Debt - Schedule of Debt (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Jan. 01, 2022
Debt
Total debt	$ 1,504,549	$ 1,609,298
Current portion of long-term debt	5,096	6,354
Long-term debt	1,499,453	1,602,944
Gross amount	1,509,560
Debt discount	5,011
Summit Materials, LLC
Debt
Total debt	1,504,549	1,609,298
Current portion of long-term debt	5,096	6,354
Long-term debt	1,499,453	1,602,944
Gross amount	1,509,560
Debt discount	5,011
Term Loan, due 2027:
Debt
Total debt	504,549	609,298
Gross amount	509,600	610,000
Debt discount	5,000	700
Term Loan, due 2027: \| Summit Materials, LLC
Debt
Total debt	504,549	609,298
Gross amount	509,600	610,000
Debt discount	5,000	700
Senior Notes \| 6 1⁄2% Senior Notes, due 2027
Debt
Total debt	300,000	300,000
Senior Notes \| 6 1⁄2% Senior Notes, due 2027 \| Summit Materials, LLC
Debt
Total debt	300,000	300,000
Senior Notes \| 5 1⁄4% Senior Notes, due 2029
Debt
Total debt	700,000	700,000
Senior Notes \| 5 1⁄4% Senior Notes, due 2029 \| Summit Materials, LLC
Debt
Total debt	$ 700,000	$ 700,000

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Amount, after accumulated amortization, of debt discount.

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Amount, excluding unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount, excluding unamortized premium (discount) and debt issuance cost, of long-term debt classified as noncurrent. Excludes lease obligation.

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