Revenue Recognition - Summary of Accounts Receivable, Net (Details) - USD ($) $ in Thousands	9 Months Ended
Sep. 29, 2018	Dec. 30, 2017
Accounts, Notes, Loans and Financing Receivable [Line Items]
Trade accounts receivable	$ 220,540	$ 137,696
Construction contract receivables	70,626	49,832
Retention receivables	15,144	14,973
Receivables from related parties	297	468
Accounts receivable	306,607	202,969
Less: Allowance for doubtful accounts	(4,937)	(4,639)
Accounts receivable, net	$ 301,670	198,330
Maximum
Accounts, Notes, Loans and Financing Receivable [Line Items]
General collection and billing period for retention receivables	1 year
Summit Materials, LLC
Accounts, Notes, Loans and Financing Receivable [Line Items]
Trade accounts receivable	$ 220,540	137,696
Construction contract receivables	70,626	49,832
Retention receivables	15,144	14,973
Receivables from related parties	297	468
Accounts receivable	306,607	202,969
Less: Allowance for doubtful accounts	(4,937)	(4,639)
Accounts receivable, net	$ 301,670	$ 198,330
Summit Materials, LLC \| Maximum
Accounts, Notes, Loans and Financing Receivable [Line Items]
General collection and billing period for retention receivables	1 year

The general collection and billing period for retention receivables.

No definition available.

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- Definition

Amounts earned by entity but held by customers until projects have been fully completed or near completion and are expected to be billed and collected within one year of the balance sheet date (or the normal operating cycle, whichever is longer).

+ References

No definition available.

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- Definition

Trade receivable amounts due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer) for goods or services.

+ References

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Amounts due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer) for goods or services (including trade receivables) that have been delivered or sold in the normal course of business.

+ References

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- Definition

Amount due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer), for goods or services (including trade receivables) that have been delivered or sold in the normal course of business, reduced to the estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.

+ References

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- Definition

For an unclassified balance sheet, amount of receivables arising from transactions with related parties.

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- Definition

A valuation allowance for trade and other receivables due to an Entity within one year (or the normal operating cycle, whichever is longer) that are expected to be uncollectible.

+ References

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- Definition

Amounts due for billed services rendered or to be rendered, actions taken or to be taken, or a promise to refrain from taking certain actions in accordance with the terms of a legally binding agreement between the Company and, at a minimum, one other party. An example would be amounts billed to customers under contracts or programs but not paid as of the balance sheet date.

+ References

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