CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE INCOME (Unaudited) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
Mar. 30, 2014	Mar. 31, 2013
Income Statement [Abstract]
Revenues	$ 487,690	$ 507,473
Cost of sales	(311,973)	(340,120)
Gross profit	175,717	167,353
Selling, general and administrative expenses	(94,848)	(91,982)
Research and development	(20,571)	(20,425)
Amortization of intangibles	(11,741)	(12,977)
Income from equity method investment	954	2,271
Operating income	49,511	44,240
Interest expense	(18,820)	(15,905)
Interest income	150	108
Income from continuing operations before taxes	30,841	28,443
Income tax expense	(5,685)	(6,198)
Income from continuing operations	25,156	22,245
Loss from disposal of discontinued operations, net of tax	(562)
Net income	24,594	22,245
Weighted average number of common shares and equivalents:
Basic	43,514	44,420
Diluted	44,293	45,427
Basic income (loss) per share
Continuing operations	$ 0.58	$ 0.50
Discontinued operations	$ (0.01)
Net income	$ 0.57	$ 0.50
Diluted income (loss) per share
Continuing operations	$ 0.57	$ 0.49
Discontinued operations	$ (0.01)
Net income	$ 0.56	$ 0.49
Comprehensive income	$ 13,281	$ 14,892
Dividends declared per share	$ 0.05	$ 0.05

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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Balance Type:	debit
Period Type:	duration