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ACQUISITIONS, DISPOSTIONS, GOODWILL AND INTANGIBLES - Pro forma Preliminary Price Allocation (Details) - USD ($) $ in Thousands		3 Months Ended
	Jan. 12, 2024	Mar. 30, 2024	Apr. 01, 2023
Business Acquisition [Line Items]
Cash consideration		$ 1,100,919	$ 55,477
Summit Materials, LLC
Business Acquisition [Line Items]
Cash consideration		$ 1,100,919	$ 55,477
Argos USA
Business Acquisition [Line Items]
Cash consideration	$ 1,145,463
Fair value of stock consideration issued	1,973,750
Total fair value of consideration transferred	3,119,213
Argos USA \| Summit Materials, LLC
Business Acquisition [Line Items]
Cash consideration	1,145,463
Fair value of stock consideration issued	1,973,750
Total fair value of consideration transferred	$ 3,119,213