FAIR VALUE - Carrying Value and Fair Value of Financial Instruments (Details) - USD ($) $ in Thousands	Mar. 28, 2020	Dec. 28, 2019
Financial Instruments
Current portion of debt	$ 7,942	$ 7,942
Summit Materials, LLC
Financial Instruments
Current portion of debt	7,942	7,942
Level 2
Financial Instruments
Current portion of debt	7,900	7,900
Level 2 \| Fair Value
Financial Instruments
Long-term debt	1,699,541	1,918,720
Level 2 \| Carrying Value
Financial Instruments
Long-term debt	1,870,802	1,872,273
Level 2 \| Summit Materials, LLC
Financial Instruments
Current portion of debt		7,900
Level 2 \| Summit Materials, LLC \| Fair Value
Financial Instruments
Long-term debt	1,699,541	1,918,720
Level 2 \| Summit Materials, LLC \| Carrying Value
Financial Instruments
Long-term debt	1,870,802	1,872,273
Level 3 \| Fair Value
Financial Instruments
Current portion of deferred consideration and noncompete obligations	30,398	30,733
Long term portion of deferred consideration and noncompete obligations	11,793	18,499
Level 3 \| Carrying Value
Financial Instruments
Current portion of deferred consideration and noncompete obligations	30,398	30,733
Long term portion of deferred consideration and noncompete obligations	11,793	18,499
Level 3 \| Summit Materials, LLC \| Fair Value
Financial Instruments
Current portion of deferred consideration and noncompete obligations	28,146	28,233
Long term portion of deferred consideration and noncompete obligations	11,793	16,364
Level 3 \| Summit Materials, LLC \| Carrying Value
Financial Instruments
Current portion of deferred consideration and noncompete obligations	28,146	28,233
Long term portion of deferred consideration and noncompete obligations	$ 11,793	$ 16,364

Deferred consideration and noncompete obligations current fair value.

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- Definition

Deferred consideration and noncompete obligations noncurrent fair value.

+ References

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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

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- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19,20)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

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