Goodwill Goodwill (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 28, 2015	Mar. 29, 2014
Goodwill [Line Items]
Goodwill, beginning	$ 340,743us-gaap_Goodwill	$ 12,274us-gaap_Goodwill
Addition due to acquisition	7,186
Other, including foreign currency translation	(324)us-gaap_GoodwillTranslationAdjustments	(33)us-gaap_GoodwillTranslationAdjustments
Goodwill, ending	347,605us-gaap_Goodwill	12,241us-gaap_Goodwill
Goodwill, Period Increase (Decrease)	6,862us-gaap_GoodwillPeriodIncreaseDecrease
CMH
Goodwill [Line Items]
Goodwill, beginning	47,483	12,274
Addition due to acquisition	0
Other, including foreign currency translation	37	(33)
Goodwill, ending	47,520	12,241
EM
Goodwill [Line Items]
Goodwill, beginning	293,260	0
Addition due to acquisition	7,186
Other, including foreign currency translation	(361)	0
Goodwill, ending	$ 300,085	$ 0

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

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Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 25

-Paragraph 16

-URI http://asc.fasb.org/extlink&oid=34752592&loc=d3e961-128460

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