REVENUE RECOGNITION - By Product (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Oct. 01, 2022	Oct. 02, 2021	Oct. 01, 2022	Oct. 02, 2021
Revenue from External Customer [Line Items]
Total revenue	$ 752,747	$ 717,240	$ 1,860,248	$ 1,813,001
Aggregates
Revenue from External Customer [Line Items]
Total revenue	163,524	160,317	448,397	431,201
Cement
Revenue from External Customer [Line Items]
Total revenue	112,489	87,645	241,858	207,953
Ready-mix concrete
Revenue from External Customer [Line Items]
Total revenue	189,081	183,114	530,001	525,208
Asphalt
Revenue from External Customer [Line Items]
Total revenue	106,804	116,364	218,083	238,674
Paving and related services
Revenue from External Customer [Line Items]
Total revenue	120,327	112,671	249,547	257,966
Other
Revenue from External Customer [Line Items]
Total revenue	60,522	57,129	172,362	151,999
Summit Materials, LLC
Revenue from External Customer [Line Items]
Total revenue	752,747	717,240	1,860,248	1,813,001
Summit Materials, LLC | Aggregates
Revenue from External Customer [Line Items]
Total revenue	163,524	160,317	448,397	431,201
Summit Materials, LLC | Cement
Revenue from External Customer [Line Items]
Total revenue	112,489	87,645	241,858	207,953
Summit Materials, LLC | Ready-mix concrete
Revenue from External Customer [Line Items]
Total revenue	189,081	183,114	530,001	525,208
Summit Materials, LLC | Asphalt
Revenue from External Customer [Line Items]
Total revenue	106,804	116,364	218,083	238,674
Summit Materials, LLC | Paving and related services
Revenue from External Customer [Line Items]
Total revenue	120,327	112,671	249,547	257,966
Summit Materials, LLC | Other
Revenue from External Customer [Line Items]
Total revenue	$ 60,522	$ 57,129	$ 172,362	$ 151,999