Property, Plant and Equipment, net and Intangibles, net - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2022	Jan. 01, 2022	Jan. 02, 2021
Property, Plant and Equipment [Line Items]
Depreciation, depletion and amortization expense	$ 184,300	$ 195,100	$ 195,300
Property, plant, and equipment and finance lease right-of-use asset, before accumulated depreciation and amortization	3,081,259	3,109,421
Finance lease right-of-use asset accumulated amortization	1,267,557	1,266,513
Current finance lease liabilities	6,959	17,624
Long-term finance lease liabilities	7,167	14,982
2023	7,443
2024	2,829
2025	2,415
2026	990
2027	760
Summit Materials, LLC
Property, Plant and Equipment [Line Items]
Depreciation, depletion and amortization expense	184,300	195,100	$ 195,300
Property, plant, and equipment and finance lease right-of-use asset, before accumulated depreciation and amortization	3,081,259	3,109,421
Finance lease right-of-use asset accumulated amortization	1,267,557	1,266,513
Current finance lease liabilities	6,959	17,624
Long-term finance lease liabilities	7,167	14,982
2023	7,443
2024	2,829
2025	2,415
2026	990
2027	760
Equipment And Building
Property, Plant and Equipment [Line Items]
Property, plant, and equipment and finance lease right-of-use asset, before accumulated depreciation and amortization	32,100	69,000
Finance lease right-of-use asset accumulated amortization	15,000	31,400
Equipment And Building \| Summit Materials, LLC
Property, Plant and Equipment [Line Items]
Property, plant, and equipment and finance lease right-of-use asset, before accumulated depreciation and amortization	32,100	69,000
Finance lease right-of-use asset accumulated amortization	$ 15,000	$ 31,400
Equipment
Property, Plant and Equipment [Line Items]
Equipment lease term	5 years
Equipment \| Summit Materials, LLC
Property, Plant and Equipment [Line Items]
Equipment lease term	5 years
Building
Property, Plant and Equipment [Line Items]
Equipment lease term	30 years
Building \| Summit Materials, LLC
Property, Plant and Equipment [Line Items]
Equipment lease term	30 years

The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

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Term of lessee's finance lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount, before accumulated depreciation and amortization, of property, plant, and equipment and finance lease right-of-use asset.

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