REVENUE RECOGNITION - By Product (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 30, 2024	Apr. 01, 2023
Revenue from External Customer [Line Items]
Total revenue	$ 805,015	$ 435,388
Aggregates
Revenue from External Customer [Line Items]
Total revenue	145,511	143,653
Cement
Revenue from External Customer [Line Items]
Total revenue	224,097	49,013
Ready-mix concrete
Revenue from External Customer [Line Items]
Total revenue	312,047	138,778
Asphalt
Revenue from External Customer [Line Items]
Total revenue	27,985	26,635
Paving and related services
Revenue from External Customer [Line Items]
Total revenue	40,922	27,184
Other
Revenue from External Customer [Line Items]
Total revenue	54,453	50,125
Summit Materials, LLC
Revenue from External Customer [Line Items]
Total revenue	805,015	435,388
Summit Materials, LLC | Aggregates
Revenue from External Customer [Line Items]
Total revenue	145,511	143,653
Summit Materials, LLC | Cement
Revenue from External Customer [Line Items]
Total revenue	224,097	49,013
Summit Materials, LLC | Ready-mix concrete
Revenue from External Customer [Line Items]
Total revenue	312,047	138,778
Summit Materials, LLC | Asphalt
Revenue from External Customer [Line Items]
Total revenue	27,985	26,635
Summit Materials, LLC | Paving and related services
Revenue from External Customer [Line Items]
Total revenue	40,922	27,184
Summit Materials, LLC | Other
Revenue from External Customer [Line Items]
Total revenue	$ 54,453	$ 50,125