ACQUISITIONS, DISPOSTIONS, GOODWILL AND INTANGIBLES - Summary of Goodwill by Reportable Segments (Details) $ in Thousands	3 Months Ended
Mar. 30, 2024 USD ($)
Goodwill [Roll Forward]
Balance—December 30, 2023	$ 1,224,861
Acquisitions	805,047
Dispositions	(37,938)
Foreign currency translation adjustments	(1,488)
Balance—March 30, 2024	1,990,482
West
Goodwill [Roll Forward]
Balance—December 30, 2023	658,704
Acquisitions	36,101
Dispositions	0
Foreign currency translation adjustments	(1,488)
Balance—March 30, 2024	693,317
East
Goodwill [Roll Forward]
Balance—December 30, 2023	361,501
Acquisitions	0
Dispositions	(37,938)
Foreign currency translation adjustments	0
Balance—March 30, 2024	323,563
Cement
Goodwill [Roll Forward]
Balance—December 30, 2023	204,656
Acquisitions	768,946
Dispositions	0
Foreign currency translation adjustments	0
Balance—March 30, 2024	973,602
Summit Materials, LLC
Goodwill [Roll Forward]
Balance—December 30, 2023	1,225,861
Acquisitions	805,047
Dispositions	(37,938)
Foreign currency translation adjustments	(1,488)
Balance—March 30, 2024	1,991,482
Summit Materials, LLC \| West
Goodwill [Roll Forward]
Balance—December 30, 2023	659,704
Acquisitions	36,101
Dispositions	0
Foreign currency translation adjustments	(1,488)
Balance—March 30, 2024	694,317
Summit Materials, LLC \| East
Goodwill [Roll Forward]
Balance—December 30, 2023	361,501
Acquisitions	0
Dispositions	(37,938)
Foreign currency translation adjustments	0
Balance—March 30, 2024	323,563
Summit Materials, LLC \| Cement
Goodwill [Roll Forward]
Balance—December 30, 2023	204,656
Acquisitions	768,946
Dispositions	0
Foreign currency translation adjustments	0
Balance—March 30, 2024	$ 973,602

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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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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 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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