Unaudited Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Oct. 02, 2021	Sep. 26, 2020
Cash flow from operating activities:
Net income	$ 109,891	$ 104,930
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, depletion, amortization and accretion	177,841	164,397
Share-based compensation expense	14,875	23,119
Net gain on asset and business disposals	(19,295)	(5,746)
Non-cash loss on debt financings	2,116	4,064
Change in deferred tax asset, net	19,814	(28,968)
Other	(586)	760
Decrease (increase) in operating assets, net of acquisitions and dispositions:
Accounts receivable, net	(78,108)	(48,361)
Inventories	(12,002)	(2,829)
Costs and estimated earnings in excess of billings	(26,969)	(30,912)
Other current assets	(2,556)	(75)
Other assets	6,459	8,367
(Decrease) increase in operating liabilities, net of acquisitions and dispositions:
Accounts payable	33,756	21,729
Accrued expenses	(15,598)	3,164
Billings in excess of costs and estimated earnings	(2,907)	395
Tax receivable agreement liability	9,191	993
Other liabilities	(8,549)	3,012
Net cash provided by operating activities	207,373	218,039
Cash flow from investing activities:
Acquisitions, net of cash acquired	(7,263)	(123,195)
Purchases of property, plant and equipment	(170,070)	(140,006)
Proceeds from the sale of property, plant and equipment	8,827	8,848
Proceeds from sale of businesses	103,649	0
Other	(459)	1,395
Net cash used in investing activities	(65,316)	(252,958)
Cash flow from financing activities:
Proceeds from debt issuances	0	700,000
Financing costs	0	(9,565)
Payments on debt	(323,802)	(666,892)
Payments on acquisition-related liabilities	(9,755)	(10,391)
Proceeds from stock option exercises	32,416	329
Other	(951)	(908)
Net cash (used in) provided by financing activities	(302,092)	12,573
Impact of foreign currency on cash	(63)	(216)
Net decrease in cash	(160,098)	(22,562)
Cash and cash equivalents—beginning of period	418,181	311,319
Cash and cash equivalents—end of period	258,083	288,757
Summit Materials, LLC
Cash flow from operating activities:
Net income	130,900	84,716
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, depletion, amortization and accretion	177,779	164,155
Share-based compensation expense	14,875	23,119
Net gain on asset and business disposals	(19,295)	(5,746)
Non-cash loss on debt financings	2,116	4,064
Change in deferred tax asset, net	8,058	(7,519)
Other	(586)	760
Decrease (increase) in operating assets, net of acquisitions and dispositions:
Accounts receivable, net	(78,108)	(48,361)
Inventories	(12,002)	(2,829)
Costs and estimated earnings in excess of billings	(26,969)	(30,912)
Other current assets	(2,556)	(75)
Other assets	6,459	8,367
(Decrease) increase in operating liabilities, net of acquisitions and dispositions:
Accounts payable	33,756	21,729
Accrued expenses	(15,598)	3,164
Billings in excess of costs and estimated earnings	(2,907)	395
Other liabilities	(8,549)	3,012
Net cash provided by operating activities	207,373	218,039
Cash flow from investing activities:
Acquisitions, net of cash acquired	(7,263)	(123,195)
Purchases of property, plant and equipment	(170,070)	(140,006)
Proceeds from the sale of property, plant and equipment	8,827	8,848
Proceeds from sale of businesses	103,649	0
Other	(459)	1,395
Net cash used in investing activities	(65,316)	(252,958)
Cash flow from financing activities:
Capital contributions by member	32,416	329
Proceeds from debt issuances	0	700,000
Financing costs	0	(9,565)
Payments on debt	(323,802)	(666,892)
Payments on acquisition-related liabilities	(7,255)	(7,891)
Distributions	(2,500)	(2,500)
Other	(951)	(908)
Net cash (used in) provided by financing activities	(302,092)	12,573
Impact of foreign currency on cash	(63)	(216)
Net decrease in cash	(160,098)	(22,562)
Cash and cash equivalents—beginning of period	418,181	311,319
Cash and cash equivalents—end of period	$ 258,083	$ 288,757