Number of plants owned and operated by the entity.

No definition available.

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- Definition

Percentage of benefits related to tax receivable agreement paid by entity.

+ References

No definition available.

+ Details

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- Definition

Revenue From Contract With Customer, Collection Terms

+ References

No definition available.

+ Details

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- Definition

The percentage of the the subsidiary's voting power that is controlled by the parent registrant.

+ References

No definition available.

+ Details

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- Definition

Summary Of Significant Accounting Policies And Recent Accounting Pronouncements [Line Items]

+ References

No definition available.

+ Details

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- Definition

The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

+ References

No definition available.

+ Details

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- Definition

Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 18
-URI https://asc.fasb.org/extlink&oid=126901519&loc=d3e8672-108599

+ Details

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- Definition

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

+ References

+ Details

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- Definition

The number of states the entity operates in as of the balance sheet date.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
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Summary of Organization and Significant Accounting Policies - General Information and Equity Offerings (Details)	12 Months Ended
	Dec. 31, 2022 segment state cementPlant	Jan. 02, 2021
Summary Of Significant Accounting Policies And Recent Accounting Pronouncements
Number of operating segments	3
Number of reportable segments	3
Number of states in which the entity operates \| state	22
Summit Materials, LLC
Summary Of Significant Accounting Policies And Recent Accounting Pronouncements
Number of operating segments	3
Number of reportable segments	3
Number of states in which the entity operates \| state	22
Summit Materials, LLC \| Ohio Valley Asphalt
Summary Of Significant Accounting Policies And Recent Accounting Pronouncements
Ownership percentage by non controlling owners	20.00%
Summit Materials, LLC \| Continental Cement
Summary Of Significant Accounting Policies And Recent Accounting Pronouncements
Ownership percentage by non controlling owners	30.00%
Summit Holdings LP
Summary Of Significant Accounting Policies And Recent Accounting Pronouncements
Voting power (as a percent)		100.00%
Cement Plant
Summary Of Significant Accounting Policies And Recent Accounting Pronouncements
Number of plants \| cementPlant	2
Cement Plant \| Summit Materials, LLC
Summary Of Significant Accounting Policies And Recent Accounting Pronouncements
Number of plants \| cementPlant	2
Tax Receivable Agreement \| Summit Holdings LP
Summary Of Significant Accounting Policies And Recent Accounting Pronouncements
Percentage of benefits to be paid on tax receivable agreement	85.00%
Minimum \| Product
Summary Of Significant Accounting Policies And Recent Accounting Pronouncements
Collection terms	30 days
Minimum \| Product \| Summit Materials, LLC
Summary Of Significant Accounting Policies And Recent Accounting Pronouncements
Collection terms	30 days
Maximum \| Product
Summary Of Significant Accounting Policies And Recent Accounting Pronouncements
Collection terms	60 days
Maximum \| Product \| Summit Materials, LLC
Summary Of Significant Accounting Policies And Recent Accounting Pronouncements
Collection terms	60 days
Maximum \| Service
Summary Of Significant Accounting Policies And Recent Accounting Pronouncements
Collection terms	90 days
Maximum \| Service \| Summit Materials, LLC
Summary Of Significant Accounting Policies And Recent Accounting Pronouncements
Collection terms	90 days