Property, Plant and Equipment, net and Intangibles, net - Intangible Assets (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2022	Jan. 01, 2022	Jan. 02, 2021
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 86,887	$ 84,665
Accumulated Amortization	(15,503)	(15,269)
Net Carrying Amount	71,384	69,396
Amortization expense	3,500	3,700	$ 2,700
Estimated amortization expense
2023	4,010
2024	3,985
2025	3,944
2026	3,895
2027	3,883
Thereafter	51,667
Total	71,384	69,396
Summit Materials, LLC
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	86,887	84,665
Accumulated Amortization	(15,503)	(15,269)
Net Carrying Amount	71,384	69,396
Amortization expense	3,500	3,700	$ 2,700
Estimated amortization expense
2023	4,010
2024	3,985
2025	3,944
2026	3,895
2027	3,883
Thereafter	51,667
Total	71,384	69,396
Operating permits
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	38,677	33,671
Accumulated Amortization	(4,109)	(2,467)
Net Carrying Amount	34,568	31,204
Operating permits \| Summit Materials, LLC
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	38,677	33,671
Accumulated Amortization	(4,109)	(2,467)
Net Carrying Amount	34,568	31,204
Mineral leases
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	18,091	19,927
Accumulated Amortization	(7,056)	(8,922)
Net Carrying Amount	11,035	11,005
Mineral leases \| Summit Materials, LLC
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	18,091	19,927
Accumulated Amortization	(7,056)	(8,922)
Net Carrying Amount	11,035	11,005
Reserve rights
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	25,242	25,586
Accumulated Amortization	(3,872)	(3,329)
Net Carrying Amount	21,370	22,257
Reserve rights \| Summit Materials, LLC
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	25,242	25,586
Accumulated Amortization	(3,872)	(3,329)
Net Carrying Amount	21,370	22,257
Other
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	4,877	5,481
Accumulated Amortization	(466)	(551)
Net Carrying Amount	4,411	4,930
Other \| Summit Materials, LLC
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	4,877	5,481
Accumulated Amortization	(466)	(551)
Net Carrying Amount	$ 4,411	$ 4,930

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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