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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Goodwill and Other Intangible Assets - Amortization of Intangibles (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 29, 2015	Mar. 30, 2014	Dec. 31, 2014
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Amortization Expense, Remainder of Fiscal Year	$ 7,378
Finite-Lived Intangible Assets [Abstract]
Finite-Lived Intangible Assets, Amortization Expense	2,563us-gaap_AmortizationOfIntangibleAssets	2,554us-gaap_AmortizationOfIntangibleAssets
Finite-Lived Intangible Assets, Future Amortization Expense [Abstract]
Expected amortization, 2016	9,141
Expected amortization, 2017	8,128
Expected amortization, 2018	6,879
Expected amortization, 2019	5,486
Thereafter	13,216
Total intangible assets included in other long-term assets	50,228us-gaap_FiniteLivedIntangibleAssetsNet		54,111us-gaap_FiniteLivedIntangibleAssetsNet
Patents, trademarks and other [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Amortization Expense, Remainder of Fiscal Year	2,632
Finite-Lived Intangible Assets [Abstract]
Finite-Lived Intangible Assets, Amortization Expense	1,071	1,001
Finite-Lived Intangible Assets, Future Amortization Expense [Abstract]
Expected amortization, 2016	2,812
Expected amortization, 2017	2,367
Expected amortization, 2018	1,584
Expected amortization, 2019	1,296
Thereafter	800
Total intangible assets included in other long-term assets	11,491		12,528
Customer relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Amortization Expense, Remainder of Fiscal Year	2,054
Finite-Lived Intangible Assets [Abstract]
Finite-Lived Intangible Assets, Amortization Expense	639	666
Finite-Lived Intangible Assets, Future Amortization Expense [Abstract]
Expected amortization, 2016	2,740
Expected amortization, 2017	2,393
Expected amortization, 2018	2,355
Expected amortization, 2019	1,868
Thereafter	4,060
Total intangible assets included in other long-term assets	15,470		15,876
Developed technology [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Amortization Expense, Remainder of Fiscal Year	2,692
Finite-Lived Intangible Assets [Abstract]
Finite-Lived Intangible Assets, Amortization Expense	853	887
Finite-Lived Intangible Assets, Future Amortization Expense [Abstract]
Expected amortization, 2016	3,589
Expected amortization, 2017	3,368
Expected amortization, 2018	2,940
Expected amortization, 2019	2,322
Thereafter	8,356
Total intangible assets included in other long-term assets	$ 23,267		$ 25,707
Maximum [Member] \| Patents, trademarks and other [Member]
Finite-Lived Intangible Assets [Abstract]
Finite-lived intangible assets, useful life	10 years
Maximum [Member] \| Customer relationships [Member]
Finite-Lived Intangible Assets [Abstract]
Finite-lived intangible assets, useful life	10 years
Maximum [Member] \| Developed technology [Member]
Finite-Lived Intangible Assets [Abstract]
Finite-lived intangible assets, useful life	10 years
Minimum [Member] \| Patents, trademarks and other [Member]
Finite-Lived Intangible Assets [Abstract]
Finite-lived intangible assets, useful life	2 years
Minimum [Member] \| Customer relationships [Member]
Finite-Lived Intangible Assets [Abstract]
Finite-lived intangible assets, useful life	5 years
Minimum [Member] \| Developed technology [Member]
Finite-Lived Intangible Assets [Abstract]
Finite-lived intangible assets, useful life	5 years 6 months