Represents the required quarterly principal repayments of debt as a percent.

No definition available.

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- Definition

Percentage points added to the base rate to determine reference rate.

+ References

No definition available.

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- Definition

First lien leverage ratio as defined in the terms of the agreement.

+ References

No definition available.

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- Definition

Amount of amortization expense attributable to debt issuance costs.

+ References

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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- Definition

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.

+ References

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Balance Type:	credit
Period Type:	instant

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

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-Publisher FASB
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+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- 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.

+ Details

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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

+ Details

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Period Type:	instant

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

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- Details

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Debt - Senior Secured Credit Facilities - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 30, 2017	Dec. 31, 2016	Nov. 21, 2017	Jan. 19, 2017
Debt
Outstanding principal amount	$ 1,835,375
Term Loan, due 2024
Debt
Outstanding principal amount	635,400	$ 640,300
Summit Materials, LLC
Debt
Outstanding principal amount	1,835,375
Financing fees recognized	$ 3,990	3,403
Summit Materials, LLC \| Senior Secured Credit Facilities
Debt
First lien leverage ratio	4.75
Summit Materials, LLC \| Term Loan, due 2022
Debt
Outstanding principal amount				$ 640,300
Summit Materials, LLC \| Term Loan, due 2024
Debt
Debt instrument, face amount	$ 650,000
Outstanding principal amount	635,400	$ 640,300	$ 635,400
Summit Materials, LLC \| Revolving Credit Facility
Debt
Maximum borrowing capacity	$ 235,000
Quarterly principal repayments percentage	0.25%
Remaining borrowing capacity	$ 218,900
Summit Materials, LLC \| Revolving Credit Facility \| LIBOR
Debt
Basis spread on variable rate	3.25%
Summit Materials, LLC \| Revolving Credit Facility \| LIBOR Plus 1%
Debt
Basis spread on variable rate	2.25%
Percentage added to base rate	1.00%
Summit Materials, LLC \| Revolving Credit Facility \| Federal funds rate
Debt
Basis spread on variable rate	0.50%
Summit Materials, LLC \| Letter of Credit
Debt
Amount outstanding	$ 16,100