DEBT - Summary of Activity for Deferred Financing Fees (Details) - USD ($) $ in Thousands	3 Months Ended
	Apr. 02, 2022	Apr. 03, 2021
Deferred Finance Costs, Own-share Lending Arrangement, Issuance Costs, Accumulated Amortization [Roll Forward]
Beginning balance	$ 13,049	$ 18,367
Amortization	(692)	(836)
Ending balance	12,357	17,531
Summit Materials, LLC
Deferred Finance Costs, Own-share Lending Arrangement, Issuance Costs, Accumulated Amortization [Roll Forward]
Beginning balance	13,049	18,367
Amortization	(692)	(836)
Ending balance	$ 12,357	$ 17,531