SEGMENT INFORMATION - Financial Data (Details) $ in Thousands	3 Months Ended
	Apr. 01, 2023 USD ($) segment	Apr. 02, 2022 USD ($)	Dec. 31, 2022 USD ($)
Segment Reporting Information [Line Items]
Number of operating segments | segment	3
Number of reportable segments | segment	3
Total revenue	$ 435,388	$ 420,947
(Loss) income from operation before taxes	(37,678)	(39,543)
Interest expense	27,420	20,149
Depreciation, depletion and amortization	50,188	50,479
Accretion	706	714
Loss on debt financings	493	0
Gain on sale of businesses	0	(14,205)
Non-cash compensation	4,708	5,422
Other	(4,636)	247
Total Adjusted EBITDA	41,201	23,263
Total purchases of property, plant and equipment	63,584	57,774
Total depreciation, depletion, amortization and accretion	50,894	51,193
Total assets	4,214,940		$ 4,255,692
Operating segment
Segment Reporting Information [Line Items]
Total purchases of property, plant and equipment	60,688	57,315
Total depreciation, depletion, amortization and accretion	49,906	50,444
Total assets	3,673,584		3,590,603
Corporate, non-segment
Segment Reporting Information [Line Items]
Total Adjusted EBITDA	(10,339)	(11,746)
Total purchases of property, plant and equipment	2,896	459
Total depreciation, depletion, amortization and accretion	988	749
Total assets	541,356		665,089
West
Segment Reporting Information [Line Items]
Total revenue	250,882	252,232
West | Operating segment
Segment Reporting Information [Line Items]
Total Adjusted EBITDA	32,678	32,692
Total purchases of property, plant and equipment	38,174	26,874
Total depreciation, depletion, amortization and accretion	26,373	24,575
Total assets	1,632,437		1,565,776
East
Segment Reporting Information [Line Items]
Total revenue	130,389	122,490
East | Operating segment
Segment Reporting Information [Line Items]
Total Adjusted EBITDA	18,852	8,136
Total purchases of property, plant and equipment	15,518	24,326
Total depreciation, depletion, amortization and accretion	15,535	18,295
Total assets	1,155,539		1,151,223
Cement
Segment Reporting Information [Line Items]
Total revenue	54,117	46,225
Cement | Operating segment
Segment Reporting Information [Line Items]
Total Adjusted EBITDA	10	(5,819)
Total purchases of property, plant and equipment	6,996	6,115
Total depreciation, depletion, amortization and accretion	7,998	7,574
Total assets	$ 885,608		873,604
Summit Materials, LLC
Segment Reporting Information [Line Items]
Number of operating segments | segment	3
Number of reportable segments | segment	3
Total revenue	$ 435,388	420,947
(Loss) income from operation before taxes	(37,678)	(39,543)
Interest expense	27,420	20,149
Depreciation, depletion and amortization	50,188	50,479
Accretion	706	714
Loss on debt financings	493	0
Gain on sale of businesses	0	(14,205)
Non-cash compensation	4,708	5,422
Other	(4,636)	247
Total Adjusted EBITDA	41,201	23,263
Total purchases of property, plant and equipment	63,584	57,774
Total depreciation, depletion, amortization and accretion	50,894	51,193
Total assets	4,071,473		4,119,706
Summit Materials, LLC | Operating segment
Segment Reporting Information [Line Items]
Total purchases of property, plant and equipment	60,688	57,315
Total depreciation, depletion, amortization and accretion	49,906	50,444
Total assets	3,673,584		3,590,603
Summit Materials, LLC | Corporate, non-segment
Segment Reporting Information [Line Items]
Total Adjusted EBITDA	(10,339)	(11,746)
Total purchases of property, plant and equipment	2,896	459
Total depreciation, depletion, amortization and accretion	988	749
Total assets	397,889		529,103
Summit Materials, LLC | West
Segment Reporting Information [Line Items]
Total revenue	250,882	252,232
Summit Materials, LLC | West | Operating segment
Segment Reporting Information [Line Items]
Total Adjusted EBITDA	32,678	32,692
Total purchases of property, plant and equipment	38,174	26,874
Total depreciation, depletion, amortization and accretion	26,373	24,575
Total assets	1,632,437		1,565,776
Summit Materials, LLC | East
Segment Reporting Information [Line Items]
Total revenue	130,389	122,490
Summit Materials, LLC | East | Operating segment
Segment Reporting Information [Line Items]
Total Adjusted EBITDA	18,852	8,136
Total purchases of property, plant and equipment	15,518	24,326
Total depreciation, depletion, amortization and accretion	15,535	18,295
Total assets	1,155,539		1,151,223
Summit Materials, LLC | Cement
Segment Reporting Information [Line Items]
Total revenue	54,117	46,225
Summit Materials, LLC | Cement | Operating segment
Segment Reporting Information [Line Items]
Total Adjusted EBITDA	10	(5,819)
Total purchases of property, plant and equipment	6,996	6,115
Total depreciation, depletion, amortization and accretion	7,998	$ 7,574
Total assets	$ 885,608		$ 873,604