Goodwill and Intangible Assets - Gross Carrying Amount and Accumulated Amortization of Goodwill (Details) $ in Thousands	9 Months Ended
Sep. 24, 2016 USD ($)
Changes in gross carrying amount and accumulated amortization of goodwill
Gross carrying amount, balance at the beginning of the period	$ 438,829
Adjustments to Goodwill, Acquisitions	340,832
Adjustments to Goodwill, Transfers	0
Adjustments to Goodwill, Foreign Exchange	(16,085)
Gross carrying amount, balance at the end of the period	763,576
RMS
Changes in gross carrying amount and accumulated amortization of goodwill
Gross carrying amount, balance at the beginning of the period	58,167
Adjustments to Goodwill, Acquisitions	0
Adjustments to Goodwill, Transfers	(342)
Adjustments to Goodwill, Foreign Exchange	(479)
Gross carrying amount, balance at the end of the period	57,346
DSA
Changes in gross carrying amount and accumulated amortization of goodwill
Gross carrying amount, balance at the beginning of the period	247,050
Adjustments to Goodwill, Acquisitions	293,973
Adjustments to Goodwill, Transfers	0
Adjustments to Goodwill, Foreign Exchange	(7,914)
Gross carrying amount, balance at the end of the period	533,109
Manufacturing
Changes in gross carrying amount and accumulated amortization of goodwill
Gross carrying amount, balance at the beginning of the period	133,612
Adjustments to Goodwill, Acquisitions	46,859
Adjustments to Goodwill, Transfers	342
Adjustments to Goodwill, Foreign Exchange	(7,692)
Gross carrying amount, balance at the end of the period	$ 173,121

Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits 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
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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Amount before 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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a,h)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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- Definition

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=73531572&loc=d3e961-128460

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

Amount of transfers into (out 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 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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