COMMITMENTS AND CONTINGENCIES - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
Apr. 02, 2022	Jan. 01, 2022
Loss Contingencies [Line Items]
Anticipated costs	$ 107.6	$ 112.4
Term of purchase commitments	1 year
Site Restoration Obligations \| Other noncurrent liabilities
Loss Contingencies [Line Items]
Site restoration obligation, non-current	$ 37.0	37.7
Site Restoration Obligations \| Accrued expenses.
Loss Contingencies [Line Items]
Site restoration obligation, current	$ 4.3	7.4
Summit Materials, LLC
Loss Contingencies [Line Items]
Term of purchase commitments	1 year
Summit Materials, LLC \| Site Restoration Obligations
Loss Contingencies [Line Items]
Anticipated costs	$ 107.6	112.4
Summit Materials, LLC \| Site Restoration Obligations \| Other noncurrent liabilities
Loss Contingencies [Line Items]
Site restoration obligation, non-current	37.0	37.7
Summit Materials, LLC \| Site Restoration Obligations \| Accrued expenses.
Loss Contingencies [Line Items]
Site restoration obligation, current	$ 4.3	$ 7.4

Total undiscounted anticipated costs for asset retirement obligations.

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- Definition

Term of purchase commitment, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

Current portion of the carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849

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- Definition

Noncurrent portion of the carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees.

+ References

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- Definition

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+ References

No definition available.

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