GOODWILL AND INTANGIBLE ASSETS - Schedule of Goodwill by Segment (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 27, 2020	Dec. 29, 2019
Goodwill [Roll Forward]
Goodwill, beginning of period	$ 973,750	$ 949,750
Additions	2,197	0
Currency Translation	29,298	24,000
Goodwill, end of period	1,005,245	973,750
U.S.
Goodwill [Roll Forward]
Goodwill, beginning of period	41,936	41,936
Additions	0	0
Currency Translation	0	0
Goodwill, end of period	41,936	41,936
U.K. and Europe
Goodwill [Roll Forward]
Goodwill, beginning of period	806,207	782,207
Additions	0	0
Currency Translation	29,298	24,000
Goodwill, end of period	835,505	806,207
Mexico
Goodwill [Roll Forward]
Goodwill, beginning of period	125,607	125,607
Additions	2,197	0
Currency Translation	0	0
Goodwill, end of period	$ 127,804	$ 125,607

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/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(10)(1))
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=120320667&loc=SL49117168-202975

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=99380562&loc=d3e13770-109266

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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-Paragraph 1
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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.

+ References

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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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