (Decrease) in Stockholders' Equity
Net (loss) income	4,113,000			4,113,000
Other comprehensive (loss) income, net of tax:
Pension liability adjustment	1,072,000					1,072,000
Foreign currency translation adjustment	6,024,000					6,024,000
Unrealized derivative (loss) gain on cash flow hedges	426,000					426,000
Issuance of common shares, net of shares withheld for taxes	(103,000)		(777,000)		674,000
Stock based compensation and related excess tax benefit/deficiency	1,696,000		1,696,000
Cash dividends on common stock paid to shareholders	0
Balance at Dec. 31, 2017	$ 146,479,000	$ 111,000	$ 45,017,000	$ 137,780,000	$ (18,662,000)	$ (17,767,000)