Unaudited Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 26, 2020	Sep. 28, 2019
Cash flow from operating activities:
Net income	$ 104,930	$ 24,726
Adjustments to reconcile net income to net cash used in operating activities:
Depreciation, depletion, amortization and accretion	164,397	166,997
Share-based compensation expense	23,119	15,424
Net gain on asset disposals	(5,746)	(8,030)
Non-cash loss on debt financings	4,064	2,850
Change in deferred tax asset, net	(28,968)	32,736
Other	760	(1,609)
Decrease (increase) in operating assets, net of acquisitions and dispositions:
Accounts receivable, net	(48,361)	(121,196)
Inventories	(2,829)	16,296
Costs and estimated earnings in excess of billings	(30,912)	(31,085)
Other current assets	(75)	5,635
Other assets	8,367	4,992
(Decrease) increase in operating liabilities, net of acquisitions and dispositions:
Accounts payable	21,729	52,423
Accrued expenses	3,164	8,447
Billings in excess of costs and estimated earnings	395	618
Tax receivable agreement liability	993	424
Other liabilities	3,012	(5,805)
Net cash provided by operating activities	218,039	163,843
Cash flow from investing activities:
Acquisitions, net of cash acquired	(123,195)	(2,842)
Purchases of property, plant and equipment	(140,006)	(139,762)
Proceeds from the sale of property, plant and equipment	8,848	13,035
Other	1,395	(207)
Net cash used for investing activities	(252,958)	(129,776)
Cash flow from financing activities:
Proceeds from debt issuances	700,000	300,000
Debt issuance costs	(9,565)	(6,312)
Payments on debt	(666,892)	(264,906)
Payments on acquisition-related liabilities	(10,391)	(11,000)
Proceeds from stock option exercises	329	2,559
Other	(908)	(501)
Net cash provided by financing activities	12,573	19,840
Impact of foreign currency on cash	(216)	174
Net (decrease) increase in cash	(22,562)	54,081
Cash and cash equivalents—beginning of period	311,319	128,508
Cash and cash equivalents—end of period	288,757	182,589
Summit Materials, LLC
Cash flow from operating activities:
Net income	84,716	47,136
Adjustments to reconcile net income to net cash used in operating activities:
Depreciation, depletion, amortization and accretion	164,155	166,594
Share-based compensation expense	23,119	15,424
Net gain on asset disposals	(5,746)	(8,030)
Non-cash loss on debt financings	4,064	2,850
Change in deferred tax asset, net	(7,519)	11,153
Other	760	(1,609)
Decrease (increase) in operating assets, net of acquisitions and dispositions:
Accounts receivable, net	(48,361)	(121,196)
Inventories	(2,829)	16,296
Costs and estimated earnings in excess of billings	(30,912)	(31,085)
Other current assets	(75)	5,635
Other assets	8,367	4,992
(Decrease) increase in operating liabilities, net of acquisitions and dispositions:
Accounts payable	21,729	51,728
Accrued expenses	3,164	9,142
Billings in excess of costs and estimated earnings	395	618
Other liabilities	3,012	(5,805)
Net cash provided by operating activities	218,039	163,843
Cash flow from investing activities:
Acquisitions, net of cash acquired	(123,195)	(2,842)
Purchases of property, plant and equipment	(140,006)	(139,762)
Proceeds from the sale of property, plant and equipment	8,848	13,035
Other	1,395	(207)
Net cash used for investing activities	(252,958)	(129,776)
Cash flow from financing activities:
Capital contributions by member	329	2,559
Proceeds from debt issuances	700,000	300,000
Debt issuance costs	(9,565)	(6,312)
Payments on debt	(666,892)	(264,906)
Payments on acquisition-related liabilities	(7,891)	(8,500)
Distributions from partnership	(2,500)	(2,500)
Other	(908)	(501)
Net cash provided by financing activities	12,573	19,840
Impact of foreign currency on cash	(216)	174
Net (decrease) increase in cash	(22,562)	54,081
Cash and cash equivalents—beginning of period	311,319	128,508
Cash and cash equivalents—end of period	$ 288,757	$ 182,589