Income Taxes - Components of Income Tax Benefit (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2022	Jan. 01, 2022	Jan. 02, 2021
Provision for income taxes:
Current	$ 15,654	$ 8,030	$ 3,827
Deferred	69,891	36,326	(16,012)
Income tax expense (benefit)	85,545	44,356	(12,185)
Summit Materials, LLC
Provision for income taxes:
Current	16,280	8,459	3,827
Deferred	305	12,490	(2,764)
Income tax expense (benefit)	$ 16,585	$ 20,949	$ 1,063

Amount of deferred income tax expense (benefit) pertaining to income (loss) from continuing operations.

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration