GOODWILL AND INTANGIBLE ASSETS - Rollforward of Company's Goodwill (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 30, 2017	Dec. 31, 2016	Dec. 26, 2015
Goodwill [Roll Forward]
Gross carrying amount, beginning balance	$ 1,792,517	$ 1,443,829
Gross carrying amount, ending balance	1,809,906	1,792,517
Accumulated impairment loss - DSA	(1,005,000)	(1,005,000)	$ (1,005,000)
Goodwill	804,906	787,517	$ 438,829
RMS
Goodwill [Roll Forward]
Gross carrying amount, beginning balance	56,397	58,167
Adjustments to Goodwill, Acquisitions	0	0
Adjustments to Goodwill, Transfers		(342)
Adjustments to Goodwill, Foreign Exchange	1,725	(1,428)
Gross carrying amount, ending balance	58,122	56,397
DSA
Goodwill [Roll Forward]
Gross carrying amount, beginning balance	1,568,476	1,252,050
Adjustments to Goodwill, Acquisitions	11,942	337,872
Adjustments to Goodwill, Transfers		0
Adjustments to Goodwill, Foreign Exchange	29,758	(21,446)
Gross carrying amount, ending balance	1,610,176	1,568,476
Manufacturing
Goodwill [Roll Forward]
Gross carrying amount, beginning balance	167,644	133,612
Adjustments to Goodwill, Acquisitions	(36,000)	46,859
Adjustments to Goodwill, Transfers		342
Adjustments to Goodwill, Foreign Exchange	9,964	(13,169)
Gross carrying amount, ending balance	$ 141,608	$ 167,644

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
-Subparagraph (a)
-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

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975

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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.

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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.

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

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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=84229725&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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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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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.

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