Accrued Expenses - Components of Accrued Expenses (Details) - USD ($) $ in Thousands	Dec. 28, 2019	Dec. 29, 2018
Schedule Of Accrued Expenses [Line Items]
Interest	$ 26,892	$ 26,223
Payroll and benefits	29,356	15,952
Finance lease obligations	16,007
Finance lease obligations		15,557
Insurance	14,968	13,625
Non-income taxes	7,666	7,442
Professional fees	902	1,408
Other	24,214	20,284
Total	120,005	100,491
Summit Materials, LLC
Schedule Of Accrued Expenses [Line Items]
Interest	26,892	26,223
Payroll and benefits	29,356	15,952
Finance lease obligations	16,007
Finance lease obligations		15,557
Insurance	14,968	13,625
Non-income taxes	7,898	7,674
Professional fees	902	1,408
Other	24,214	19,590
Total	$ 120,237	$ 100,029

Schedule Of Accrued Expenses [Line Items]

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Carrying value as of the balance sheet date of obligations incurred and payable for real and property taxes. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Carrying value as of the balance sheet date of obligations, excluding pension and other postretirement benefits, incurred through that date and payable for perquisites provided to employees pertaining to services received from them. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Carrying value as of the balance sheet date of obligations incurred through that date and payable to insurance entities to mitigate potential loss from various risks or to satisfy a promise to provide certain coverage's to employees. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Carrying value as of the balance sheet date of obligations incurred and payable, pertaining to costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered. Examples include taxes, interest, rent and utilities. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Carrying value as of the balance sheet date of obligations incurred through that date and payable for professional fees, such as for legal and accounting services received. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Amount of capital lease obligation due within one year or the normal operating cycle, if longer.

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Present value of lessee's discounted obligation for lease payments from finance lease, classified as current.

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Carrying value as of the balance sheet date of [accrued] interest payable on all forms of debt, including trade payables, that has been incurred and is unpaid. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Amount of expenses incurred but not yet paid classified as other, due within one year or the normal operating cycle, if longer.

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