ACQUISITIONS, DISPOSTIONS, GOODWILL AND INTANGIBLES - Narrative (Details) $ in Thousands	3 Months Ended
Apr. 02, 2022 USD ($) business	Apr. 03, 2021 USD ($)
Business Acquisition [Line Items]
Proceeds from sale of businesses	$ 47,821	$ 33,077
Gain on sale of business	$ 14,205	15,668
East
Business Acquisition [Line Items]
Number of businesses sold \| business	1
Summit Materials, LLC
Business Acquisition [Line Items]
Proceeds from sale of businesses	$ 47,821	33,077
Gain on sale of business	$ 14,205	$ 15,668
Summit Materials, LLC \| East
Business Acquisition [Line Items]
Number of businesses sold \| business	1

Number Of Businesses Sold

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+ References

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Amount of gain (loss) from sale and disposal of integrated set of activities and assets capable of being conducted and managed for purpose of providing return in form of dividend, lower cost, or other economic benefit to investor, owner, member and participant.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3602-108585

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 1B
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109239629&loc=SL4582445-111684

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The cash inflow associated with the amount received from the sale of a portion of the company's business, for example a segment, division, branch or other business, during the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3179-108585

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