Condensed Consolidated Statements of Operations and Comprehensive Income - Unaudited - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2017	Apr. 01, 2016
Income Statement [Abstract]
Sales	$ 345,413	$ 332,238
Cost of sales	254,187	240,770
Gross profit	91,226	91,468
Operating expenses:
Selling, general and administrative expenses	39,499	41,888
Research, development and engineering costs, net	13,411	17,306
Other operating expenses, net	11,771	21,140
Total operating expenses	64,681	80,334
Operating income	26,545	11,134
Interest expense, net	28,893	27,617
Other expense (income), net	1,847	(3,721)
Loss before provision (benefit) for income taxes	(4,195)	(12,762)
Provision (benefit) for income taxes	144	(102)
Net loss	$ (4,339)	$ (12,660)
Loss per share:
Basic	$ (0.14)	$ (0.41)
Diluted	$ (0.14)	$ (0.41)
Weighted average shares outstanding:
Basic	31,016	30,718
Diluted	31,016	30,718
Comprehensive Income
Net loss	$ (4,339)	$ (12,660)
Foreign currency translation gain	6,536	18,760
Net change in cash flow hedges, net of tax	1,750	367
Other comprehensive income	8,286	19,127
Comprehensive income	$ 3,947	$ 6,467