ACQUISITIONS, DISPOSTIONS, GOODWILL AND INTANGIBLES - Amortization Expense (Details) - USD ($) $ in Thousands	3 Months Ended
Apr. 02, 2022	Apr. 03, 2021	Jan. 01, 2022
Business Acquisition [Line Items]
Amortization expense	$ 900	$ 1,000
Estimated amortization expense
2022 (nine months)	2,830
2023	3,780
2024	3,754
2025	3,710
2026	3,661
2027	3,649
Thereafter	45,631
Total	67,015		$ 69,396
Summit Materials, LLC
Business Acquisition [Line Items]
Amortization expense	900	$ 1,000
Estimated amortization expense
2022 (nine months)	2,830
2023	3,780
2024	3,754
2025	3,710
2026	3,661
2027	3,649
Thereafter	45,631
Total	$ 67,015		$ 69,396

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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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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