GOODWILL AND INTANGIBLE ASSETS - Rollforward of Company's Goodwill (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2016	Dec. 26, 2015	Dec. 27, 2014
Goodwill [Roll Forward]
Gross carrying amount, beginning balance	$ 1,443,829	$ 1,326,077
Adjustments to Goodwill, Acquisitions
Adjustments to Goodwill, Foreign Exchange
Adjustments to Goodwill, Transfers
Gross carrying amount, ending balance	1,792,517	1,443,829
Goodwill	787,517	438,829	$ 321,077
RMS
Goodwill [Roll Forward]
Gross carrying amount, beginning balance	58,167	59,196
Adjustments to Goodwill, Acquisitions	0	0
Adjustments to Goodwill, Foreign Exchange	(1,428)	(1,029)
Adjustments to Goodwill, Transfers	(342)
Gross carrying amount, ending balance	56,397	58,167
DSA
Goodwill [Roll Forward]
Gross carrying amount, beginning balance	1,252,050	1,234,302
Adjustments to Goodwill, Acquisitions	337,872	22,146
Adjustments to Goodwill, Foreign Exchange	(21,446)	(4,398)
Adjustments to Goodwill, Transfers	0
Gross carrying amount, ending balance	1,568,476	1,252,050
Accumulated impairment loss - DSA	(1,005,000)	(1,005,000)	$ (1,005,000)
Manufacturing
Goodwill [Roll Forward]
Gross carrying amount, beginning balance	133,612	32,579
Adjustments to Goodwill, Acquisitions	46,859	105,567
Adjustments to Goodwill, Foreign Exchange	(13,169)	(4,534)
Adjustments to Goodwill, Transfers	342
Gross carrying amount, ending balance	$ 167,644	$ 133,612

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=64834752&loc=SL49117168-202975

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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.

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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.

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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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- 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.

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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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