Condensed Consolidated Stockholders' Equity Statement (Unaudited) - 6 months ended Jul. 03, 2016 - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock [Member]	Additional Paid-In Capital [Member]	Retained Earnings [Member]	Treasury Stock [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Noncontrolling Interest [Member]
Beginning balance at Dec. 31, 2015	$ 825,523	$ 503	$ 605,660	$ 679,716	$ (402,793)	$ (58,987)	$ 1,424
Beginning balance, Treasury shares at Dec. 31, 2015					(8,354)
Beginning balance, shares at Dec. 31, 2015		50,335
Net income (loss)	58,175			58,373			(198)
Foreign currency translation	(1,093)					(1,064)	(29)
Adjustments to pension and postretirement liability, net of $0.6 million tax	982					982
Other comprehensive income (loss), net of tax	(111)					(82)
Exercise of stock options, net of tax withholding forfeitures	(827)		(963)		$ 136
Exercise of stock options, net of tax withholding forfeitures, shares					19
Conversion of restricted stock units into common stock, net of tax withholding forfeitures	(2,771)		(4,339)		$ 1,568
Conversion of restricted stock units into common stock, net of tax withholding forfeitures, shares					111
Share-based compensation	8,703		8,703
Dividends ($0.10 per share)	(4,237)			(4,237)
Ending balance at Jul. 03, 2016	$ 884,455	$ 503	$ 609,061	$ 733,852	$ (401,089)	$ (59,069)	$ 1,197
Ending balance, Treasury shares at Jul. 03, 2016					(8,224)
Ending balance, shares at Jul. 03, 2016		50,335