The number of limited partner units exchanged.

No definition available.

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- Definition

Represents other stockholder equity activity, in shares.

+ References

No definition available.

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- Definition

Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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-Publisher FASB
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-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(29))
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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

The number of limited partner units outstanding.

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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-Paragraph 5
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- Definition

The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

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No definition available.

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- Definition

The number of shares issued during the period upon the conversion of units. An example of a convertible unit is an umbrella partnership real estate investment trust unit (UPREIT unit).

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Number of share options (or share units) exercised during the current period.

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Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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STOCKHOLDERS' EQUITY/MEMBERS' INTEREST - Equity Offerings (Details) - shares	3 Months Ended
	Apr. 02, 2022	Apr. 03, 2021	Jan. 01, 2022	Jan. 02, 2021
Common Class A
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance (in shares)	118,705,108	114,390,595
Exchanges during period (in shares)		711,794
Stock option exercises (in shares)	1,589	863,338
Repurchases of common stock (in shares)	(1,506,878)
Other equity transactions (in shares)	842,029	678,605
Ending balance (in shares)	118,041,848	116,644,332
Summit Materials, Inc. and Summit Holdings, LP
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance (in shares)	120,019,114	117,263,765
Exchanges during period (in shares)		0
Stock option exercises (in shares)	1,589	863,338
Repurchases of common stock (in shares)	(1,506,878)
Other equity transactions (in shares)	842,029	678,605
Ending balance (in shares)	119,355,854	118,805,708
LP Units \| Summit Holdings LP
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Number of LP Units outstanding, beginning balance (in shares)	1,314,006	2,873,170
Number of LP Units exchanged (in shares)		(711,794)
Number of LP Units outstanding, ending balance (in shares)	1,314,006	2,161,376
Summit Materials Inc
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Ownership percentage	98.90%	98.20%	98.90%	97.50%