Fair Value of Financial Instruments - Carrying Value and Fair Value of Financial Instruments (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Jan. 01, 2022
Financial Instruments
Current portion of debt	$ 5,096	$ 6,354
Summit Materials, LLC
Financial Instruments
Current portion of debt	5,096	6,354
Level 1 \| Fair Value
Financial Instruments
Long-term debt	1,447,673	1,653,085
Current portion of debt	5,100	6,400
Level 1 \| Carrying Value
Financial Instruments
Long-term debt	1,504,549	1,609,298
Level 1 \| Summit Materials, LLC
Financial Instruments
Current portion of debt	5,100	6,400
Level 1 \| Summit Materials, LLC \| Fair Value
Financial Instruments
Long-term debt	1,447,673	1,653,085
Level 1 \| Summit Materials, LLC \| Carrying Value
Financial Instruments
Long-term debt	1,504,549	1,609,298
Level 3 \| Fair Value
Financial Instruments
Current portion of deferred consideration and noncompete obligations	13,382	12,981
Long term portion of deferred consideration and noncompete obligations	24,070	32,130
Level 3 \| Carrying Value
Financial Instruments
Current portion of deferred consideration and noncompete obligations	13,382	12,981
Long term portion of deferred consideration and noncompete obligations	24,070	32,130
Level 3 \| Summit Materials, LLC \| Fair Value
Financial Instruments
Current portion of deferred consideration and noncompete obligations	13,382	12,981
Long term portion of deferred consideration and noncompete obligations	24,070	32,130
Level 3 \| Summit Materials, LLC \| Carrying Value
Financial Instruments
Current portion of deferred consideration and noncompete obligations	13,382	12,981
Long term portion of deferred consideration and noncompete obligations	$ 24,070	$ 32,130

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 https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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- Definition

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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