GOODWILL AND INTANGIBLE ASSETS - Rollforward of Goodwill (Details) $ in Thousands	3 Months Ended
Mar. 28, 2020 USD ($)
Goodwill [Roll Forward]
Beginning balance	$ 1,540,565
Acquisitions	208,554
Foreign exchange	(17,282)
Ending balance	1,731,837
RMS
Goodwill [Roll Forward]
Beginning balance	56,586
Acquisitions	209,104
Foreign exchange	(219)
Ending balance	265,471
DSA
Goodwill [Roll Forward]
Beginning balance	1,345,223
Acquisitions	(550)
Foreign exchange	(13,865)
Ending balance	1,330,808
Manufacturing
Goodwill [Roll Forward]
Beginning balance	138,756
Acquisitions	0
Foreign exchange	(3,198)
Ending balance	$ 135,558

Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=108376223&loc=d3e13816-109267

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- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=108376223&loc=d3e13816-109267

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- Definition

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/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=108376223&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (h)
-URI http://asc.fasb.org/extlink&oid=108376223&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

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