Supplemental Cash Flow Information - Schedule of Supplemental Cash Flow Information (Details) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2017	Oct. 01, 2016
Cash payments:
Interest	$ 71,117	$ 62,438
Income taxes	1,841	1,536
Non cash financing activities:
Exchange of LP units to Common A Stock	34,831	525,711
Summit Materials, LLC
Cash payments:
Interest	71,117	62,438
Income taxes	$ 1,841	$ 1,536

Non Cash Financing Activities [Abstract]

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The value of the stock converted in a noncash (or part noncash) transaction. Noncash is defined as transactions during a period that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4313-108586

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 5
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4304-108586

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- Definition

The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4297-108586

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 25
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3536-108585

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- Definition

The amount of cash paid for interest during the period net of cash paid for interest that is capitalized.

+ References

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- References

No definition available.

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