GOODWILL AND INTANGIBLE ASSETS - Rollforward of Company's Goodwill (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 25, 2021	Dec. 26, 2020	Dec. 28, 2019
Goodwill [Roll Forward]
Gross carrying amount, beginning balance	$ 2,814,168	$ 2,545,565
Adjustments to goodwill, acquisitions	974,919	229,025
Adjustments to goodwill, foreign exchange	(40,313)	39,578
Adjustments to goodwill, divestitures	(31,893)
Gross carrying amount, ending balance	3,716,881	2,814,168
Accumulated impairment loss - DSA	(1,005,000)	(1,005,000)	$ (1,005,000)
Goodwill	2,711,881	1,809,168	$ 1,540,565
RMS
Goodwill [Roll Forward]
Gross carrying amount, beginning balance	287,759	56,586
Adjustments to goodwill, acquisitions	0	229,654
Adjustments to goodwill, foreign exchange	(106)	1,519
Adjustments to goodwill, divestitures	(4,129)
Gross carrying amount, ending balance	283,524	287,759
DSA
Goodwill [Roll Forward]
Gross carrying amount, beginning balance	2,383,130	2,350,223
Adjustments to goodwill, acquisitions	123,091	(629)
Adjustments to goodwill, foreign exchange	(28,715)	33,536
Adjustments to goodwill, divestitures	0
Gross carrying amount, ending balance	2,477,506	2,383,130
Manufacturing
Goodwill [Roll Forward]
Gross carrying amount, beginning balance	143,279	138,756
Adjustments to goodwill, acquisitions	851,828	0
Adjustments to goodwill, foreign exchange	(11,492)	4,523
Adjustments to goodwill, divestitures	(27,764)
Gross carrying amount, ending balance	$ 955,851	$ 143,279

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.

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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 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.

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Amount of divestiture 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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