Summit Materials (SUM) 10-Q 1 Aug 19 2019 Q2 Quarterly report Financial data

Cover

Cover - shares	6 Months Ended
	Jun. 29, 2019	Jul. 29, 2019
Document Information [Line Items]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Jun. 29, 2019
Document Transition Report	false
Entity File Number	001-36873
Entity Registrant Name	SUMMIT MATERIALS, INC.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	47-1984212
Entity Address, Address Line One	1550 Wynkoop Street
Entity Address, Address Line Two	3rd Floor
Entity Address, City or Town	Denver
Entity Address, State or Province	CO
Entity Address, Postal Zip Code	80202
City Area Code	303
Local Phone Number	893-0012
Title of 12(b) Security	Class A Common Stock (par value $.01 per share)
Trading Symbol	SUM
Security Exchange Name	NYSE
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Central Index Key	0001621563
Amendment Flag	false
Current Fiscal Year End Date	--12-28
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	Q2
Common Class A
Document Information [Line Items]
Entity common stock, shares outstanding (in shares)		112,074,156
Class B Common Stock
Document Information [Line Items]
Entity common stock, shares outstanding (in shares)		99
Summit Materials, LLC
Document Information [Line Items]
Entity File Number	333-187556
Entity Registrant Name	SUMMIT MATERIALS, LLC
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	26-4138486
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Shell Company	false
Entity Central Index Key	0001571371
Amendment Flag	false
Current Fiscal Year End Date	--12-28
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	Q2

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Jun. 29, 2019	Dec. 29, 2018
Current assets:
Cash and cash equivalents	$ 67,658	$ 128,508
Accounts receivable, net	294,604	214,518
Costs and estimated earnings in excess of billings	45,371	18,602
Inventories	208,136	213,851
Other current assets	12,618	16,061
Total current assets	628,387	591,540
Property, plant and equipment, less accumulated depreciation, depletion and amortization (June 29, 2019 - $881,606 and December 29, 2018 - $794,251)	1,788,664	1,780,132
Goodwill	1,198,177	1,192,028
Intangible assets, less accumulated amortization (June 29, 2019 - $9,054 and December 29, 2018 - $8,247)	17,653	18,460
Deferred tax assets, less valuation allowance (June 29, 2019 - $27,863 and December 29, 2018 - $19,366)	237,089	225,397
Operating lease right-of-use assets	34,101
Other assets	50,785	50,084
Total assets	3,954,856	3,857,641
Current liabilities:
Current portion of debt	4,765	6,354
Current portion of acquisition-related liabilities	35,470	34,270
Accounts payable	131,391	107,702
Accrued expenses	113,996	100,491
Current operating lease liabilities	8,470
Billings in excess of costs and estimated earnings	10,733	11,840
Total current liabilities	304,825	260,657
Long-term debt	1,854,189	1,807,502
Acquisition-related liabilities	40,088	49,468
Tax receivable agreement liability	309,733	309,674
Noncurrent operating lease liabilities	26,614
Other noncurrent liabilities	96,636	88,195
Total liabilities	2,632,085	2,515,496
Commitments and contingencies (see note 12)
Stockholders’ equity:
Additional paid-in capital	1,205,221	1,194,204
Accumulated earnings	97,377	129,739
Accumulated other comprehensive income	5,791	2,681
Stockholders’ equity	1,309,511	1,327,741
Noncontrolling interest in Summit Holdings	13,260	14,404
Total stockholders’ equity	1,322,771	1,342,145
Total liabilities and stockholders’ equity/member's interest	3,954,856	3,857,641
Summit Materials, LLC
Current assets:
Cash and cash equivalents	67,658	128,508
Accounts receivable, net	294,604	214,518
Costs and estimated earnings in excess of billings	45,371	18,602
Inventories	208,136	213,851
Other current assets	12,618	16,061
Total current assets	628,387	591,540
Property, plant and equipment, less accumulated depreciation, depletion and amortization (June 29, 2019 - $881,606 and December 29, 2018 - $794,251)	1,788,664	1,780,132
Goodwill	1,199,177	1,193,028
Intangible assets, less accumulated amortization (June 29, 2019 - $9,054 and December 29, 2018 - $8,247)	17,653	18,460
Operating lease right-of-use assets	34,101
Other assets	50,785	50,084
Total assets	3,718,767	3,633,244
Current liabilities:
Current portion of debt	4,765	6,354
Current portion of acquisition-related liabilities	32,970	31,770
Accounts payable	132,002	109,008
Accrued expenses	114,228	100,029
Current operating lease liabilities	8,470
Billings in excess of costs and estimated earnings	10,733	11,840
Total current liabilities	303,168	259,001
Long-term debt	1,854,189	1,807,502
Acquisition-related liabilities	38,189	45,354
Noncurrent operating lease liabilities	26,614
Other noncurrent liabilities	136,563	135,956
Total liabilities	2,358,723	2,247,813
Commitments and contingencies (see note 12)
Stockholders’ equity:
Members' equity	1,404,629	1,396,241
Accumulated earnings	(25,257)	12,806
Accumulated other comprehensive income	(19,328)	(23,616)
Total member's interest	1,360,044	1,385,431
Total liabilities and stockholders’ equity/member's interest	3,718,767	3,633,244
Common Class A
Stockholders’ equity:
Common stock	1,122	1,117
Class B Common Stock
Stockholders’ equity:
Common stock	$ 0	$ 0

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Jun. 29, 2019	Dec. 29, 2018
Property, plant and equipment, less accumulated depreciation, depletion and amortization (June 29, 2019 - $881,606 and December 29, 2018 - $794,251)	$ 881,606	$ 794,251
Intangible assets, less accumulated amortization (June 29, 2019 - $9,054 and December 29, 2018 - $8,247)	9,054	8,247
Deferred tax assets, less valuation allowance (June 29, 2019 - $27,863 and December 29, 2018 - $19,366)	27,863	19,366
Summit Materials, LLC
Property, plant and equipment, less accumulated depreciation, depletion and amortization (June 29, 2019 - $881,606 and December 29, 2018 - $794,251)	881,606	794,251
Intangible assets, less accumulated amortization (June 29, 2019 - $9,054 and December 29, 2018 - $8,247)	$ 9,054	$ 8,247
Common Class A
Common stock, par value (usd per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	1,000,000,000	1,000,000,000
Common stock, shares issued (in shares)	112,073,494	111,658,927
Common stock, shares outstanding (in shares)	112,073,494	111,658,927
Class B Common Stock
Common stock, par value (usd per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	250,000,000	250,000,000
Common stock, shares issued (in shares)	99	99
Common stock, shares outstanding (in shares)	99	99

Unaudited Consolidated Statemen

Unaudited Consolidated Statements of Operations - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 29, 2019	Jun. 30, 2018	Jun. 29, 2019	Jun. 30, 2018
Revenue:
Revenue	$ 600,891	$ 600,890	$ 933,530	$ 915,311
Cost of revenue (excluding items shown separately below):
Net cost of revenue	405,493	410,932	672,497	658,793
General and administrative expenses	60,961	61,657	128,571	131,518
Depreciation, depletion, amortization and accretion	53,625	49,731	109,013	96,689
Transaction costs	390	1,291	698	2,557
Operating income	80,422	77,279	22,751	25,754
Interest expense	29,401	28,943	59,506	57,727
Loss on debt financings	0	149	14,565	149
Other income, net	(3,676)	(916)	(6,479)	(8,571)
Income (loss) from operation before taxes	54,697	49,103	(44,841)	(23,551)
Income tax expense (benefit)	16,707	12,190	(11,330)	(4,516)
Net income (loss)	37,990	36,913	(33,511)	(19,035)
Net income (loss) attributable to Summit Holdings	1,580	1,404	(1,149)	(815)
Net income (loss) attributable to Summit Inc.	36,410	35,509	(32,362)	(18,220)
Summit Materials, LLC
Revenue:
Revenue	600,891	600,890	933,530	915,311
Cost of revenue (excluding items shown separately below):
Net cost of revenue	405,493	410,932	672,497	658,793
General and administrative expenses	60,961	61,657	128,571	131,518
Depreciation, depletion, amortization and accretion	53,625	49,731	109,013	96,689
Transaction costs	390	1,291	698	2,557
Operating income	80,422	77,279	22,751	25,754
Interest expense	29,283	28,776	59,220	57,346
Loss on debt financings	0	149	14,565	149
Other income, net	(3,676)	(916)	(6,479)	(8,571)
Income (loss) from operation before taxes	54,815	49,270	(44,555)	(23,170)
Income tax expense (benefit)	1,314	2,668	(6,492)	(1,176)
Net income (loss)	53,501	46,602	(38,063)	(21,994)
Net income (loss) attributable to Summit Inc.	$ 53,501	$ 46,602	$ (38,063)	$ (21,994)
Common Class A
Income (loss) per share of Class A common stock:
Basic (usd per share)	$ 0.32	$ 0.32	$ (0.29)	$ (0.16)
Diluted (usd per share)	$ 0.32	$ 0.32	$ (0.29)	$ (0.16)
Weighted average shares of Class A common stock:
Basic (in shares)	112,070,009	111,564,190	111,940,844	111,111,644
Diluted (in shares)	112,182,555	112,583,321	111,940,844	111,111,644
Product
Revenue:
Revenue	$ 467,637	$ 459,967	$ 739,278	$ 716,774
Cost of revenue (excluding items shown separately below):
Net cost of revenue	294,857	295,147	508,583	492,580
Product | Summit Materials, LLC
Revenue:
Revenue	467,637	459,967	739,278	716,774
Cost of revenue (excluding items shown separately below):
Net cost of revenue	294,857	295,147	508,583	492,580
Service
Revenue:
Revenue	84,954	89,268	119,263	122,377
Cost of revenue (excluding items shown separately below):
Net cost of revenue	62,336	64,130	88,925	90,053
Service | Summit Materials, LLC
Revenue:
Revenue	84,954	89,268	119,263	122,377
Cost of revenue (excluding items shown separately below):
Net cost of revenue	62,336	64,130	88,925	90,053
Excluding delivery and subcontract revenue
Revenue:
Revenue	552,591	549,235	858,541	839,151
Cost of revenue (excluding items shown separately below):
Net cost of revenue	357,193	359,277	597,508	582,633
Excluding delivery and subcontract revenue | Summit Materials, LLC
Revenue:
Revenue	552,591	549,235	858,541	839,151
Cost of revenue (excluding items shown separately below):
Net cost of revenue	357,193	359,277	597,508	582,633
Delivery and subcontract revenue
Revenue:
Revenue	48,300	51,655	74,989	76,160
Cost of revenue (excluding items shown separately below):
Net cost of revenue	48,300	51,655	74,989	76,160
Delivery and subcontract revenue | Summit Materials, LLC
Revenue:
Revenue	48,300	51,655	74,989	76,160
Cost of revenue (excluding items shown separately below):
Net cost of revenue	$ 48,300	$ 51,655	$ 74,989	$ 76,160

Unaudited Consolidated Statem_2

Unaudited Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 29, 2019	Jun. 30, 2018	Jun. 29, 2019	Jun. 30, 2018
Comprehensive income (loss)
Net income (loss)	$ 37,990	$ 36,913	$ (33,511)	$ (19,035)
Other comprehensive income (loss):
Foreign currency translation adjustment	2,233	(2,045)	4,591	(5,149)
(Loss) income on cash flow hedges	(137)	361	(303)	1,356
Less tax effect of other comprehensive (loss) income items	(508)	1,455	(1,050)	935
Other comprehensive income (loss)	1,588	(229)	3,238	(2,858)
Comprehensive income (loss)	39,578	36,684	(30,273)	(21,893)
Less comprehensive income (loss) attributable to Summit Holdings	1,576	1,353	(1,087)	(932)
Comprehensive income (loss) attributable to Summit Inc.	38,002	35,331	(29,186)	(20,961)
Summit Materials, LLC
Comprehensive income (loss)
Net income (loss)	53,501	46,602	(38,063)	(21,994)
Other comprehensive income (loss):
Foreign currency translation adjustment	2,233	(2,045)	4,591	(5,149)
(Loss) income on cash flow hedges	(137)	361	(303)	1,356
Other comprehensive income (loss)	2,096	(1,684)	4,288	(3,793)
Comprehensive income (loss) attributable to Summit Inc.	$ 55,597	$ 44,918	$ (33,775)	$ (25,787)

Unaudited Consolidated Statem_3

Unaudited Consolidated Statements of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Jun. 29, 2019	Jun. 30, 2018
Cash flow from operating activities:
Net loss	$ (33,511)	$ (19,035)
Adjustments to reconcile net loss to net cash provided by (used in) operating activities:
Depreciation, depletion, amortization and accretion	110,982	98,562
Share-based compensation expense	10,605	14,190
Net gain on asset disposals	(3,937)	(7,508)
Non-cash loss on debt financings	2,850	0
Change in deferred tax asset, net	(12,550)	(6,934)
Other	(120)	162
(Increase) decrease in operating assets, net of acquisitions and dispositions:
Accounts receivable, net	(79,320)	(57,763)
Inventories	5,208	(44,428)
Costs and estimated earnings in excess of billings	(26,715)	(34,525)
Other current assets	3,585	(1,766)
Other assets	4,374	780
(Decrease) increase in operating liabilities, net of acquisitions and dispositions:
Accounts payable	29,898	23,912
Accrued expenses	9,395	1,674
Billings in excess of costs and estimated earnings	(1,138)	(2,187)
Tax receivable agreement liability	59	1,688
Other liabilities	(3,717)	(540)
Net cash provided by (used in) operating activities	15,948	(33,718)
Cash flow from investing activities:
Acquisitions, net of cash acquired	(2,842)	(153,196)
Purchases of property, plant and equipment	(105,569)	(131,657)
Proceeds from the sale of property, plant and equipment	8,005	14,110
Other	(439)	684
Net cash used for investing activities	(100,845)	(270,059)
Cash flow from financing activities:
Proceeds from debt issuances	300,000	0
Debt issuance costs	(6,246)	(550)
Payments on debt	(261,025)	(10,772)
Payments on acquisition-related liabilities	(9,158)	(31,224)
Distributions from partnership	0	(69)
Proceeds from stock option exercises	784	15,615
Other	(502)	(1,904)
Net cash provided by (used in) financing activities	23,853	(28,904)
Impact of foreign currency on cash	194	(471)
Net decrease in cash	(60,850)	(333,152)
Cash and cash equivalents—beginning of period	128,508	383,556
Cash and cash equivalents—end of period	67,658	50,404
Summit Materials, LLC
Cash flow from operating activities:
Net loss	(38,063)	(21,994)
Adjustments to reconcile net loss to net cash provided by (used in) operating activities:
Depreciation, depletion, amortization and accretion	110,696	98,181
Share-based compensation expense	10,605	14,190
Net gain on asset disposals	(3,937)	(7,508)
Non-cash loss on debt financings	2,850	0
Change in deferred tax asset, net	(7,653)	(1,906)
Other	(120)	162
(Increase) decrease in operating assets, net of acquisitions and dispositions:
Accounts receivable, net	(79,320)	(57,763)
Inventories	5,208	(44,428)
Costs and estimated earnings in excess of billings	(26,715)	(34,525)
Other current assets	3,585	(1,766)
Other assets	4,374	780
(Decrease) increase in operating liabilities, net of acquisitions and dispositions:
Accounts payable	29,203	23,326
Accrued expenses	10,090	2,260
Billings in excess of costs and estimated earnings	(1,138)	(2,187)
Other liabilities	(3,717)	(540)
Net cash provided by (used in) operating activities	15,948	(33,718)
Cash flow from investing activities:
Acquisitions, net of cash acquired	(2,842)	(153,196)
Purchases of property, plant and equipment	(105,569)	(131,657)
Proceeds from the sale of property, plant and equipment	8,005	14,110
Other	(439)	684
Net cash used for investing activities	(100,845)	(270,059)
Cash flow from financing activities:
Capital contributions by member	784	15,615
Proceeds from debt issuances	300,000	0
Debt issuance costs	(6,246)	(550)
Payments on debt	(261,025)	(10,772)
Payments on acquisition-related liabilities	(6,658)	(28,724)
Distributions from partnership	(2,500)	(2,569)
Other	(502)	(1,904)
Net cash provided by (used in) financing activities	23,853	(28,904)
Impact of foreign currency on cash	194	(471)
Net decrease in cash	(60,850)	(333,152)
Cash and cash equivalents—beginning of period	128,508	383,556
Cash and cash equivalents—end of period	$ 67,658	$ 50,404

Unaudited Consolidated Statem_4

Unaudited Consolidated Statements of Changes in Stockholders' Equity / Members' Interest and Redeemable Noncontrolling Interest - USD ($) $ in Thousands	Total	Summit Materials, LLC	Class A Common Stock	Class B Common Stock	Members' equitySummit Materials, LLC	Accumulated Earnings (Deficit)	Accumulated Earnings (Deficit)Summit Materials, LLC	Accumulated other comprehensive income (loss)	Accumulated other comprehensive income (loss)Summit Materials, LLC	Common StockClass A Common Stock	Common StockClass B Common Stock	Additional Paid-in Capital	Noncontrolling Interest in Summit Holdings
Beginning balance at Dec. 30, 2017	$ 1,271,721					$ 95,833		$ 7,386		$ 1,104	$ 0	$ 1,154,220	$ 13,178
Beginning balance at Dec. 30, 2017		$ 1,291,594			$ 1,359,760		$ (51,031)		$ (17,135)
Beginning balance (in shares) at Dec. 30, 2017			110,350,594							110,350,594	100
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net contributed capital		15,475			15,475
Net income (loss)	(55,948)	(68,596)				(53,729)	(68,596)						(2,219)
LP Unit exchanges (in shares)										104,104
LP Unit exchanges	0									$ 1		485	(486)
Other comprehensive income, net of tax	(2,629)	(2,109)						(2,563)	(2,109)				(66)
Stock option exercises (in shares)										856,915
Stock option exercises	15,477									$ 9		15,468
Share-based compensation	8,507	8,507			8,507							8,507
Distributions from partnership	(9)												(9)
Distributions		(2,509)			(2,509)
Other (in shares)										176,960
Shares redeemed to settle taxes and other	(1,772)	(1,820)			(1,820)					$ 2		(1,774)
Ending balance at Mar. 31, 2018	1,235,347					42,104		4,823		$ 1,116	$ 0	1,176,906	10,398
Ending balance at Mar. 31, 2018		1,240,542			1,379,413		(119,627)		(19,244)
Ending balance (in shares) at Mar. 31, 2018										111,488,573	100
Beginning balance at Dec. 30, 2017	1,271,721					95,833		7,386		$ 1,104	$ 0	1,154,220	13,178
Beginning balance at Dec. 30, 2017		1,291,594			1,359,760		(51,031)		(17,135)
Beginning balance (in shares) at Dec. 30, 2017			110,350,594							110,350,594	100
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	(19,035)	(21,994)
LP Unit exchanges (in shares)			229,658
Other comprehensive income, net of tax	$ (2,858)	(3,793)
Other (in shares)	1,048,986		1,048,986
Ending balance at Jun. 30, 2018	$ 1,277,771					77,613		4,645		$ 1,117	$ 0	1,183,071	11,325
Ending balance at Jun. 30, 2018		1,291,139			1,385,092		(73,025)		(20,928)
Ending balance (in shares) at Jun. 30, 2018			111,629,238							111,629,238	100
Beginning balance at Mar. 31, 2018	1,235,347					42,104		4,823		$ 1,116	$ 0	1,176,906	10,398
Beginning balance at Mar. 31, 2018		1,240,542			1,379,413		(119,627)		(19,244)
Beginning balance (in shares) at Mar. 31, 2018										111,488,573	100
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net contributed capital		140			140
Net income (loss)	36,913	46,602				35,509	46,602						1,404
LP Unit exchanges (in shares)										125,554
LP Unit exchanges	0									$ 1		365	(366)
Other comprehensive income, net of tax	(229)	(1,684)						(178)	(1,684)				(51)
Stock option exercises	139											139
Share-based compensation	5,683	5,683			5,683							5,683
Distributions from partnership	(60)												(60)
Distributions		(60)			(60)
Other (in shares)										15,111
Shares redeemed to settle taxes and other	(22)	(84)			(84)							(22)
Ending balance at Jun. 30, 2018	1,277,771					77,613		4,645		$ 1,117	$ 0	1,183,071	11,325
Ending balance at Jun. 30, 2018		1,291,139			1,385,092		(73,025)		(20,928)
Ending balance (in shares) at Jun. 30, 2018			111,629,238							111,629,238	100
Beginning balance at Dec. 29, 2018	1,342,145					129,739		2,681		$ 1,117	$ 0	1,194,204	14,404
Beginning balance at Dec. 29, 2018		1,385,431			1,396,241		12,806		(23,616)
Beginning balance (in shares) at Dec. 29, 2018			111,658,927	99						111,658,927	99
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net contributed capital		766			766
Net income (loss)	(71,501)	(91,564)				(68,772)	(91,564)						(2,729)
LP Unit exchanges (in shares)										17,500
LP Unit exchanges	0											122	(122)
Other comprehensive income, net of tax	1,650	2,192						1,584	2,192				66
Stock option exercises (in shares)										43,142
Stock option exercises	767									$ 1		766
Share-based compensation	5,906	5,906			5,906							5,906
Distributions		(2,500)			(2,500)
Other (in shares)										347,962
Shares redeemed to settle taxes and other	(492)	(501)			(501)					$ 3		(495)
Ending balance at Mar. 30, 2019	1,278,475					60,967		4,265		$ 1,121	$ 0	1,200,503	11,619
Ending balance at Mar. 30, 2019		1,299,730			1,399,912		(78,758)		(21,424)
Ending balance (in shares) at Mar. 30, 2019										112,067,531	99
Beginning balance at Dec. 29, 2018	1,342,145					129,739		2,681		$ 1,117	$ 0	1,194,204	14,404
Beginning balance at Dec. 29, 2018		1,385,431			1,396,241		12,806		(23,616)
Beginning balance (in shares) at Dec. 29, 2018			111,658,927	99						111,658,927	99
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	(33,511)	(38,063)
LP Unit exchanges (in shares)			17,500
Other comprehensive income, net of tax	$ 3,238	4,288
Other (in shares)	397,067		397,067
Ending balance at Jun. 29, 2019	$ 1,322,771					97,377		5,791		$ 1,122	$ 0	1,205,221	13,260
Ending balance at Jun. 29, 2019		1,360,044			1,404,629		(25,257)		(19,328)
Ending balance (in shares) at Jun. 29, 2019			112,073,494	99						112,073,494	99
Beginning balance at Mar. 30, 2019	1,278,475					60,967		4,265		$ 1,121	$ 0	1,200,503	11,619
Beginning balance at Mar. 30, 2019		1,299,730			1,399,912		(78,758)		(21,424)
Beginning balance (in shares) at Mar. 30, 2019										112,067,531	99
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net contributed capital		18			18
Net income (loss)	37,990	53,501				36,410	53,501						1,580
Other comprehensive income, net of tax	1,588	2,096						1,526	2,096				62
Stock option exercises (in shares)										1,019
Stock option exercises	17									$ 0		17
Share-based compensation	4,699	4,699			4,699							4,699
Other (in shares)										4,944
Shares redeemed to settle taxes and other	2									$ 1		2	(1)
Ending balance at Jun. 29, 2019	$ 1,322,771					$ 97,377		$ 5,791		$ 1,122	$ 0	$ 1,205,221	$ 13,260
Ending balance at Jun. 29, 2019		$ 1,360,044			$ 1,404,629		$ (25,257)		$ (19,328)
Ending balance (in shares) at Jun. 29, 2019			112,073,494	99						112,073,494	99

SUMMARY OF ORGANIZATION AND SIG

SUMMARY OF ORGANIZATION AND SIGNIFICANT ACCOUNTING POLICIES	6 Months Ended
	Jun. 29, 2019
Summary Of Significant Accounting Policies And Recent Accounting Pronouncements [Line Items]
Summary of Organization and Significant Accounting Policies	SUMMARY OF ORGANIZATION AND SIGNIFICANT ACCOUNTING POLICIES Summit Materials, Inc. (“Summit Inc.” and, together with its subsidiaries, “Summit,” “we,” “us,” “our” or the “Company”) is a vertically-integrated construction materials company. The Company is engaged in the production and sale of aggregates, cement, ready-mix concrete, asphalt paving mix and concrete products and owns and operates quarries, sand and gravel pits, two cement plants, cement distribution terminals, ready-mix concrete plants, asphalt plants and landfill sites. It is also engaged in paving and related services. The Company’s three operating and reporting segments are the West, East and Cement segments. Substantially all of the Company’s construction materials, products and services are produced, consumed and performed outdoors, primarily in the spring, summer and fall. Seasonal changes and other weather-related conditions can affect the production and sales volumes of its products and delivery of services. Therefore, the financial results for any interim period are typically not indicative of the results expected for the full year. Furthermore, the Company’s sales and earnings are sensitive to national, regional and local economic conditions, weather conditions and to cyclical changes in construction spending, among other factors. Summit Inc. is a holding corporation operating and controlling all of the business and affairs of Summit Materials Holdings L.P. (“Summit Holdings”) and its subsidiaries and, through Summit Holdings, conducts its business. Summit Inc. owns the majority of the partnership interests of Summit Holdings (see Note 9, Stockholders’ Equity). Summit Materials, LLC (“Summit LLC”) an indirect wholly owned subsidiary of Summit Holdings, conducts the majority of our operations. Summit Materials Finance Corp. (“Summit Finance”), an indirect wholly owned subsidiary of Summit LLC, has jointly issued our Senior Notes as described below. Basis of Presentation —These unaudited consolidated financial statements were prepared in accordance with U.S. generally accepted accounting principles (“U.S. GAAP”) for interim financial information, without audit, pursuant to the rules and regulations of the Securities and Exchange Commission (“SEC”). Certain information and footnote disclosures typically included in financial statements prepared in accordance with U.S. GAAP have been condensed or omitted pursuant to such rules and regulations. These unaudited consolidated financial statements should be read in conjunction with the Company's audited consolidated financial statements and the notes thereto as of and for the year ended December 29, 2018 . The Company continues to follow the accounting policies set forth in those audited consolidated financial statements. Management believes that these consolidated interim financial statements include all adjustments, normal and recurring in nature, that are necessary to present fairly the financial position of the Company as of June 29, 2019 , the results of operations for the three and six months ended June 29, 2019 and June 30, 2018 and cash flows for the six months ended June 29, 2019 and June 30, 2018 . Principles of Consolidation —The consolidated financial statements include the accounts of Summit Inc. and its majority owned subsidiaries. All intercompany balances and transactions have been eliminated. As a result of the reorganization into a holding company structure (the “Reorganization”), Summit Holdings became a variable interest entity over which Summit Inc. has 100% voting power and control and for which Summit Inc. has the obligation to absorb losses and the right to receive benefits. For a summary of the changes in Summit Inc.’s ownership of Summit Holdings, see Note 9, Stockholders’ Equity. Use of Estimates —Preparation of these consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions. These estimates and the underlying assumptions affect the amounts of assets and liabilities reported, disclosures about contingent assets and liabilities and reported amounts of revenue and expenses. Such estimates include the valuation of accounts receivable, inventories, valuation of deferred tax assets, goodwill, intangibles and other long-lived assets, the tax receivable agreement ("TRA") liability, pension and other postretirement obligations and asset retirement obligations. Estimates also include revenue earned on contracts and costs to complete contracts. Most of the Company’s paving and related services are performed under fixed unit-price contracts with state and local governmental entities. Management regularly evaluates its estimates and assumptions based on historical experience and other factors, including the current economic environment. As future events and their effects cannot be determined with precision, actual results can differ significantly from estimates made. Changes in estimates, including those resulting from continuing changes in the economic environment, are reflected in the Company’s consolidated financial statements when the change in estimate occurs. Business and Credit Concentrations— The Company’s operations are conducted primarily across 23 U.S. states and in British Columbia, Canada, with the most significant revenue generated in Texas, Utah, Kansas and Missouri. The Company’s accounts receivable consist primarily of amounts due from customers within these areas. Therefore, collection of these accounts is dependent on the economic conditions in the aforementioned states, as well as specific situations affecting individual customers. Credit granted within the Company’s trade areas has been granted to many customers, and management does not believe that a significant concentration of credit exists with respect to any individual customer or group of customers. No single customer accounted for more than 10% of the Company’s total revenue in the three and six months ended June 29, 2019 or June 30, 2018 . Revenue Recognition —We earn revenue from the sale of products, which primarily include aggregates, cement, ready-mix concrete and asphalt, but also include concrete products and plastics components, and from the provision of services, which are primarily paving and related services, but also include landfill operations, the receipt and disposal of waste that is converted to fuel for use in our cement plants and underground storage space rental. Products We earn revenue from the sale of products, which primarily include aggregates, cement, ready-mix concrete and asphalt, but also include concrete products, net of discounts or allowances, if any, and freight and delivery charges billed to customers. Freight and delivery charges associated with cement sales are recorded on a net basis together with freight costs within cost of sales. Revenue for product sales is recognized when evidence of an arrangement exists and when control passes, which generally is when the product is shipped. Services We earn revenue from the provision of services, which are primarily paving and related services, but also include landfill operations, the receipt and disposal of waste that is converted to fuel for use in our cement plants, and underground storage space rental. Revenue from the receipt of waste fuels is recognized when the waste is accepted and a corresponding liability is recognized for the costs to process the waste into fuel for the manufacturing of cement or to ship the waste offsite for disposal in accordance with applicable regulations. Revenue derived from paving and related services is recognized using the percentage of completion method, which approximates progress towards completion. Under the percentage of completion method, we recognize paving and related services revenue as services are rendered. The majority of our construction service contracts are completed within one year, but may occasionally extend beyond this time frame. We estimate profit as the difference between total estimated revenue and total estimated cost of a contract and recognize that profit over the life of the contract based on input measures. We generally measure progress toward completion on long-term paving and related services contracts based on the proportion of costs incurred to date relative to total estimated costs at completion. We include revisions of estimated profits on contracts in earnings under the cumulative catch-up method, under which the effect of revisions in estimates is recognized immediately. If a revised estimate of contract profitability reveals an anticipated loss on the contract, we recognize the loss in the period it is identified. The percentage of completion method of accounting involves the use of various estimating techniques to project costs at completion, and in some cases includes estimates of recoveries asserted against the customer for changes in specifications or other disputes. Contract estimates involve various assumptions and projections relative to the outcome of future events over multiple periods, including future labor productivity and availability, the nature and complexity of the work to be performed, the cost and availability of materials, the effect of delayed performance, and the availability and timing of funding from the customer. These estimates are based on our best judgment. A significant change in one or more of these estimates could affect the profitability of one or more of our contracts. We review our contract estimates regularly to assess revisions in contract values and estimated costs at completion. Inherent uncertainties in estimating costs make it at least reasonably possible that the estimates used will change within the near term and over the life of the contracts. No material adjustments to a contract were recognized in the three and six months ended June 29, 2019 . Costs and estimated earnings in excess of billings are composed principally of revenue recognized on contracts on the percentage of completion method for which billings had not been presented to customers because the amounts were not billable under the contract terms at the balance sheet date. In accordance with the contract terms, the unbilled receivables at the balance sheet date are expected to be billed in following periods. Billings in excess of costs and estimated earnings represent billings in excess of revenue recognized. Contract assets and liabilities are netted on a contract-by-contract basis. Earnings per Share— The Company computes basic earnings per share attributable to stockholders by dividing income attributable to Summit Inc. by the weighted-average shares of Class A common stock outstanding. Diluted earnings per share reflects the potential dilution beyond shares for basic earnings per share that could occur if securities or other contracts to issue common stock were exercised, converted into common stock, or resulted in the issuance of common stock that would have shared in the Company’s earnings. Since the Class B common stock has no economic value, those shares are not included in the weighted-average common share amount for basic or diluted earnings per share. In addition, as the shares of Class A common stock are issued by Summit Inc., the earnings and equity interests of noncontrolling interests are not included in basic earnings per share. Tax Receivable Agreement — When Class A limited partnership units of Summit Holdings (“LP Units”) are exchanged for shares of Class A common stock of Summit Inc. or Summit Inc. purchases LP Units for cash, this results in increases in Summit Inc.’s share of the tax basis of the tangible and intangible assets, which increases the tax depreciation and amortization deductions that otherwise would not have been available to Summit Inc. These increases in tax basis and tax depreciation and amortization deductions are expected to reduce the amount of cash taxes that we would otherwise be required to pay in the future. Prior to our initial public offering (“IPO”), we entered into a TRA with the pre-IPO owners that requires us to pay the pre-IPO owners or their permitted assignees 85% of the amount of cash savings, if any, in U.S. federal, state, and local income tax that we actually realize as a result of these exchanges. These benefits include (1) increases in the tax basis of tangible and intangible assets of Summit Holdings and certain other tax benefits related to entering into the TRA, (2) tax benefits attributable to payments under the TRA, or (3) under certain circumstances such as an early termination of the TRA, we are deemed to realize, as a result of the increases in tax basis in connection with exchanges by the pre-IPO owners described above and certain other tax benefits attributable to payments under the TRA. We periodically evaluate the realizability of the deferred tax assets resulting from the exchange of LP Units for Class A common stock. If the deferred tax assets are determined to be realizable, we then assess whether payment of amounts under the TRA have become probable. If so, we record a TRA liability equal to 85% of such deferred tax assets, and the remaining 15% as an increase to additional paid-in capital. If a deferred tax asset subject to the TRA is determined not to be realizable and therefore subject to a valuation allowance, we do not record a TRA liability for such deferred tax assets. In subsequent periods, we assess the realizability of all of our deferred tax assets subject to the TRA. Should we determine a deferred tax asset with a valuation allowance is realizable in a subsequent period, the related valuation allowance will be released and consideration of a corresponding TRA liability will be assessed. The realizability of deferred tax assets, including those subject to the TRA, is dependent upon the generation of future taxable income during the periods in which those deferred tax assets become deductible and consideration of prudent and feasible tax-planning strategies. The measurement of the TRA liability is accounted for as a contingent liability. Therefore, once we determine that a payment to a pre-IPO owner has become probable and can be estimated, the estimate of payment will be accrued. New Accounting Standards — In February 2016, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) No. 2016-02, Leases (Topic 842), which requires lessees to recognize most leases on the balance sheet. Lessees are required to disclose more quantitative and qualitative information about the leases than current U.S. GAAP requires. The ASU and subsequent amendments issued in 2018 are effective for public entities for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2018. We adopted the standard effective December 30, 2018 using the modified retrospective approach. The modified retrospective approach provides a method for recording existing leases at adoption. In addition, we elected the package of practical expedients permitted under the transition guidance within the new standard, which among other things, allowed us to carry forward the historical lease classification. In addition, we elected the hindsight practical expedient to determine the lease term for existing leases. The most significant impact upon adoption was the recognition of $36.8 million of operating lease right-of-use assets and $36.8 million operating lease liabilities. The standard had no material impact on our statement of cash flows. In August 2017, the FASB issued ASU No. 2017-12, Derivatives and Hedging (Topic 815): Targeted Improvements to Accounting for Hedging Activities, allowing more financial and nonfinancial hedging strategies to be eligible for hedge accounting. The ASU is effective for fiscal years beginning after December 15, 2018 and interim periods within those fiscal years. The adoption of this new ASU did not have a material impact on our consolidated financial results. In June 2018, the FASB issued ASU No. 2018-07, Compensation—Stock Compensation (Topic 718): Improvements to Nonemployee Share-Based Payment Accounting, increasing the scope of Topic 718 to include share-based payment transactions for acquiring goods and services from nonemployees. The ASU is effective for fiscal years beginning after December 15, 2018 and interim periods within those fiscal years. The adoption of this new ASU did not have a material impact on our consolidated financial results.
Summit Materials, LLC
Summary Of Significant Accounting Policies And Recent Accounting Pronouncements [Line Items]
Summary of Organization and Significant Accounting Policies	SUMMARY OF ORGANIZATION AND SIGNIFICANT ACCOUNTING POLICIES Summit Materials, LLC (“Summit LLC” and, together with its subsidiaries, “Summit,” “we,” “us,” “our” or the “Company”) is a vertically-integrated construction materials company. The Company is engaged in the production and sale of aggregates, cement, ready-mix concrete, asphalt paving mix and concrete products and owns and operates quarries, sand and gravel pits, two cement plants, cement distribution terminals, ready-mix concrete plants, asphalt plants and landfill sites. It is also engaged in paving and related services. The Company’s three operating and reporting segments are the West, East and Cement segments. Substantially all of the Company’s construction materials, products and services are produced, consumed and performed outdoors, primarily in the spring, summer and fall. Seasonal changes and other weather-related conditions can affect the production and sales volumes of its products and delivery of services. Therefore, the financial results for any interim period are typically not indicative of the results expected for the full year. Furthermore, the Company’s sales and earnings are sensitive to national, regional and local economic conditions, weather conditions and to cyclical changes in construction spending, among other factors. Summit LLC is a wholly owned indirect subsidiary of Summit Materials Holdings L.P. (“Summit Holdings”), whose primary owner is Summit Materials, Inc. (“Summit Inc.”). Summit Inc. was formed as a Delaware corporation on September 23, 2014. Its sole material asset is a controlling equity interest in Summit Holdings. Pursuant to a reorganization into a holding company structure (the “Reorganization”) consummated in connection with Summit Inc.’s March 2015 initial public offering, Summit Inc. became a holding corporation operating and controlling all of the business and affairs of Summit Holdings and its subsidiaries, including Summit LLC. Basis of Presentation —These unaudited consolidated financial statements were prepared in accordance with U.S. generally accepted accounting principles (“U.S. GAAP”) for interim financial information, without audit, pursuant to the rules and regulations of the Securities and Exchange Commission (“SEC”). Certain information and footnote disclosures typically included in financial statements prepared in accordance with U.S. GAAP have been condensed or omitted pursuant to such rules and regulations. These unaudited consolidated financial statements should be read in conjunction with the Company’s audited consolidated financial statements and the notes thereto as of and for the year ended December 29, 2018 . The Company continues to follow the accounting policies set forth in those audited consolidated financial statements. Management believes that these consolidated interim financial statements include all adjustments, normal and recurring in nature, that are necessary to present fairly the financial position of the Company as of June 29, 2019 , the results of operations for the three and six months ended June 29, 2019 and June 30, 2018 and cash flows for the six months ended June 29, 2019 and June 30, 2018 . Use of Estimates —Preparation of these consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions. These estimates and the underlying assumptions affect the amounts of assets and liabilities reported, disclosures about contingent assets and liabilities and reported amounts of revenue and expenses. Such estimates include the valuation of accounts receivable, inventories, valuation of deferred tax assets, goodwill, intangibles and other long-lived assets, pension and other postretirement obligations and asset retirement obligations. Estimates also include revenue earned on contracts and costs to complete contracts. Most of the Company’s paving and related services are performed under fixed unit-price contracts with state and local governmental entities. Management regularly evaluates its estimates and assumptions based on historical experience and other factors, including the current economic environment. As future events and their effects cannot be determined with precision, actual results can differ significantly from estimates made. Changes in estimates, including those resulting from continuing changes in the economic environment, are reflected in the Company’s consolidated financial statements when the change in estimate occurs. Business and Credit Concentrations— The Company’s operations are conducted primarily across 23 U.S. states and in British Columbia, Canada, with the most significant revenue generated in Texas, Utah, Kansas and Missouri. The Company’s accounts receivable consist primarily of amounts due from customers within these areas. Therefore, collection of these accounts is dependent on the economic conditions in the aforementioned states, as well as specific situations affecting individual customers. Credit granted within the Company’s trade areas has been granted to many customers, and management does not believe that a significant concentration of credit exists with respect to any individual customer or group of customers. No single customer accounted for more than 10% of the Company’s total revenue in the three and six months ended June 29, 2019 or June 30, 2018 . Revenue Recognition —We earn revenue from the sale of products, which primarily include aggregates, cement, ready-mix concrete and asphalt, but also include concrete products and plastics components, and from the provision of services, which are primarily paving and related services, but also include landfill operations, the receipt and disposal of waste that is converted to fuel for use in our cement plants and underground storage space rental. Products We earn revenue from the sale of products, which primarily include aggregates, cement, ready-mix concrete and asphalt, but also include concrete products, net of discounts or allowances, if any, and freight and delivery charges billed to customers. Freight and delivery charges associated with cement sales are recorded on a net basis together with freight costs within cost of sales. Revenue for product sales is recognized when evidence of an arrangement exists and when control passes, which generally is when the product is shipped. Services We earn revenue from the provision of services, which are primarily paving and related services, but also include landfill operations, the receipt and disposal of waste that is converted to fuel for use in our cement plants, and underground storage space rental. Revenue from the receipt of waste fuels is recognized when the waste is accepted and a corresponding liability is recognized for the costs to process the waste into fuel for the manufacturing of cement or to ship the waste offsite for disposal in accordance with applicable regulations. Revenue derived from paving and related services is recognized using the percentage of completion method, which approximates progress towards completion. Under the percentage of completion method, we recognize paving and related services revenue as services are rendered. The majority of our construction service contracts are completed within one year, but may occasionally extend beyond this time frame. We estimate profit as the difference between total estimated revenue and total estimated cost of a contract and recognize that profit over the life of the contract based on input measures. We generally measure progress toward completion on long-term paving and related services contracts based on the proportion of costs incurred to date relative to total estimated costs at completion. We include revisions of estimated profits on contracts in earnings under the cumulative catch-up method, under which the effect of revisions in estimates is recognized immediately. If a revised estimate of contract profitability reveals an anticipated loss on the contract, we recognize the loss in the period it is identified. The percentage of completion method of accounting involves the use of various estimating techniques to project costs at completion, and in some cases includes estimates of recoveries asserted against the customer for changes in specifications or other disputes. Contract estimates involve various assumptions and projections relative to the outcome of future events over multiple periods, including future labor productivity and availability, the nature and complexity of the work to be performed, the cost and availability of materials, the effect of delayed performance, and the availability and timing of funding from the customer. These estimates are based on our best judgment. A significant change in one or more of these estimates could affect the profitability of one or more of our contracts. We review our contract estimates regularly to assess revisions in contract values and estimated costs at completion. Inherent uncertainties in estimating costs make it at least reasonably possible that the estimates used will change within the near term and over the life of the contracts. No material adjustments to a contract were recognized in the three and six months ended June 29, 2019 . Costs and estimated earnings in excess of billings are composed principally of revenue recognized on contracts on the percentage of completion method for which billings had not been presented to customers because the amounts were not billable under the contract terms at the balance sheet date. In accordance with the contract terms, the unbilled receivables at the balance sheet date are expected to be billed in following periods. Billings in excess of costs and estimated earnings represent billings in excess of revenue recognized. Contract assets and liabilities are netted on a contract-by-contract basis. New Accounting Standards — In February 2016, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) No. 2016-02, Leases (Topic 842), which requires lessees to recognize most leases on the balance sheet. Lessees are required to disclose more quantitative and qualitative information about the leases than current U.S. GAAP requires. The ASU and subsequent amendments issued in 2018 are effective for public entities for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2018. We adopted the standard effective December 30, 2018 using the modified retrospective approach. The modified retrospective approach provides a method for recording existing leases at adoption. In addition, we elected the package of practical expedients permitted under the transition guidance within the new standard, which among other things, allowed us to carry forward the historical lease classification. In addition, we elected the hindsight practical expedient to determine the lease term for existing leases. The most significant impact upon adoption was the recognition of $36.8 million of operating lease right-of-use assets and $36.8 million operating lease liabilities. The standard had no material impact on our statement of cash flows. In August 2017, the FASB issued ASU No. 2017-12, Derivatives and Hedging (Topic 815): Targeted Improvements to Accounting for Hedging Activities, allowing more financial and nonfinancial hedging strategies to be eligible for hedge accounting. The ASU is effective for fiscal years beginning after December 15, 2018 and interim periods within those fiscal years. The adoption of this new ASU did not have a material impact on our consolidated financial results. In June 2018, the FASB issued ASU No. 2018-07, Compensation-Stock Compensation (Topic 718): Improvements to Nonemployee Share-Based Payment Accounting, increasing the scope of Topic 718 to include share-based payment transactions for acquiring goods and services from nonemployees. The ASU is effective for fiscal years beginning after December 15, 2018 and interim periods within those fiscal years. The adoption of this new ASU did not have a material impact on our consolidated financial results.

GOODWILL AND INTANGIBLES

GOODWILL AND INTANGIBLES	6 Months Ended
	Jun. 29, 2019
Business Acquisition [Line Items]
Goodwill and Intangibles	GOODWILL AND INTANGIBLES The Company has completed numerous acquisitions since its formation, which have been financed through a combination of debt and equity funding. The operations of each acquisition have been included in the Company’s consolidated results of operations since the respective closing dates of the acquisitions. The Company measures all assets acquired and liabilities assumed at their acquisition-date fair value. Changes in the carrying amount of goodwill, by reportable segment, from December 29, 2018 to June 29, 2019 are summarized as follows: West East Cement Total Balance, December 29, 2018 $ 580,567 $ 406,805 $ 204,656 $ 1,192,028 Acquisitions (1) 1,173 2,621 — 3,794 Foreign currency translation adjustments 2,355 — — 2,355 Balance, June 29, 2019 $ 584,095 $ 409,426 $ 204,656 $ 1,198,177 _____________________________________________________________________________________________ (1) Reflects goodwill from 2019 acquisitions and working capital adjustments from prior year acquisitions. The Company’s intangible assets are primarily composed of goodwill, mineral lease agreements and reserve rights. The assets related to mineral lease agreements reflect the submarket royalty rates paid under agreements, primarily for extracting aggregates. The values were determined as of the respective acquisition dates by a comparison of market-royalty rates. The reserve rights relate to aggregate reserves to which the Company has the rights of ownership, but does not own the reserves. The intangible assets are amortized on a straight-line basis over the lives of the leases. The following table shows intangible assets by type and in total: June 29, 2019 December 29, 2018 Gross Carrying Amount Accumulated Amortization Net Carrying Amount Gross Carrying Amount Accumulated Amortization Net Carrying Amount Mineral leases $ 19,064 $ (5,835 ) $ 13,229 $ 19,064 $ (5,259 ) $ 13,805 Reserve rights 6,234 (2,098 ) 4,136 6,234 (1,940 ) 4,294 Trade names 1,000 (908 ) 92 1,000 (858 ) 142 Other 409 (213 ) 196 409 (190 ) 219 Total intangible assets $ 26,707 $ (9,054 ) $ 17,653 $ 26,707 $ (8,247 ) $ 18,460 Amortization expense totaled $0.4 million and $0.8 million for the three and six months ended June 29, 2019, respectively, and $0.3 million and $0.6 million for the three and six months June 30, 2018 , respectively. The estimated amortization expense for the intangible assets for each of the five years subsequent to June 29, 2019 is as follows: 2019 (six months) $ 791 2020 1,510 2021 1,475 2022 1,482 2023 1,349 2024 1,254 Thereafter 9,792 Total $ 17,653
Summit Materials, LLC
Business Acquisition [Line Items]
Goodwill and Intangibles	GOODWILL AND INTANGIBLES The Company has completed numerous acquisitions since its formation, which have been financed through a combination of debt and equity funding. The operations of each acquisition have been included in the Company’s consolidated results of operations since the respective closing dates of the acquisitions. The Company measures all assets acquired and liabilities assumed at their acquisition-date fair value. Changes in the carrying amount of goodwill, by reportable segment, from December 29, 2018 to June 29, 2019 are summarized as follows: West East Cement Total Balance, December 29, 2018 $ 581,567 $ 406,805 $ 204,656 $ 1,193,028 Acquisitions (1) 1,173 2,621 — 3,794 Foreign currency translation adjustments 2,355 — — 2,355 Balance, June 29, 2019 $ 585,095 $ 409,426 $ 204,656 $ 1,199,177 _______________________________________________________________________ (1) Reflects goodwill from 2019 acquisitions and working capital adjustments from prior year acquisitions. The Company’s intangible assets are primarily composed of goodwill, mineral lease agreements and reserve rights. The assets related to mineral lease agreements reflect the submarket royalty rates paid under agreements, primarily for extracting aggregates. The values were determined as of the respective acquisition dates by a comparison of market-royalty rates. The reserve rights relate to aggregate reserves to which the Company has the rights of ownership, but does not own the reserves. The intangible assets are amortized on a straight-line basis over the lives of the leases. The following table shows intangible assets by type and in total: June 29, 2019 December 29, 2018 Gross Carrying Amount Accumulated Amortization Net Carrying Amount Gross Carrying Amount Accumulated Amortization Net Carrying Amount Mineral leases $ 19,064 $ (5,835 ) $ 13,229 $ 19,064 $ (5,259 ) $ 13,805 Reserve rights 6,234 (2,098 ) 4,136 6,234 (1,940 ) 4,294 Trade names 1,000 (908 ) 92 1,000 (858 ) 142 Other 409 (213 ) 196 409 (190 ) 219 Total intangible assets $ 26,707 $ (9,054 ) $ 17,653 $ 26,707 $ (8,247 ) $ 18,460 Amortization expense totaled $0.4 million and $0.8 million for the three and six months ended June 29, 2019 , respectively, and $0.3 million and $0.6 million for the three and six months June 30, 2018 , respectively. The estimated amortization expense for the intangible assets for each of the five years subsequent to June 29, 2019 is as follows: 2019 (six months) $ 791 2020 1,510 2021 1,475 2022 1,482 2023 1,349 2024 1,254 Thereafter 9,792 Total $ 17,653

REVENUE RECOGNITION

REVENUE RECOGNITION	6 Months Ended
	Jun. 29, 2019
Revenue from External Customer [Line Items]
Revenue Recognition	REVENUE RECOGNITION We derive our revenue predominantly by selling construction materials, products and providing paving and related services. Construction materials consist of aggregates and cement. Products consist of related downstream products, including ready-mix concrete, asphalt paving mix and concrete products. Paving and related service revenue is generated primarily from the asphalt paving services that we provide. Revenue by product for the three and six months ended June 29, 2019 and June 30, 2018 is as follows: Three months ended Six months ended June 29, 2019 June 30, 2018 June 29, 2019 June 30, 2018 Revenue by product*: Aggregates $ 128,650 $ 103,690 $ 216,522 $ 171,140 Cement 77,799 76,413 110,298 109,530 Ready-mix concrete 154,180 160,609 271,500 282,624 Asphalt 93,365 88,372 116,403 106,513 Paving and related services 95,304 107,306 129,649 141,642 Other 51,593 64,500 89,158 103,862 Total revenue $ 600,891 $ 600,890 $ 933,530 $ 915,311 *Revenue from liquid asphalt terminals is included in asphalt revenue. The following table outlines the significant changes in contract assets and contract liability balances from December 29, 2018 to June 29, 2019 . Also included in the table is the net change in estimate as a percentage of aggregate revenue for such contracts: Costs and estimated earnings in excess of billings Billings in excess of costs and estimated earnings Balance - December 29, 2018 $ 18,602 $ 11,840 Changes in revenue billed, contract price or cost estimates 26,715 (1,138 ) Other 54 31 Balance - June 29, 2019 $ 45,371 $ 10,733 Accounts receivable, net consisted of the following as of June 29, 2019 and December 29, 2018 : June 29, 2019 December 29, 2018 Trade accounts receivable $ 232,597 $ 157,601 Construction contract receivables 52,536 47,994 Retention receivables 14,573 15,010 Receivables from related parties 1,198 629 Accounts receivable 300,904 221,234 Less: Allowance for doubtful accounts (6,300 ) (6,716 ) Accounts receivable, net $ 294,604 $ 214,518 Retention receivables are amounts earned by the Company but held by customers until paving and related service contracts and projects are near completion or fully completed. Amounts are generally billed and collected within one year .
Summit Materials, LLC
Revenue from External Customer [Line Items]
Revenue Recognition	REVENUE RECOGNITION We derive our revenue predominantly by selling construction materials, products and providing paving and related services. Construction materials consist of aggregates and cement. Products consist of related downstream products, including ready-mix concrete, asphalt paving mix and concrete products. Paving and related service revenue is generated primarily from the asphalt paving services that we provide. Revenue by product for the three and six months ended June 29, 2019 and June 30, 2018 is as follows: Three months ended Six months ended June 29, June 30, June 29, June 30, 2019 2018 2019 2018 Revenue by product*: Aggregates $ 128,650 $ 103,690 $ 216,522 $ 171,140 Cement 77,799 76,413 110,298 109,530 Ready-mix concrete 154,180 160,609 271,500 282,624 Asphalt 93,365 88,372 116,403 106,513 Paving and related services 95,304 107,306 129,649 141,642 Other 51,593 64,500 89,158 103,862 Total revenue $ 600,891 $ 600,890 $ 933,530 $ 915,311 *Revenue from liquid asphalt terminals is included in asphalt revenue. The following table outlines the significant changes in contract assets and contract liability balances from December 29, 2018 to June 29, 2019 . Also included in the table is the net change in estimate as a percentage of aggregate revenue for such contracts: Costs and estimated Billings in excess earnings in of costs and excess of billings estimated earnings Balance - December 29, 2018 $ 18,602 $ 11,840 Changes in revenue billed, contract price or cost estimates 26,715 (1,138 ) Other 54 31 Balance - June 29, 2019 $ 45,371 $ 10,733 Accounts receivable, net consisted of the following as of June 29, 2019 and December 29, 2018 : June 29, December 29, 2019 2018 Trade accounts receivable $ 232,597 $ 157,601 Construction contract receivables 52,536 47,994 Retention receivables 14,573 15,010 Receivables from related parties 1,198 629 Accounts receivable 300,904 221,234 Less: Allowance for doubtful accounts (6,300 ) (6,716 ) Accounts receivable, net $ 294,604 $ 214,518 Retention receivables are amounts earned by the Company but held by customers until paving and related service contracts and projects are near completion or fully completed. Amounts are generally billed and collected within one year .

INVENTORIES

INVENTORIES	6 Months Ended
	Jun. 29, 2019
Inventory [Line Items]
Inventories	INVENTORIES Inventories consisted of the following as of June 29, 2019 and December 29, 2018 : June 29, 2019 December 29, 2018 Aggregate stockpiles $ 146,264 $ 151,300 Finished goods 29,272 34,993 Work in process 7,754 7,478 Raw materials 24,846 20,080 Total $ 208,136 $ 213,851
Summit Materials, LLC
Inventory [Line Items]
Inventories	INVENTORIES Inventories consisted of the following as of June 29, 2019 and December 29, 2018 : June 29, 2019 December 29, 2018 Aggregate stockpiles $ 146,264 $ 151,300 Finished goods 29,272 34,993 Work in process 7,754 7,478 Raw materials 24,846 20,080 Total $ 208,136 $ 213,851

ACCRUED EXPENSES

ACCRUED EXPENSES	6 Months Ended
	Jun. 29, 2019
Schedule Of Accrued Expenses [Line Items]
Accrued Expenses	ACCRUED EXPENSES Accrued expenses consisted of the following as of June 29, 2019 and December 29, 2018 : June 29, 2019 December 29, 2018 Interest $ 25,326 $ 26,223 Payroll and benefits 22,482 15,952 Finance lease obligations 17,805 15,557 Insurance 15,807 13,625 Non-income taxes 13,075 7,442 Professional fees 1,482 1,408 Other (1) 18,019 20,284 Total $ 113,996 $ 100,491 (1) Consists primarily of subcontractor and working capital settlement accruals.
Summit Materials, LLC
Schedule Of Accrued Expenses [Line Items]
Accrued Expenses	ACCRUED EXPENSES Accrued expenses consisted of the following as of June 29, 2019 and December 29, 2018 : June 29, 2019 December 29, 2018 Interest $ 25,326 $ 26,223 Payroll and benefits 22,482 15,952 Finance lease obligations 17,805 15,557 Insurance 15,807 13,625 Non-income taxes 13,307 7,674 Professional fees 1,482 1,408 Other (1) 18,019 19,590 Total $ 114,228 $ 100,029 _______________________________________________________________________ (1) Consists primarily of subcontractor and working capital settlement accruals.

DEBT

DEBT	6 Months Ended
	Jun. 29, 2019
Debt Instrument [Line Items]
Debt	DEBT Debt consisted of the following as of June 29, 2019 and December 29, 2018 : June 29, 2019 December 29, 2018 Term Loan, due 2024: $625.8 million and $630.6 million, net of $1.2 million and $1.3 million discount at June 29, 2019 and December 29, 2018, respectively $ 624,615 $ 629,268 8 1 ⁄ 2 % Senior Notes, due 2022 — 250,000 6 1 ⁄ 8 % Senior Notes, due 2023: $650.0 million, net of $1.0 million and $1.1 million discount at June 29, 2019 and December 29, 2018, respectively 649,012 648,891 5 1 ⁄ 8 % Senior Notes, due 2025 300,000 300,000 6 1 ⁄ 2 % Senior Notes, due 2027 300,000 — Total 1,873,627 1,828,159 Current portion of long-term debt 4,765 6,354 Long-term debt $ 1,868,862 $ 1,821,805 The contractual payments of long-term debt, including current maturities, for the five years subsequent to June 29, 2019 , are as follows: 2019 (six months) $ 1,588 2020 7,942 2021 6,354 2022 6,354 2023 656,354 2024 597,252 Thereafter 600,000 Total 1,875,844 Less: Original issue net discount (2,217 ) Less: Capitalized loan costs (14,673 ) Total debt $ 1,858,954 Senior Notes —On March 15, 2019, Summit LLC and Summit Finance (together, the “Issuers”) issued $300.0 million in aggregate principal amount of 6.500% senior notes due March 15, 2027 (the “2027 Notes”). The 2027 Notes were issued at 100.0% of their par value with proceeds of $296.3 million , net of related fees and expenses. The 2027 Notes were issued under an indenture dated March 25, 2019 (the "2019 Indenture"). The 2019 Indenture contains covenants limiting, among other things, Summit LLC and its restricted subsidiaries’ ability to incur additional indebtedness or issue certain preferred shares, pay dividends, redeem stock or make other distributions, make certain investments, sell or transfer certain assets, create liens, consolidate, merge, sell or otherwise dispose of all or substantially all of its assets, enter into certain transactions with affiliates, and designate subsidiaries as unrestricted subsidiaries. The 2019 Indenture also contains customary events of default. Interest on the 2027 Notes is payable semi-annually on March 15 and September 15 of each year commencing on September 15, 2019. In March 2019, using the proceeds from the 2027 Notes, all of the outstanding $250.0 million 8.500% senior notes due 2022 (the “2022 Notes”) were redeemed at a price equal to par plus an applicable premium and the indenture under which the 2022 Notes were issued was satisfied and discharged. As a result of the extinguishment, charges of $14.6 million were recognized in the quarter ended March 30, 2019, which included charges of $11.7 million for the applicable redemption premium and $2.9 million for the write-off of deferred financing fees. In 2017, the Issuers issued $300.0 million of 5.125% senior notes due June 1, 2025 (the “2025 Notes”). The 2025 Notes were issued at 100.0% of their par value with proceeds of $295.4 million , net of related fees and expenses. The 2025 Notes were issued under an indenture dated June 1, 2017, the terms of which are generally consistent with the 2019 Indenture. Interest on the 2025 Notes is payable semi-annually on June 1 and December 1 of each year commencing on December 1, 2017. In 2015, the Issuers issued $650.0 million of 6.125% senior notes due July 2023 (the “2023 Notes” and collectively with the 2025 Notes and the 2027 Notes, the “Senior Notes”). Of the aggregate $650.0 million of 2023 Notes, $350.0 million were issued at par and $300.0 million were issued at 99.375% of par. The 2023 Notes were issued under an indenture dated July 8, 2015, the terms of which are generally consistent with the 2019 Indenture. Interest on the 2023 Notes is payable semi-annually in arrears on January 15 and July 15 of each year. As of June 29, 2019 and December 29, 2018 , the Company was in compliance with all financial covenants under the applicable indentures. Senior Secured Credit Facilities — Summit LLC has credit facilities that provide for term loans in an aggregate amount of $650.0 million and revolving credit commitments in an aggregate amount of $345.0 million (the “Senior Secured Credit Facilities”). Under the Senior Secured Credit Facilities, required principal repayments of 0.25% of the refinanced aggregate amount of term debt are due on the last business day of each March, June, September and December commencing with the March 2018 payment. The unpaid principal balance is due in full on the maturity date, which is November 21, 2024. On February 25, 2019, Summit LLC entered into Incremental Amendment No. 4 to the credit agreement governing the Senior Secured Credit Facilities (the “Credit Agreement”) which, among other things, increased the total amount available under the revolving credit facility to $345.0 million and extended the maturity date of the Credit Agreement to February 2024. During 2018 and 2017, Summit LLC entered into three different amendments to the Credit Agreement, which among other things, reduced the applicable margin in respect to the outstanding principal amount at the time of the respective amendments. The revolving credit facility bears interest per annum equal to, at Summit LLC’s option, either (i) a base rate determined by reference to the highest of (a) the federal funds rate plus 0.50% , (b) the prime rate of Bank of America, N.A. and (c) LIBOR plus 1.00% , plus an applicable margin of 2.00% for base rate loans or (ii) a LIBOR rate determined by reference to Reuters prior to the interest period relevant to such borrowing adjusted for certain additional costs plus an applicable margin of 3.00% for LIBOR rate loans. There were no outstanding borrowings under the revolving credit facility as of June 29, 2019 and December 29, 2018 , leaving remaining borrowing capacity of $329.8 million as of June 29, 2019 , which is net of $15.2 million of outstanding letters of credit. The outstanding letters of credit are renewed annually and support required bonding on construction projects, large leases, workers compensation claims and the Company’s insurance liabilities. Summit LLC’s Consolidated First Lien Net Leverage Ratio, as such term is defined in the Credit Agreement, should be no greater than 4.75 : 1.0 as of each quarter-end. As of June 29, 2019 and December 29, 2018 , Summit LLC was in compliance with all financial covenants. Summit LLC’s wholly-owned domestic subsidiary companies, subject to certain exclusions and exceptions, are named as subsidiary guarantors of the Senior Notes and the Senior Secured Credit Facilities. In addition, Summit LLC has pledged substantially all of its assets as collateral, subject to certain exclusions and exceptions, for the Senior Secured Credit Facilities. The following table presents the activity for the deferred financing fees for the six months ended June 29, 2019 and June 30, 2018 : Deferred financing fees Balance—December 29, 2018 $ 15,475 Loan origination fees 6,246 Amortization (1,832 ) Write off of deferred financing fees (2,851 ) Balance—June 29, 2019 $ 17,038 Balance - December 30, 2017 $ 19,033 Loan origination fees 550 Amortization (2,040 ) Balance - June 30, 2018 $ 17,543 Other —On January 15, 2015, the Company’s wholly-owned subsidiary in British Columbia, Canada entered into an agreement with HSBC for a (i) $6.0 million Canadian dollar (“CAD”) revolving credit commitment to be used for operating activities that bears interest per annum equal to the bank’s prime rate plus 0.20% , (ii) $0.5 million CAD revolving credit commitment to be used for capital equipment that bears interest per annum at the bank’s prime rate plus 0.90% and (iii) $0.4 million CAD revolving credit commitment to provide guarantees on behalf of that subsidiary. There were no amounts outstanding under this agreement as of June 29, 2019 or December 29, 2018 .
Summit Materials, LLC
Debt Instrument [Line Items]
Debt	DEBT Debt consisted of the following as of June 29, 2019 and December 29, 2018 : June 29, 2019 December 29, 2018 Term Loan, due 2024: $625.8 million and $630.6 million, net of $1.2 million and $1.3 million discount at June 29, 2019 and December 29, 2018, respectively $ 624,615 $ 629,268 8 1/2 % Senior Notes, due 2022 — 250,000 6 1/8 % Senior Notes, due 2023: $650.0 million, net of $1.0 million and $1.1 million discount at June 29, 2019 and December 29, 2018, respectively 649,012 648,891 5 1⁄8 % Senior Notes, due 2025 300,000 300,000 6 1⁄2 % Senior Notes, due 2027 300,000 — Total 1,873,627 1,828,159 Current portion of long-term debt 4,765 6,354 Long-term debt $ 1,868,862 $ 1,821,805 The contractual payments of long-term debt, including current maturities, for the five years subsequent to June 29, 2019 , are as follows: 2019 (six months) $ 1,588 2020 7,942 2021 6,354 2022 6,354 2023 656,354 2024 597,252 Thereafter 600,000 Total 1,875,844 Less: Original issue net discount (2,217 ) Less: Capitalized loan costs (14,673 ) Total debt $ 1,858,954 Senior Notes —On March 15, 2019, Summit LLC and Summit Materials Finance Corp., an indirect wholly-owned subsidiary of Summit LLC (“Finance Corp.” and together with Summit LLC, the “Issuers”) issued $300.0 million in aggregate principal amount of 6.500% senior notes due March 15, 2027 (the “2027 Notes”). The 2027 Notes were issued at 100.0% of their par value with proceeds of $296.3 million , net of related fees and expenses. The 2027 Notes were issued under an indenture dated March 25, 2019 (the "2019 Indenture"). The 2019 Indenture contains covenants limiting, among other things, Summit LLC and its restricted subsidiaries’ ability to incur additional indebtedness or issue certain preferred shares, pay dividends, redeem stock or make other distributions, make certain investments, sell or transfer certain assets, create liens, consolidate, merge, sell or otherwise dispose of all or substantially all of its assets, enter into certain transactions with affiliates, and designate subsidiaries as unrestricted subsidiaries. The 2019 Indenture also contains customary events of default. Interest on the 2027 Notes is payable semi-annually on March 15 and September 15 of each year commencing on September 15, 2019. In March 2019, using the proceeds from the 2027 Notes, all of the outstanding $250.0 million 8.500% senior notes due 2022 (the “2022 Notes”) were redeemed at a price equal to par plus an applicable premium and the indenture under which the 2022 Notes were issued was satisfied and discharged. As a result of the extinguishment, charges of $14.6 million were recognized in the quarter ended March 30, 2019, which included charges of $11.7 million for the applicable redemption premium and $2.9 million for the write-off of deferred financing fees. In 2017, the Issuers issued $300.0 million of 5.125% senior notes due June 1, 2025 (the “2025 Notes”). The 2025 Notes were issued at 100.0% of their par value with proceeds of $295.4 million , net of related fees and expenses. The 2025 Notes were issued under an indenture dated June 1, 2017, the terms of which are generally consistent with the 2019 Indenture. Interest on the 2025 Notes is payable semi-annually on June 1 and December 1 of each year commencing on December 1, 2017. In 2015, the Issuers issued $650.0 million of 6.125% senior notes due July 2023 (the “2023 Notes” and collectively with the 2025 Notes and the 2027 Notes, the “Senior Notes”). Of the aggregate $650.0 million of 2023 Notes, $350.0 million were issued at par and $300.0 million were issued at 99.375% of par. The 2023 Notes were issued under an indenture dated July 8, 2015, the terms of which are generally consistent with the 2019 Indenture. Interest on the 2023 Notes is payable semi-annually in arrears on January 15 and July 15 of each year. As of June 29, 2019 and December 29, 2018 , the Company was in compliance with all financial covenants under the applicable indentures. Senior Secured Credit Facilities — Summit LLC has credit facilities that provide for term loans in an aggregate amount of $650.0 million and revolving credit commitments in an aggregate amount of $345.0 million (the “Senior Secured Credit Facilities”). Under the Senior Secured Credit Facilities, required principal repayments of 0.25% of the refinanced aggregate amount of term debt are due on the last business day of each March, June, September and December commencing with the March 2018 payment. The unpaid principal balance is due in full on the maturity date, which is November 21, 2024. On February 25, 2019, Summit LLC entered into Incremental Amendment No. 4 to the credit agreement governing the Senior Secured Credit Facilities (the “Credit Agreement”) which, among other things, increased the total amount available under the revolving credit facility to $345.0 million and extended the maturity date of the Credit Agreement to February 2024. During 2018 and 2017, Summit LLC entered into three different amendments to the Credit Agreement, which among other things, reduced the applicable margin in respect to the outstanding principal amount at the time of the respective amendments. The revolving credit facility bears interest per annum equal to, at Summit LLC’s option, either (i) a base rate determined by reference to the highest of (a) the federal funds rate plus 0.50% , (b) the prime rate of Bank of America, N.A. and (c) LIBOR plus 1.00% , plus an applicable margin of 2.00% for base rate loans or (ii) a LIBOR rate determined by reference to Reuters prior to the interest period relevant to such borrowing adjusted for certain additional costs plus an applicable margin of 3.00% for LIBOR rate loans. There were no outstanding borrowings under the revolving credit facility as of June 29, 2019 and December 29, 2018 , leaving remaining borrowing capacity of $329.8 million as of June 29, 2019 , which is net of $15.2 million of outstanding letters of credit. The outstanding letters of credit are renewed annually and support required bonding on construction projects, large leases, workers compensation claims and the Company’s insurance liabilities. Summit LLC’s Consolidated First Lien Net Leverage Ratio, as such term is defined in the Credit Agreement, should be no greater than 4.75 :1.0 as of each quarter-end. As of June 29, 2019 and December 29, 2018 , Summit LLC was in compliance with all financial covenants. Summit LLC’s wholly-owned domestic subsidiary companies, subject to certain exclusions and exceptions, are named as subsidiary guarantors of the Senior Notes and the Senior Secured Credit Facilities. In addition, Summit LLC has pledged substantially all of its assets as collateral, subject to certain exclusions and exceptions, for the Senior Secured Credit Facilities. The following table presents the activity for the deferred financing fees for the six months ended June 29, 2019 and June 30, 2018 : Deferred financing fees Balance—December 29, 2018 $ 15,475 Loan origination fees 6,246 Amortization (1,832 ) Write off of deferred financing fees (2,851 ) Balance—June 29, 2019 $ 17,038 Balance - December 30, 2017 $ 19,033 Loan origination fees 550 Amortization (2,040 ) Balance - June 30, 2018 $ 17,543 Other —On January 15, 2015, the Company’s wholly-owned subsidiary in British Columbia, Canada entered into an agreement with HSBC for a (i) $6.0 million Canadian dollar (“CAD”) revolving credit commitment to be used for operating activities that bears interest per annum equal to the bank’s prime rate plus 0.20% , (ii) $0.5 million CAD revolving credit commitment to be used for capital equipment that bears interest per annum at the bank’s prime rate plus 0.90% and (iii) $0.4 million CAD revolving credit commitment to provide guarantees on behalf of that subsidiary. There were no amounts outstanding under this agreement as of June 29, 2019 or December 29, 2018 .

INCOME TAXES

INCOME TAXES	6 Months Ended
	Jun. 29, 2019
Income Taxes [Line Items]
Income Taxes	INCOME TAXES Summit Inc.’s tax provision includes its proportional share of Summit Holdings’ tax attributes. Summit Holdings’ subsidiaries are primarily limited liability companies, but do include certain entities organized as C corporations and a Canadian subsidiary. The tax attributes related to the limited liability companies are passed on to Summit Holdings and then to its partners, including Summit Inc. The tax attributes associated with the C corporation and Canadian subsidiaries are fully reflected in the Company’s accounts. Our income tax expense (benefit) was $16.7 million and $(11.3) million and our income tax expense (benefit) was $12.2 million and $(4.5) million in the three and six months ended June 29, 2019 and June 30, 2018 , respectively. The effective tax rate for Summit Inc. differs from the federal rate primarily due to (1) state taxes, (2) tax depletion expense in excess of the expense recorded under U.S. GAAP, (3) the minority interest in the Summit Holdings partnership that is allocated outside of the Company (4) various other items such as limitations on meals and entertainment, certain stock compensation and other costs and (5) unrecognized tax benefits as noted below. As of June 29, 2019 and December 29, 2018 , Summit Inc. had a valuation allowance of $27.9 million and $19.4 million , respectively, which relates to certain deferred tax assets in taxable entities where realization is not more likely than not. Summit Inc. and its subsidiaries expect additional unrecognized tax benefits in 2019 that if recognized would affect the annual effective tax rate, and included that in its estimate of those amounts in its annual effective tax rate. We did not recognize interest or penalties related to this amount as it is offset by other attributes. No material interest or penalties were recognized in income tax expense during the three and six months ended June 29, 2019 and June 30, 2018 . No uncertain tax benefits were recognized in the three and six months ended June 30, 2018 . Tax Receivable Agreement —The Company is party to a TRA with certain current and former holders of LP Units that provides for the payment by Summit Inc. to exchanging holders of LP Units of 85% of the benefits, if any, that Summit Inc. actually realizes (or, under certain circumstances such as an early termination of the TRA, is deemed to realize) as a result of increases in the tax basis of tangible and intangible assets of Summit Holdings and certain other tax benefits related to entering into the TRA, including tax benefits attributable to payments under the TRA. In the six months ended June 29, 2019 , 17,500 LP Units were acquired by Summit Inc. in exchange for an equal number of newly-issued shares of Summit Inc.’s Class A common stock. These exchanges resulted in net new deferred tax assets of approximately $0.1 million . As we determined that the deferred tax assets created from these exchanges are realizable and payment under the TRA is considered probable, we have recorded 85% of the increase in deferred tax assets as TRA liability and the remainder as an increase in additional paid in capital. As of June 29, 2019 and December 29, 2018 , we had recorded $309.7 million and $310.3 million of TRA liability, respectively, of which $0.6 million was classified as accrued expenses as of December 29, 2018 . Tax Distributions – The holders of Summit Holdings’ LP Units, including Summit Inc., incur U.S. federal, state and local income taxes on their share of any taxable income of Summit Holdings. The limited partnership agreement of Summit Holdings provides for pro rata cash distributions (“tax distributions”) to the holders of the LP Units in an amount generally calculated to provide each holder of LP Units with sufficient cash to cover its tax liability in respect of the LP Units. In general, these tax distributions are computed based on Summit Holdings’ estimated taxable income allocated to Summit Inc. multiplied by an assumed tax rate equal to the highest effective marginal combined U.S. federal, state and local income tax rate in New York, New York. Summit Holdings did no t make any tax distributions in the six months ended June 29, 2019 and made $0.1 million in tax distributions in the six months ended June 30, 2018 .
Summit Materials, LLC
Income Taxes [Line Items]
Income Taxes	INCOME TAXES Summit LLC is a limited liability company and passes its tax attributes for federal and state tax purposes to its parent company and is generally not subject to federal or state income tax. However, certain subsidiary entities file federal, state and Canadian income tax returns due to their status as taxable entities in the respective jurisdiction. The effective income tax rate for the C Corporations differs from the statutory federal rate primarily due to (1) tax depletion expense in excess of the expense recorded under U.S. GAAP, (2) state income taxes and the effect of graduated tax rates and (3) various other items, such as limitations on meals and entertainment and other costs. The effective income tax rate for the Canadian subsidiary is not significantly different from its historical effective tax rate. Summit LLC and its subsidiaries expect additional unrecognized tax benefits in 2019 that if recognized would affect the annual effective tax rate, and included that in its estimate of those amounts in its annual effective tax rate. We did not recognize interest or penalties related to this amount as it is offset by other attributes. No material interest or penalties were recognized in income tax expense during the three and six months ended June 29, 2019 and June 30, 2018 . No uncertain tax benefits were recognized in the three and six months ended June 30, 2018 .

EARNINGS PER SHARE

EARNINGS PER SHARE	6 Months Ended
	Jun. 29, 2019
Earnings Per Share [Abstract]
Earnings Per Share	EARNINGS PER SHARE Basic earnings per share is computed by dividing net earnings by the weighted average common shares outstanding and diluted net earnings is computed by dividing net earnings, adjusted for changes in the earnings allocated to Summit Inc. as a result of the assumed conversion of LP Units, by the weighted-average common shares outstanding assuming dilution. The following table shows the calculation of basic and diluted loss per share: Three months ended Six months ended June 29, 2019 June 30, 2018 June 29, 2019 June 30, 2018 Net income (loss) attributable to Summit Inc. $ 36,410 $ 35,509 $ (32,362 ) $ (18,220 ) Weighted average shares of Class A stock outstanding 112,070,009 111,564,190 111,940,844 111,111,644 Basic and diluted income (loss) per share $ 0.32 $ 0.32 $ (0.29 ) $ (0.16 ) Diluted net income (loss) attributable to Summit Inc. $ 36,410 $ 35,509 $ (32,362 ) $ (18,220 ) Weighted average shares of Class A stock outstanding 112,070,009 111,564,190 111,940,844 111,111,644 Add: weighted average of LP Units — — — — Add: stock options — 794,065 — — Add: warrants — 36,488 — — Add: restricted stock units 76,539 91,347 — — Add: performance stock units 36,007 97,231 — — Weighted average dilutive shares outstanding 112,182,555 112,583,321 111,940,844 111,111,644 Diluted earnings (loss) per share $ 0.32 $ 0.32 $ (0.29 ) $ (0.16 ) Excluded from the above calculations were the shares noted below as they were antidilutive: Three months ended Six months ended June 29, 2019 June 30, 2018 June 29, 2019 June 30, 2018 Antidilutive shares: LP Units 3,418,018 3,517,602 3,418,018 3,583,407 Time-vesting stock options 3,168,170 — 3,168,170 3,286,163 Warrants 100,037 — 100,037 100,037 Time-vesting restricted stock units — — 1,493,119 841,618 Market-based restricted stock units — — 390,645 295,252

STOCKHOLDERS' EQUITY_MEMBERS' I

STOCKHOLDERS' EQUITY/MEMBERS' INTEREST	6 Months Ended
	Jun. 29, 2019
Schedule of Capitalization, Equity [Line Items]
Stockholders' Equity	STOCKHOLDERS’ EQUITY During 2019 and 2018, certain limited partners of Summit Holdings exchanged their LP Units for shares of Class A common stock of Summit Inc. The following table summarizes the changes in our ownership of Summit Holdings: Summit Inc. LP Units Total Summit Inc. Balance — December 29, 2018 111,658,927 3,435,518 115,094,445 97.0 % Exchanges during period 17,500 (17,500 ) — Other equity transactions 397,067 — 397,067 Balance — June 29, 2019 112,073,494 3,418,018 115,491,512 97.0 % Balance — December 30, 2017 110,350,594 3,689,620 114,040,214 96.8 % Exchanges during period 229,658 (229,658 ) — Other equity transactions 1,048,986 — 1,048,986 Balance — June 30, 2018 111,629,238 3,459,962 115,089,200 97.0 % As a result of the Reorganization, Summit Inc. is Summit Holdings’ primary beneficiary and thus consolidates Summit Holdings in its consolidated financial statements with a corresponding noncontrolling interest reclassification, which was 3.0% as of June 29, 2019 and December 29, 2018 . Accumulated other comprehensive income (loss) —The changes in each component of accumulated other comprehensive income (loss) consisted of the following: Change in retirement plans Foreign currency translation adjustments Cash flow hedge adjustments Accumulated other comprehensive income (loss) Balance — December 29, 2018 $ 3,573 $ (2,147 ) $ 1,255 $ 2,681 Foreign currency translation adjustment, net of tax — 3,330 — 3,330 Loss on cash flow hedges, net of tax — — (220 ) (220 ) Balance — June 29, 2019 $ 3,573 $ 1,183 $ 1,035 $ 5,791 Balance — December 30, 2017 $ 2,364 $ 4,637 $ 385 $ 7,386 Foreign currency translation adjustment, net of tax — (3,721 ) — (3,721 ) Income on cash flow hedges, net of tax — — 980 980 Balance — June 30, 2018 $ 2,364 $ 916 $ 1,365 $ 4,645
Summit Materials, LLC
Schedule of Capitalization, Equity [Line Items]
Members' Interest	MEMBERS’ INTEREST Accumulated other comprehensive income (loss) —The changes in each component of accumulated other comprehensive income (loss) consisted of the following: Accumulated Foreign currency other Change in translation Cash flow hedge comprehensive retirement plans adjustments adjustments (loss) income Balance — December 29, 2018 $ (4,392 ) $ (19,370 ) $ 146 $ (23,616 ) Foreign currency translation adjustment — 4,591 — 4,591 Loss on cash flow hedges — — (303 ) (303 ) Balance — June 29, 2019 $ (4,392 ) $ (14,779 ) $ (157 ) $ (19,328 ) Balance - December 30, 2017 $ (6,053 ) $ (10,022 ) $ (1,060 ) $ (17,135 ) Foreign currency translation adjustment — (5,149 ) — (5,149 ) Income on cash flow hedges — — 1,356 1,356 Balance - June 30, 2018 $ (6,053 ) $ (15,171 ) $ 296 $ (20,928 )

SUPPLEMENTAL CASH FLOW INFORMAT

SUPPLEMENTAL CASH FLOW INFORMATION	6 Months Ended
	Jun. 29, 2019
Schedule Of Cash Flow Supplemental [Line Items]
Supplemental Cash Flow Information	SUPPLEMENTAL CASH FLOW INFORMATION Supplemental cash flow information is as follows: Six months ended June 29, 2019 June 30, 2018 Cash payments: Interest $ 36,834 $ 52,206 Income taxes 1,190 3,061 Operating cash payments on operating leases 5,410 — Operating cash payments on finance leases 1,516 — Finance cash payments on finance leases 6,000 — Non cash financing activities: Right of use assets obtained in exchange for operating lease obligations $ 3,298 $ — Right of use assets obtained in exchange for finance leases obligations 16,248 — Exchange of LP Units to shares of Class A common stock 277 6,987
Summit Materials, LLC
Schedule Of Cash Flow Supplemental [Line Items]
Supplemental Cash Flow Information	SUPPLEMENTAL CASH FLOW INFORMATION Supplemental cash flow information is as follows: Six months ended June 29, 2019 June 30, 2018 Cash payments: Interest $ 36,834 $ 52,206 Income taxes 1,190 3,061 Operating cash payments on operating leases 5,410 — Operating cash payments on finance leases 1,516 — Finance cash payments on finance leases 6,000 — Non cash financing activities: Right of use assets obtained in exchange for operating lease obligations $ 3,298 $ — Right of use assets obtained in exchange for finance leases obligations 16,248 —

LEASES

LEASES	6 Months Ended
	Jun. 29, 2019
Lessee, Lease, Description [Line Items]
LEASES	LEASES We lease construction and office equipment, distribution facilities and office space. Leases with an initial term of 12 months or less, including month to month leases, are not recorded on the balance sheet. Lease expense for short-term leases is recognized on a straight line basis over the lease term. For lease agreements entered into or reassessed after the adoption of ASC 842, we combine lease and nonlease components. While we also own mineral leases for mining operations, those leases are outside the scope of ASC 842. Assets acquired under finance leases are included in property, plant and equipment. Many of our leases include options to purchase the leased equipment. The depreciable life of assets and leasehold improvements are limited by the expected lease term, unless there is a transfer of title or purchase option reasonably certain of exercise. Our lease agreements do not contain any material residual value guarantees or material restrictive covenants. The components of lease expense were as follows: Three months ended Six months ended June 29, 2019 June 29, 2019 Operating lease cost $ 2,694 $ 5,149 Variable lease cost 143 215 Short-term lease cost 9,591 16,172 Financing lease cost: Amortization of right-of-use assets 2,670 5,293 Interest on lease liabilities 876 1,631 Total lease cost $ 15,974 $ 28,460 June 29, 2019 Supplemental balance sheet information related to leases: Operating leases: Operating lease right-of-use assets $ 34,101 Current operating lease liabilities $ 8,470 Noncurrent operating lease liabilities 26,614 Total operating lease liabilities $ 35,084 Finance leases: Property and equipment, gross $ 79,911 Less accumulated depreciation (21,667 ) Property and equipment, net $ 58,244 Current finance lease liabilities $ 17,805 Long-term finance lease liabilities 41,123 Total finance lease liabilities $ 58,928 June 29, 2019 Lease Term Discount Rate (years) (%) Weighted average: Operating leases 7.7 5.6 % Finance lease 2.8 5.5 % Maturities of lease liabilities were as follows: Operating Leases Finance Leases 2019 (six months) $ 5,124 $ 10,115 2020 9,391 17,539 2021 7,434 20,235 2022 4,558 11,745 2023 3,546 1,509 2024 2,413 1,750 Thereafter 11,252 2,662 Total lease payments 43,718 65,555 Less imputed interest (8,634 ) (6,627 ) Present value of lease payments $ 35,084 $ 58,928 As previously disclosed, our future minimum lease payment obligations as of December 29, 2018 were as follows: Operating Leases 2019 $ 9,479 2020 8,101 2021 6,701 2022 4,279 2023 3,411
LEASES	LEASES We lease construction and office equipment, distribution facilities and office space. Leases with an initial term of 12 months or less, including month to month leases, are not recorded on the balance sheet. Lease expense for short-term leases is recognized on a straight line basis over the lease term. For lease agreements entered into or reassessed after the adoption of ASC 842, we combine lease and nonlease components. While we also own mineral leases for mining operations, those leases are outside the scope of ASC 842. Assets acquired under finance leases are included in property, plant and equipment. Many of our leases include options to purchase the leased equipment. The depreciable life of assets and leasehold improvements are limited by the expected lease term, unless there is a transfer of title or purchase option reasonably certain of exercise. Our lease agreements do not contain any material residual value guarantees or material restrictive covenants. The components of lease expense were as follows: Three months ended Six months ended June 29, 2019 June 29, 2019 Operating lease cost $ 2,694 $ 5,149 Variable lease cost 143 215 Short-term lease cost 9,591 16,172 Financing lease cost: Amortization of right-of-use assets 2,670 5,293 Interest on lease liabilities 876 1,631 Total lease cost $ 15,974 $ 28,460 June 29, 2019 Supplemental balance sheet information related to leases: Operating leases: Operating lease right-of-use assets $ 34,101 Current operating lease liabilities $ 8,470 Noncurrent operating lease liabilities 26,614 Total operating lease liabilities $ 35,084 Finance leases: Property and equipment, gross $ 79,911 Less accumulated depreciation (21,667 ) Property and equipment, net $ 58,244 Current finance lease liabilities $ 17,805 Long-term finance lease liabilities 41,123 Total finance lease liabilities $ 58,928 June 29, 2019 Lease Term Discount Rate (years) (%) Weighted average: Operating leases 7.7 5.6 % Finance lease 2.8 5.5 % Maturities of lease liabilities were as follows: Operating Leases Finance Leases 2019 (six months) $ 5,124 $ 10,115 2020 9,391 17,539 2021 7,434 20,235 2022 4,558 11,745 2023 3,546 1,509 2024 2,413 1,750 Thereafter 11,252 2,662 Total lease payments 43,718 65,555 Less imputed interest (8,634 ) (6,627 ) Present value of lease payments $ 35,084 $ 58,928 As previously disclosed, our future minimum lease payment obligations as of December 29, 2018 were as follows: Operating Leases 2019 $ 9,479 2020 8,101 2021 6,701 2022 4,279 2023 3,411
Summit Materials, LLC
Lessee, Lease, Description [Line Items]
LEASES	LEASES We lease construction and office equipment, distribution facilities and office space. Leases with an initial term of 12 months or less, including month to month leases, are not recorded on the balance sheet. Lease expense for short-term leases is recognized on a straight line basis over the lease term. For lease agreements entered into or reassessed after the adoption of ASC 842, we combine lease and nonlease components. While we also own mineral leases for mining operations, those leases are outside the scope of ASC 842. Assets acquired under finance leases are included in property, plant and equipment. Many of our leases include options to purchase the leased equipment. The depreciable life of assets and leasehold improvements are limited by the expected lease term, unless there is a transfer of title or purchase option reasonably certain of exercise. Our lease agreements do not contain any material residual value guarantees or material restrictive covenants. The components of lease expense were as follows: Three months ended Six months ended June 29, 2019 June 29, 2019 Operating lease cost $ 2,694 $ 5,149 Variable lease cost 143 215 Short-term lease cost 9,591 16,172 Financing lease cost: Amortization of right-of-use assets 2,670 5,293 Interest on lease liabilities 876 1,631 Total lease cost $ 15,974 $ 28,460 June 29, 2019 Supplemental balance sheet information related to leases: Operating leases: Operating lease right-of-use assets $ 34,101 Current operating lease liabilities $ 8,470 Noncurrent operating lease liabilities 26,614 Total operating lease liabilities $ 35,084 Finance leases: Property and equipment, gross $ 79,911 Less accumulated depreciation (21,667 ) Property and equipment, net $ 58,244 Current finance lease liabilities $ 17,805 Long-term finance lease liabilities 41,123 Total finance lease liabilities $ 58,928 June 29, 2019 Lease Term Discount Rate (years) (%) Weighted average: Operating leases 7.7 5.6 % Finance lease 2.8 5.5 % Maturities of lease liabilities were as follows: Operating Leases Finance Leases 2019 (six months) $ 5,124 $ 10,115 2020 9,391 17,539 2021 7,434 20,235 2022 4,558 11,745 2023 3,546 1,509 2024 2,413 1,750 Thereafter 11,252 2,662 Total lease payments 43,718 65,555 Less imputed interest (8,634 ) (6,627 ) Present value of lease payments $ 35,084 $ 58,928 As previously disclosed, our future minimum lease payment obligations as of December 29, 2018 were as follows: Operating Leases 2019 $ 9,479 2020 8,101 2021 6,701 2022 4,279 2023 3,411
LEASES	LEASES We lease construction and office equipment, distribution facilities and office space. Leases with an initial term of 12 months or less, including month to month leases, are not recorded on the balance sheet. Lease expense for short-term leases is recognized on a straight line basis over the lease term. For lease agreements entered into or reassessed after the adoption of ASC 842, we combine lease and nonlease components. While we also own mineral leases for mining operations, those leases are outside the scope of ASC 842. Assets acquired under finance leases are included in property, plant and equipment. Many of our leases include options to purchase the leased equipment. The depreciable life of assets and leasehold improvements are limited by the expected lease term, unless there is a transfer of title or purchase option reasonably certain of exercise. Our lease agreements do not contain any material residual value guarantees or material restrictive covenants. The components of lease expense were as follows: Three months ended Six months ended June 29, 2019 June 29, 2019 Operating lease cost $ 2,694 $ 5,149 Variable lease cost 143 215 Short-term lease cost 9,591 16,172 Financing lease cost: Amortization of right-of-use assets 2,670 5,293 Interest on lease liabilities 876 1,631 Total lease cost $ 15,974 $ 28,460 June 29, 2019 Supplemental balance sheet information related to leases: Operating leases: Operating lease right-of-use assets $ 34,101 Current operating lease liabilities $ 8,470 Noncurrent operating lease liabilities 26,614 Total operating lease liabilities $ 35,084 Finance leases: Property and equipment, gross $ 79,911 Less accumulated depreciation (21,667 ) Property and equipment, net $ 58,244 Current finance lease liabilities $ 17,805 Long-term finance lease liabilities 41,123 Total finance lease liabilities $ 58,928 June 29, 2019 Lease Term Discount Rate (years) (%) Weighted average: Operating leases 7.7 5.6 % Finance lease 2.8 5.5 % Maturities of lease liabilities were as follows: Operating Leases Finance Leases 2019 (six months) $ 5,124 $ 10,115 2020 9,391 17,539 2021 7,434 20,235 2022 4,558 11,745 2023 3,546 1,509 2024 2,413 1,750 Thereafter 11,252 2,662 Total lease payments 43,718 65,555 Less imputed interest (8,634 ) (6,627 ) Present value of lease payments $ 35,084 $ 58,928 As previously disclosed, our future minimum lease payment obligations as of December 29, 2018 were as follows: Operating Leases 2019 $ 9,479 2020 8,101 2021 6,701 2022 4,279 2023 3,411

FAIR VALUE

FAIR VALUE	6 Months Ended
	Jun. 29, 2019
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	FAIR VALUE Fair Value Measurements— Certain acquisitions made by the Company require the payment of contingent amounts of purchase consideration. These payments are contingent on specified operating results being achieved in periods subsequent to the acquisition and will only be made if earn-out thresholds are achieved. Contingent consideration obligations are measured at fair value each reporting period. Any adjustments to fair value are recognized in earnings in the period identified. The Company has entered into interest rate derivatives on $200.0 million of its term loan borrowings to add stability to interest expense and to manage its exposure to interest rate movements. The interest rate derivative expires in September 2019. The effective portion of changes in the fair value of derivatives designated and that qualify as cash flow hedges is recorded in accumulated other comprehensive income (loss) and will be subsequently reclassified into earnings in the period that the hedged forecasted transaction affects earnings. The fair value of contingent consideration and derivatives as of June 29, 2019 and December 29, 2018 was: June 29, 2019 December 29, 2018 Current portion of acquisition-related liabilities and Accrued expenses: Contingent consideration $ 2,622 $ 1,394 Cash flow hedges 112 — Acquisition-related liabilities and Other noncurrent liabilities: Contingent consideration $ 1,238 $ 5,175 Cash flow hedges — — The fair value of contingent consideration was based on unobservable, or Level 3, inputs, including projected probability-weighted cash payments and a 10.0% discount rate, which reflects a market discount rate. Changes in fair value may occur as a result of a change in actual or projected cash payments, the probability weightings applied by the Company to projected payments or a change in the discount rate. Significant increases or decreases in any of these inputs in isolation could result in a lower, or higher, fair value measurement. The fair value of the cash flow hedges is based on observable, or Level 2, inputs such as interest rates, bond yields and prices in inactive markets. There were no material valuation adjustments to contingent consideration or derivatives as of June 29, 2019 and June 30, 2018 . Financial Instruments —The Company’s financial instruments include debt and certain acquisition-related liabilities (deferred consideration and noncompete obligations). The carrying value and fair value of these financial instruments as of June 29, 2019 and December 29, 2018 was: June 29, 2019 December 29, 2018 Fair Value Carrying Value Fair Value Carrying Value Level 2 Long-term debt(1) $ 1,895,932 $ 1,873,627 $ 1,777,722 $ 1,828,159 Level 3 Current portion of deferred consideration and noncompete obligations(2) 32,848 32,848 32,876 32,876 Long term portion of deferred consideration and noncompete obligations(3) 38,850 38,850 44,293 44,293 (1) $4.8 million and $6.4 million were included in current portion of debt as of June 29, 2019 and December 29, 2018 , respectively. (2) Included in current portion of acquisition-related liabilities on the consolidated balance sheets. (3) Included in acquisition-related liabilities on the consolidated balance sheets. The fair value of debt was determined based on observable, or Level 2, inputs, such as interest rates, bond yields and quoted prices in inactive markets. The fair values of the deferred consideration and noncompete obligations were determined based on unobservable, or Level 3, inputs, including the cash payment terms in the purchase agreements and a discount rate reflecting the Company’s credit risk. The discount rate used is generally consistent with that used when the obligations were initially recorded. Securities with a maturity of three months or less are considered cash equivalents and the fair value of these assets approximates their carrying value.
Summit Materials, LLC
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value	FAIR VALUE Fair Value Measurements— Certain acquisitions made by the Company require the payment of contingent amounts of purchase consideration. These payments are contingent on specified operating results being achieved in periods subsequent to the acquisition and will only be made if earn-out thresholds are achieved. Contingent consideration obligations are measured at fair value each reporting period. Any adjustments to fair value are recognized in earnings in the period identified. The Company has entered into interest rate derivatives on $200.0 million of its term loan borrowings to add stability to interest expense and to manage its exposure to interest rate movements. The interest rate derivative expires in September 2019. The effective portion of changes in the fair value of derivatives designated and that qualify as cash flow hedges is recorded in accumulated other comprehensive income (loss) and will be subsequently reclassified into earnings in the period that the hedged forecasted transaction affects earnings. The fair value of contingent consideration and derivatives as of June 29, 2019 and December 29, 2018 was: June 29, 2019 December 29, 2018 Current portion of acquisition-related liabilities and Accrued expenses: Contingent consideration $ 2,622 $ 1,394 Cash flow hedges 112 — Acquisition-related liabilities and Other noncurrent liabilities: Contingent consideration $ 1,238 $ 5,175 Cash flow hedges — — The fair value of contingent consideration was based on unobservable, or Level 3, inputs, including projected probability-weighted cash payments and a 10.0% discount rate, which reflects a market discount rate. Changes in fair value may occur as a result of a change in actual or projected cash payments, the probability weightings applied by the Company to projected payments or a change in the discount rate. Significant increases or decreases in any of these inputs in isolation could result in a lower, or higher, fair value measurement. The fair value of the cash flow hedges is based on observable, or Level 2, inputs such as interest rates, bond yields and prices in inactive markets. There were no material valuation adjustments to contingent consideration or derivatives as of June 29, 2019 and June 30, 2018 . Financial Instruments —The Company’s financial instruments include debt and certain acquisition-related liabilities (deferred consideration and noncompete obligations). The carrying value and fair value of these financial instruments as of June 29, 2019 and December 29, 2018 was: June 29, 2019 December 29, 2018 Fair Value Carrying Value Fair Value Carrying Value Level 2 Long-term debt(1) $ 1,895,932 $ 1,873,627 $ 1,777,722 $ 1,828,159 Level 3 Current portion of deferred consideration and noncompete obligations(2) 30,348 30,348 30,376 30,376 Long term portion of deferred consideration and noncompete obligations(3) 36,951 36,951 40,179 40,179 (1) $4.8 million and $6.4 million were included in current portion of debt as of June 29, 2019 and December 29, 2018 , respectively. (2) Included in current portion of acquisition-related liabilities on the consolidated balance sheets. (3) Included in acquisition-related liabilities on the consolidated balance sheets. The fair value of debt was determined based on observable, or Level 2 inputs, such as interest rates, bond yields and quoted prices in inactive markets. The fair values of the deferred consideration and noncompete obligations were determined based on unobservable, or Level 3, inputs, including the cash payment terms in the purchase agreements and a discount rate reflecting the Company’s credit risk. The discount rate used is generally consistent with that used when the obligations were initially recorded. Securities with a maturity of three months or less are considered cash equivalents and the fair value of these assets approximates their carrying value.

COMMITMENTS AND CONTINGENCIES

COMMITMENTS AND CONTINGENCIES	6 Months Ended
	Jun. 29, 2019
Loss Contingencies [Line Items]
Commitments and Contingencies	COMMITMENTS AND CONTINGENCIES The Company is party to certain legal actions arising from the ordinary course of business activities. Accruals are recorded when the outcome is probable and can be reasonably estimated. While the ultimate results of claims and litigation cannot be predicted with certainty, management expects that the ultimate resolution of all current pending or threatened claims and litigation will not have a material effect on the Company’s consolidated financial position, results of operations or liquidity. The Company records legal fees as incurred. In March 2018, we were notified of an investigation by the Canadian Competition Bureau (the “CCB”) into pricing practices by certain asphalt paving contractors in British Columbia, including Winvan Paving, Ltd. (“Winvan”). We believe the investigation is focused on time periods prior to our April 2017 acquisition of Winvan and we are cooperating with the CCB. Environmental Remediation and Site Restoration —The Company’s operations are subject to and affected by federal, state, provincial and local laws and regulations relating to the environment, health and safety and other regulatory matters. These operations require environmental operating permits, which are subject to modification, renewal and revocation. The Company regularly monitors and reviews its operations, procedures and policies for compliance with these laws and regulations. Despite these compliance efforts, risk of environmental liability is inherent in the operation of the Company’s business, as it is with other companies engaged in similar businesses and there can be no assurance that environmental liabilities or noncompliance will not have a material adverse effect on the Company’s consolidated financial condition, results of operations or liquidity. The Company has asset retirement obligations arising from regulatory and contractual requirements to perform reclamation activities at the time certain quarries and landfills are closed. As of June 29, 2019 and December 29, 2018 , $28.6 million and $26.9 million , respectively, were included in other noncurrent liabilities on the consolidated balance sheets and $3.5 million and $4.1 million , respectively, were included in accrued expenses for future reclamation costs. The total undiscounted anticipated costs for site reclamation as of June 29, 2019 and December 29, 2018 were $90.2 million and $92.5 million , respectively. Other —The Company is obligated under various firm purchase commitments for certain raw materials and services that are in the ordinary course of business. Management does not expect any significant changes in the market value of these goods and services during the commitment period that would have a material adverse effect on the financial condition, results of operations and cash flows of the Company. The terms of the purchase commitments generally approximate one year .
Summit Materials, LLC
Loss Contingencies [Line Items]
Commitments and Contingencies	COMMITMENTS AND CONTINGENCIES The Company is party to certain legal actions arising from the ordinary course of business activities. Accruals are recorded when the outcome is probable and can be reasonably estimated. While the ultimate results of claims and litigation cannot be predicted with certainty, management expects that the ultimate resolution of all current pending or threatened claims and litigation will not have a material effect on the Company’s consolidated financial position, results of operations or liquidity. The Company records legal fees as incurred. In March 2018, we were notified of an investigation by the Canadian Competition Bureau (the “CCB”) into pricing practices by certain asphalt paving contractors in British Columbia, including Winvan Paving, Ltd. (“Winvan”). We believe the investigation is focused on time periods prior to our April 2017 acquisition of Winvan and we are cooperating with the CCB. Environmental Remediation and Site Restoration —The Company’s operations are subject to and affected by federal, state, provincial and local laws and regulations relating to the environment, health and safety and other regulatory matters. These operations require environmental operating permits, which are subject to modification, renewal and revocation. The Company regularly monitors and reviews its operations, procedures and policies for compliance with these laws and regulations. Despite these compliance efforts, risk of environmental liability is inherent in the operation of the Company’s business, as it is with other companies engaged in similar businesses and there can be no assurance that environmental liabilities or noncompliance will not have a material adverse effect on the Company’s consolidated financial condition, results of operations or liquidity. The Company has asset retirement obligations arising from regulatory and contractual requirements to perform reclamation activities at the time certain quarries and landfills are closed. As of June 29, 2019 and December 29, 2018 , $28.6 million and $26.9 million , respectively, were included in other noncurrent liabilities on the consolidated balance sheets and $3.5 million and $4.1 million , respectively, were included in accrued expenses for future reclamation costs. The total undiscounted anticipated costs for site reclamation as of June 29, 2019 and December 29, 2018 were $90.2 million and $92.5 million , respectively. Other —The Company is obligated under various firm purchase commitments for certain raw materials and services that are in the ordinary course of business. Management does not expect any significant changes in the market value of these goods and services during the commitment period that would have a material adverse effect on the financial condition, results of operations and cash flows of the Company. The terms of the purchase commitments generally approximate one year .

SEGMENT INFORMATION

SEGMENT INFORMATION	6 Months Ended
	Jun. 29, 2019
Segment Reporting Information [Line Items]
Segment Information	SEGMENT INFORMATION The Company has three operating segments: West, East and Cement, which are its reporting segments. These segments are consistent with the Company’s management reporting structure. The operating results of each segment are regularly reviewed and evaluated by the Chief Executive Officer, our Company’s Chief Operating Decision Maker (“CODM”). The CODM primarily evaluates the performance of the Company’s segments and allocates resources to them based on a segment profit metric that we call Adjusted EBITDA, which is computed as earnings from continuing operations before interest, taxes, depreciation, depletion, amortization, accretion, share-based compensation, and transaction costs, as well as various other non-recurring, non-cash amounts. The West and East segments have several acquired subsidiaries that are engaged in various activities including quarry mining, aggregate production and contracting. The Cement segment is engaged in the production of Portland cement. Assets employed by each segment include assets directly identified with those operations. Corporate assets consist primarily of cash, property, plant and equipment for corporate operations and other assets not directly identifiable with a reportable business segment. The accounting policies applicable to each segment are consistent with those used in the consolidated financial statements. The following tables display selected financial data for the Company’s reportable business segments as of June 29, 2019 and December 29, 2018 and for the three and six months ended June 29, 2019 and June 30, 2018 : Three months ended Six months ended June 29, 2019 June 30, 2018 June 29, 2019 June 30, 2018 Revenue*: West $ 300,212 $ 321,713 $ 482,157 $ 503,426 East 216,132 197,336 329,520 292,493 Cement 84,547 81,841 121,853 119,392 Total revenue $ 600,891 $ 600,890 $ 933,530 $ 915,311 *Intercompany sales are immaterial and the presentation above only reflects sales to external customers. Three months ended Six months ended June 29, 2019 June 30, 2018 June 29, 2019 June 30, 2018 Income (loss) from operation before taxes $ 54,697 $ 49,103 $ (44,841 ) $ (23,551 ) Interest expense 29,401 28,943 59,506 57,727 Depreciation, depletion and amortization 53,035 49,402 107,842 95,945 Accretion 590 329 1,171 744 Loss on debt financings — 149 14,565 149 Transaction costs 390 1,291 698 2,557 Non-cash compensation 4,699 5,683 10,605 14,190 Other (2,346 ) 441 (2,492 ) (6,907 ) Total Adjusted EBITDA $ 140,466 $ 135,341 $ 147,054 $ 140,854 Total Adjusted EBITDA by Segment: West $ 54,820 $ 61,227 $ 69,118 $ 77,400 East 54,412 45,395 57,654 42,192 Cement 35,441 34,660 32,854 38,327 Corporate and other (4,207 ) (5,941 ) (12,572 ) (17,065 ) Total Adjusted EBITDA $ 140,466 $ 135,341 $ 147,054 $ 140,854 Six months ended June 29, 2019 June 30, 2018 Purchases of property, plant and equipment West $ 51,517 $ 76,223 East 41,801 37,303 Cement 11,467 14,412 Total reportable segments 104,785 127,938 Corporate and other 784 3,719 Total purchases of property, plant and equipment $ 105,569 $ 131,657 Three months ended Six months ended June 29, 2019 June 30, 2018 June 29, 2019 June 30, 2018 Depreciation, depletion, amortization and accretion: West $ 22,924 $ 22,589 $ 46,849 $ 44,740 East 19,840 17,826 40,051 35,553 Cement 9,869 8,681 20,169 15,051 Total reportable segments 52,633 49,096 107,069 95,344 Corporate and other 992 635 1,944 1,345 Total depreciation, depletion, amortization and accretion $ 53,625 $ 49,731 $ 109,013 $ 96,689 June 29, 2019 December 29, 2018 Total assets: West $ 1,437,583 $ 1,370,501 East 1,307,364 1,253,640 Cement 887,751 877,586 Total reportable segments 3,632,698 3,501,727 Corporate and other 322,158 355,914 Total $ 3,954,856 $ 3,857,641
Summit Materials, LLC
Segment Reporting Information [Line Items]
Segment Information	SEGMENT INFORMATION The Company has three operating segments: West, East, and Cement, which are its reporting segments. These segments are consistent with the Company’s management reporting structure. The operating results of each segment are regularly reviewed and evaluated by the Chief Executive Officer, our Company’s Chief Operating Decision Maker (“CODM”). The CODM primarily evaluates the performance of the Company’s segments and allocates resources to them based on a segment profit metric that we call Adjusted EBITDA, which is computed as earnings from continuing operations before interest, taxes, depreciation, depletion, amortization, accretion, share-based compensation, and transaction costs, as well as various other non-recurring, non-cash amounts. The West and East segments have several acquired subsidiaries that are engaged in various activities including quarry mining, aggregate production and contracting. The Cement segment is engaged in the production of Portland cement. Assets employed by each segment include assets directly identified with those operations. Corporate assets consist primarily of cash, property, plant and equipment for corporate operations and other assets not directly identifiable with a reportable business segment. The accounting policies applicable to each segment are consistent with those used in the consolidated financial statements. The following tables display selected financial data for the Company’s reportable business segments as of June 29, 2019 and December 29, 2018 and for the three and six months ended June 29, 2019 and June 30, 2018 : Three months ended Six months ended June 29, June 30, June 29, June 30, 2019 2018 2019 2018 Revenue*: West $ 300,212 $ 321,713 $ 482,157 $ 503,426 East 216,132 197,336 329,520 292,493 Cement 84,547 81,841 121,853 119,392 Total revenue $ 600,891 $ 600,890 $ 933,530 $ 915,311 *Intercompany sales are immaterial and the presentation above only reflects sales to external customers. Three months ended Six months ended June 29, June 30, June 29, June 30, 2019 2018 2019 2018 Income (loss) from operation before taxes $ 54,815 $ 49,270 $ (44,555 ) $ (23,170 ) Interest expense 29,283 28,776 59,220 57,346 Depreciation, depletion and amortization 53,035 49,402 107,842 95,945 Accretion 590 329 1,171 744 Loss on debt financings — 149 14,565 149 Transaction costs 390 1,291 698 2,557 Non-cash compensation 4,699 5,683 10,605 14,190 Other (2,346 ) 441 (2,492 ) (6,907 ) Total Adjusted EBITDA $ 140,466 $ 135,341 $ 147,054 $ 140,854 Total Adjusted EBITDA by Segment: West $ 54,820 $ 61,227 $ 69,118 $ 77,400 East 54,412 45,395 57,654 42,192 Cement 35,441 34,660 32,854 38,327 Corporate and other (4,207 ) (5,941 ) (12,572 ) (17,065 ) Total Adjusted EBITDA $ 140,466 $ 135,341 $ 147,054 $ 140,854 Six months ended June 29, 2019 June 30, 2018 Purchases of property, plant and equipment West $ 51,517 $ 76,223 East 41,801 37,303 Cement 11,467 14,412 Total reportable segments 104,785 127,938 Corporate and other 784 3,719 Total purchases of property, plant and equipment $ 105,569 $ 131,657 Three months ended Six months ended June 29, June 30, June 29, June 30, 2019 2018 2019 2018 Depreciation, depletion, amortization and accretion: West $ 22,924 $ 22,589 $ 46,849 $ 44,740 East 19,840 17,826 40,051 35,553 Cement 9,869 8,681 20,169 15,051 Total reportable segments 52,633 49,096 107,069 95,344 Corporate and other 992 635 1,944 1,345 Total depreciation, depletion, amortization and accretion $ 53,625 $ 49,731 $ 109,013 $ 96,689 June 29, 2019 December 29, 2018 Total assets: West $ 1,437,583 $ 1,370,501 East 1,307,364 1,253,640 Cement 887,751 877,586 Total reportable segments 3,632,698 3,501,727 Corporate and other 86,069 131,517 Total $ 3,718,767 $ 3,633,244

GUARANTOR AND NON-GUARANTOR FIN

GUARANTOR AND NON-GUARANTOR FINANCIAL INFORMATION	6 Months Ended
	Jun. 29, 2019
Summit Materials, LLC
Guarantor and Non-Guarantor Financial Information	GUARANTOR AND NON-GUARANTOR FINANCIAL INFORMATION Summit LLC’s domestic wholly-owned subsidiary companies other than Finance Corp. are named as guarantors (collectively, the “Guarantors”) of the Senior Notes. Finance Corp. does not and will not have any assets or operations other than as may be incidental to its activities as a co-issuer of the Senior Notes and other indebtedness. Certain other partially-owned subsidiaries and a non-U.S. entity do not guarantee the Senior Notes (collectively, the “Non-Guarantors”). The Guarantors provide a joint and several, full and unconditional guarantee of the Senior Notes. There are no significant restrictions on Summit LLC’s ability to obtain funds from any of the Guarantor Subsidiaries in the form of dividends or loans. Additionally, there are no significant restrictions on a Guarantor Subsidiary’s ability to obtain funds from Summit LLC or its direct or indirect subsidiaries. The following condensed consolidating balance sheets, statements of operations and cash flows are provided for the Issuers, the wholly-owned guarantors and the Non-Guarantors. Earnings from subsidiaries are included in other income in the condensed consolidated statements of operations below. The financial information may not necessarily be indicative of the financial position, results of operations or cash flows had the guarantor or non-guarantor subsidiaries operated as independent entities. Condensed Consolidating Balance Sheets June 29, 2019 100% Owned Non- Issuers Guarantors Guarantors Eliminations Consolidated Assets Current assets: Cash and cash equivalents $ 69,466 $ 3,712 $ 782 $ (6,302 ) $ 67,658 Accounts receivable, net — 274,291 20,531 (218 ) 294,604 Intercompany receivables 465,120 640,478 — (1,105,598 ) — Cost and estimated earnings in excess of billings — 43,308 2,063 — 45,371 Inventories — 204,291 3,845 — 208,136 Other current assets 1,279 8,025 3,314 — 12,618 Total current assets 535,865 1,174,105 30,535 (1,112,118 ) 628,387 Property, plant and equipment, net 12,008 1,713,138 63,518 — 1,788,664 Goodwill — 1,140,580 58,597 — 1,199,177 Intangible assets, net — 17,653 — — 17,653 Operating lease right-of-use assets 3,653 25,015 5,433 — 34,101 Other assets 3,367,863 158,299 823 (3,476,200 ) 50,785 Total assets $ 3,919,389 $ 4,228,790 $ 158,906 $ (4,588,318 ) $ 3,718,767 Liabilities and Member’s Interest Current liabilities: Current portion of debt $ 4,765 $ — $ — $ — $ 4,765 Current portion of acquisition-related liabilities — 32,970 — — 32,970 Accounts payable 2,367 118,300 11,553 (218 ) 132,002 Accrued expenses 47,231 70,818 2,481 (6,302 ) 114,228 Current operating lease liabilities 735 6,681 1,054 — 8,470 Intercompany payables 642,397 445,051 18,150 (1,105,598 ) — Billings in excess of costs and estimated earnings — 9,897 836 — 10,733 Total current liabilities 697,495 683,717 34,074 (1,112,118 ) 303,168 Long-term debt 1,854,189 — — — 1,854,189 Acquisition-related liabilities — 38,189 — — 38,189 Noncurrent operating lease liabilities 3,867 18,454 4,293 — 26,614 Other noncurrent liabilities 3,794 192,351 77,438 (137,020 ) 136,563 Total liabilities 2,559,345 932,711 115,805 (1,249,138 ) 2,358,723 Total member's interest 1,360,044 3,296,079 43,101 (3,339,180 ) 1,360,044 Total liabilities and member’s interest $ 3,919,389 $ 4,228,790 $ 158,906 $ (4,588,318 ) $ 3,718,767 Condensed Consolidating Balance Sheets December 29, 2018 100% Owned Non- Issuers Guarantors Guarantors Eliminations Consolidated Assets Current assets: Cash and cash equivalents $ 117,219 $ 8,440 $ 7,719 $ (4,870 ) $ 128,508 Accounts receivable, net — 199,538 15,165 (185 ) 214,518 Intercompany receivables 500,765 624,427 — (1,125,192 ) — Cost and estimated earnings in excess of billings — 17,711 891 — 18,602 Inventories — 210,149 3,702 — 213,851 Other current assets 1,953 11,308 2,800 — 16,061 Total current assets 619,937 1,071,573 30,277 (1,130,247 ) 591,540 Property, plant and equipment, net 13,300 1,709,083 57,749 — 1,780,132 Goodwill — 1,136,785 56,243 — 1,193,028 Intangible assets, net — 18,460 — — 18,460 Other assets 3,292,851 154,080 947 (3,397,794 ) 50,084 Total assets $ 3,926,088 $ 4,089,981 $ 145,216 $ (4,528,041 ) $ 3,633,244 Liabilities and Member’s Interest Current liabilities: Current portion of debt $ 6,354 $ — $ — $ — $ 6,354 Current portion of acquisition-related liabilities — 31,770 — — 31,770 Accounts payable 4,712 92,132 12,349 (185 ) 109,008 Accrued expenses 45,146 57,826 1,927 (4,870 ) 100,029 Intercompany payables 673,175 436,564 15,453 (1,125,192 ) — Billings in excess of costs and estimated earnings — 11,347 493 — 11,840 Total current liabilities 729,387 629,639 30,222 (1,130,247 ) 259,001 Long-term debt 1,807,502 — — — 1,807,502 Acquisition-related liabilities — 45,354 — — 45,354 Other noncurrent liabilities 3,768 226,137 77,368 (171,317 ) 135,956 Total liabilities 2,540,657 901,130 107,590 (1,301,564 ) 2,247,813 Total member's interest 1,385,431 3,188,851 37,626 (3,226,477 ) 1,385,431 Total liabilities and member’s interest $ 3,926,088 $ 4,089,981 $ 145,216 $ (4,528,041 ) $ 3,633,244 Condensed Consolidating Statements of Operations For the three months ended June 29, 2019 100% Owned Non- Issuers Guarantors Guarantors Eliminations Consolidated Revenue $ — $ 578,157 $ 25,495 $ (2,761 ) $ 600,891 Cost of revenue (excluding items shown separately below) — 390,640 17,614 (2,761 ) 405,493 General and administrative expenses 9,353 49,288 2,710 — 61,351 Depreciation, depletion, amortization and accretion 992 51,167 1,466 — 53,625 Operating (loss) income (10,345 ) 87,062 3,705 — 80,422 Other income, net (95,320 ) (2,985 ) (372 ) 95,001 (3,676 ) Interest expense (income) 31,022 (2,947 ) 1,208 — 29,283 Income from operation before taxes 53,953 92,994 2,869 (95,001 ) 54,815 Income tax expense 452 85 777 — 1,314 Net income attributable to Summit LLC $ 53,501 $ 92,909 $ 2,092 $ (95,001 ) $ 53,501 Comprehensive income (loss) attributable to member of Summit Materials, LLC $ 55,597 $ 93,046 $ (141 ) $ (92,905 ) $ 55,597 Condensed Consolidating Statements of Operations For the six months ended June 29, 2019 100% Owned Non- Issuers Guarantors Guarantors Eliminations Consolidated Revenue $ — $ 896,338 $ 41,136 $ (3,944 ) $ 933,530 Cost of revenue (excluding items shown separately below) — 646,807 29,634 (3,944 ) 672,497 General and administrative expenses 24,284 99,319 5,666 — 129,269 Depreciation, depletion, amortization and accretion 1,945 104,087 2,981 — 109,013 Operating (loss) income (26,229 ) 46,125 2,855 — 22,751 Other (income) loss, net (51,710 ) (4,926 ) (775 ) 65,497 8,086 Interest expense (income) 62,718 (5,911 ) 2,413 — 59,220 (Loss) income from operation before taxes (37,237 ) 56,962 1,217 (65,497 ) (44,555 ) Income tax expense (benefit) 826 (7,652 ) 334 — (6,492 ) Net (loss) income attributable to Summit LLC $ (38,063 ) $ 64,614 $ 883 $ (65,497 ) $ (38,063 ) Comprehensive (loss) income attributable to member of Summit Materials, LLC $ (33,775 ) $ 64,917 $ (3,708 ) $ (61,209 ) $ (33,775 ) Condensed Consolidating Statements of Operations For the three months ended June 30, 2018 100% Owned Non- Issuers Guarantors Guarantors Eliminations Consolidated Revenue $ — $ 580,157 $ 22,352 $ (1,619 ) $ 600,890 Cost of revenue (excluding items shown separately below) — 396,629 15,922 (1,619 ) 410,932 General and administrative expenses 13,276 47,287 2,385 — 62,948 Depreciation, depletion, amortization and accretion 635 47,929 1,167 — 49,731 Operating (loss) income (13,911 ) 88,312 2,878 — 77,279 Other (income) loss, net (89,659 ) (687 ) 98 89,481 (767 ) Interest expense (income) 28,946 (1,362 ) 1,192 — 28,776 Income from operation before taxes 46,802 90,361 1,588 (89,481 ) 49,270 Income tax expense 200 2,036 432 — 2,668 Net income attributable to Summit LLC $ 46,602 $ 88,325 $ 1,156 $ (89,481 ) $ 46,602 Comprehensive income attributable to member of Summit Materials, LLC $ 44,918 $ 87,964 $ 3,201 $ (91,165 ) $ 44,918 Condensed Consolidating Statements of Operations For the six months ended June 30, 2018 100% Owned Non- Issuers Guarantors Guarantors Eliminations Consolidated Revenue $ — $ 880,815 $ 37,533 $ (3,037 ) $ 915,311 Cost of revenue (excluding items shown separately below) — 634,756 27,074 (3,037 ) 658,793 General and administrative expenses 34,224 94,463 5,388 — 134,075 Depreciation, depletion, amortization and accretion 1,345 92,922 2,422 — 96,689 Operating (loss) income (35,569 ) 58,674 2,649 — 25,754 Other (income) loss, net (72,294 ) (7,544 ) 149 71,267 (8,422 ) Interest expense (income) 58,527 (3,565 ) 2,384 — 57,346 (Loss) income from operation before taxes (21,802 ) 69,783 116 (71,267 ) (23,170 ) Income tax expense (benefit) 192 (1,417 ) 49 — (1,176 ) Net (loss) income attributable to Summit LLC $ (21,994 ) $ 71,200 $ 67 $ (71,267 ) $ (21,994 ) Comprehensive (loss) income attributable to member of Summit Materials, LLC $ (25,787 ) $ 69,844 $ 5,216 $ (75,060 ) $ (25,787 ) Condensed Consolidating Statements of Cash Flows For the six months ended June 29, 2019 100% Owned Non- Issuers Guarantors Guarantors Eliminations Consolidated Net cash (used in) provided by operating activities $ (43,760 ) $ 59,190 $ 518 $ — $ 15,948 Cash flow from investing activities: Acquisitions, net of cash acquired — (2,842 ) — — (2,842 ) Purchase of property, plant and equipment (785 ) (96,883 ) (7,901 ) — (105,569 ) Proceeds from the sale of property, plant, and equipment — 7,940 65 — 8,005 Other — (439 ) — — (439 ) Net cash used for investing activities (785 ) (92,224 ) (7,836 ) — (100,845 ) Cash flow from financing activities: Proceeds from investment by member (36,356 ) 37,140 — — 784 Net proceeds from debt issuance 300,000 — — — 300,000 Loans received from and payments made on loans from other Summit Companies (2,879 ) 3,997 314 (1,432 ) — Payments on long-term debt (254,765 ) (6,133 ) (127 ) — (261,025 ) Payments on acquisition-related liabilities — (6,658 ) — — (6,658 ) Debt issuance costs (6,246 ) — — — (6,246 ) Distributions from partnership (2,500 ) — — — (2,500 ) Other (462 ) (40 ) — — (502 ) Net cash (used in) provided by financing activities (3,208 ) 28,306 187 (1,432 ) 23,853 Impact of cash on foreign currency — — 194 — 194 Net decrease in cash (47,753 ) (4,728 ) (6,937 ) (1,432 ) (60,850 ) Cash — Beginning of period 117,219 8,440 7,719 (4,870 ) 128,508 Cash — End of period $ 69,466 $ 3,712 $ 782 $ (6,302 ) $ 67,658 Condensed Consolidating Statements of Cash Flows For the six months ended June 30, 2018 100% Owned Non- Issuers Guarantors Guarantors Eliminations Consolidated Net cash (used in) provided by operating activities $ (70,942 ) $ 34,740 $ 2,484 $ — $ (33,718 ) Cash flow from investing activities: Acquisitions, net of cash acquired — (153,196 ) — — (153,196 ) Purchase of property, plant and equipment (3,718 ) (115,967 ) (11,972 ) — (131,657 ) Proceeds from the sale of property, plant, and equipment — 13,950 160 — 14,110 Other — 684 — — 684 Net cash used for investing activities (3,718 ) (254,529 ) (11,812 ) — (270,059 ) Cash flow from financing activities: Proceeds from investment by member (100,271 ) 115,886 — — 15,615 Loans received from and payments made on loans from other Summit Companies (135,634 ) 136,483 (2,033 ) 1,184 — Payments on long-term debt (3,178 ) (7,587 ) (7 ) — (10,772 ) Payments on acquisition-related liabilities — (28,724 ) — — (28,724 ) Financing costs (550 ) — — — (550 ) Distributions from partnership (2,569 ) — — — (2,569 ) Other (876 ) (995 ) (33 ) — (1,904 ) Net cash (used in) provided by financing activities (243,078 ) 215,063 (2,073 ) 1,184 (28,904 ) Impact of cash on foreign currency — — (471 ) — (471 ) Net decrease in cash (317,738 ) (4,726 ) (11,872 ) 1,184 (333,152 ) Cash — Beginning of period 370,741 10,254 14,933 (12,372 ) 383,556 Cash — End of period $ 53,003 $ 5,528 $ 3,061 $ (11,188 ) $ 50,404

SUMMARY OF ORGANIZATION AND S_2

SUMMARY OF ORGANIZATION AND SIGNIFICANT ACCOUNTING POLICIES - (Policies)	6 Months Ended
	Jun. 29, 2019
Summary Of Significant Accounting Policies And Recent Accounting Pronouncements [Line Items]
Basis of Presentation	Basis of Presentation —These unaudited consolidated financial statements were prepared in accordance with U.S. generally accepted accounting principles (“U.S. GAAP”) for interim financial information, without audit, pursuant to the rules and regulations of the Securities and Exchange Commission (“SEC”). Certain information and footnote disclosures typically included in financial statements prepared in accordance with U.S. GAAP have been condensed or omitted pursuant to such rules and regulations. These unaudited consolidated financial statements should be read in conjunction with the Company's audited consolidated financial statements and the notes thereto as of and for the year ended December 29, 2018 . The Company continues to follow the accounting policies set forth in those audited consolidated financial statements. Management believes that these consolidated interim financial statements include all adjustments, normal and recurring in nature, that are necessary to present fairly the financial position of the Company as of June 29, 2019 , the results of operations for the three and six months ended June 29, 2019 and June 30, 2018 and cash flows for the six months ended June 29, 2019 and June 30, 2018 .
Principles of Consolidation	Principles of Consolidation —The consolidated financial statements include the accounts of Summit Inc. and its majority owned subsidiaries. All intercompany balances and transactions have been eliminated. As a result of the reorganization into a holding company structure (the “Reorganization”), Summit Holdings became a variable interest entity over which Summit Inc. has 100% voting power and control and for which Summit Inc. has the obligation to absorb losses and the right to receive benefits. For a summary of the changes in Summit Inc.’s ownership of Summit Holdings, see Note 9, Stockholders’ Equity.
Use of Estimates	Use of Estimates —Preparation of these consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions. These estimates and the underlying assumptions affect the amounts of assets and liabilities reported, disclosures about contingent assets and liabilities and reported amounts of revenue and expenses. Such estimates include the valuation of accounts receivable, inventories, valuation of deferred tax assets, goodwill, intangibles and other long-lived assets, the tax receivable agreement ("TRA") liability, pension and other postretirement obligations and asset retirement obligations. Estimates also include revenue earned on contracts and costs to complete contracts. Most of the Company’s paving and related services are performed under fixed unit-price contracts with state and local governmental entities. Management regularly evaluates its estimates and assumptions based on historical experience and other factors, including the current economic environment. As future events and their effects cannot be determined with precision, actual results can differ significantly from estimates made. Changes in estimates, including those resulting from continuing changes in the economic environment, are reflected in the Company’s consolidated financial statements when the change in estimate occurs.
Business and Credit Concentrations	Business and Credit Concentrations— The Company’s operations are conducted primarily across 23 U.S. states and in British Columbia, Canada, with the most significant revenue generated in Texas, Utah, Kansas and Missouri. The Company’s accounts receivable consist primarily of amounts due from customers within these areas. Therefore, collection of these accounts is dependent on the economic conditions in the aforementioned states, as well as specific situations affecting individual customers. Credit granted within the Company’s trade areas has been granted to many customers, and management does not believe that a significant concentration of credit exists with respect to any individual customer or group of customers. No single customer accounted for more than 10% of the Company’s total revenue in the three and six months ended June 29, 2019 or June 30, 2018 .
Revenue Recognition	Revenue Recognition —We earn revenue from the sale of products, which primarily include aggregates, cement, ready-mix concrete and asphalt, but also include concrete products and plastics components, and from the provision of services, which are primarily paving and related services, but also include landfill operations, the receipt and disposal of waste that is converted to fuel for use in our cement plants and underground storage space rental. Products We earn revenue from the sale of products, which primarily include aggregates, cement, ready-mix concrete and asphalt, but also include concrete products, net of discounts or allowances, if any, and freight and delivery charges billed to customers. Freight and delivery charges associated with cement sales are recorded on a net basis together with freight costs within cost of sales. Revenue for product sales is recognized when evidence of an arrangement exists and when control passes, which generally is when the product is shipped. Services We earn revenue from the provision of services, which are primarily paving and related services, but also include landfill operations, the receipt and disposal of waste that is converted to fuel for use in our cement plants, and underground storage space rental. Revenue from the receipt of waste fuels is recognized when the waste is accepted and a corresponding liability is recognized for the costs to process the waste into fuel for the manufacturing of cement or to ship the waste offsite for disposal in accordance with applicable regulations. Revenue derived from paving and related services is recognized using the percentage of completion method, which approximates progress towards completion. Under the percentage of completion method, we recognize paving and related services revenue as services are rendered. The majority of our construction service contracts are completed within one year, but may occasionally extend beyond this time frame. We estimate profit as the difference between total estimated revenue and total estimated cost of a contract and recognize that profit over the life of the contract based on input measures. We generally measure progress toward completion on long-term paving and related services contracts based on the proportion of costs incurred to date relative to total estimated costs at completion. We include revisions of estimated profits on contracts in earnings under the cumulative catch-up method, under which the effect of revisions in estimates is recognized immediately. If a revised estimate of contract profitability reveals an anticipated loss on the contract, we recognize the loss in the period it is identified. The percentage of completion method of accounting involves the use of various estimating techniques to project costs at completion, and in some cases includes estimates of recoveries asserted against the customer for changes in specifications or other disputes. Contract estimates involve various assumptions and projections relative to the outcome of future events over multiple periods, including future labor productivity and availability, the nature and complexity of the work to be performed, the cost and availability of materials, the effect of delayed performance, and the availability and timing of funding from the customer. These estimates are based on our best judgment. A significant change in one or more of these estimates could affect the profitability of one or more of our contracts. We review our contract estimates regularly to assess revisions in contract values and estimated costs at completion. Inherent uncertainties in estimating costs make it at least reasonably possible that the estimates used will change within the near term and over the life of the contracts. No material adjustments to a contract were recognized in the three and six months ended June 29, 2019 . Costs and estimated earnings in excess of billings are composed principally of revenue recognized on contracts on the percentage of completion method for which billings had not been presented to customers because the amounts were not billable under the contract terms at the balance sheet date. In accordance with the contract terms, the unbilled receivables at the balance sheet date are expected to be billed in following periods. Billings in excess of costs and estimated earnings represent billings in excess of revenue recognized. Contract assets and liabilities are netted on a contract-by-contract basis.
Earnings per Share	Earnings per Share— The Company computes basic earnings per share attributable to stockholders by dividing income attributable to Summit Inc. by the weighted-average shares of Class A common stock outstanding. Diluted earnings per share reflects the potential dilution beyond shares for basic earnings per share that could occur if securities or other contracts to issue common stock were exercised, converted into common stock, or resulted in the issuance of common stock that would have shared in the Company’s earnings. Since the Class B common stock has no economic value, those shares are not included in the weighted-average common share amount for basic or diluted earnings per share. In addition, as the shares of Class A common stock are issued by Summit Inc., the earnings and equity interests of noncontrolling interests are not included in basic earnings per share.
Tax Receivable Agreement	Tax Receivable Agreement — When Class A limited partnership units of Summit Holdings (“LP Units”) are exchanged for shares of Class A common stock of Summit Inc. or Summit Inc. purchases LP Units for cash, this results in increases in Summit Inc.’s share of the tax basis of the tangible and intangible assets, which increases the tax depreciation and amortization deductions that otherwise would not have been available to Summit Inc. These increases in tax basis and tax depreciation and amortization deductions are expected to reduce the amount of cash taxes that we would otherwise be required to pay in the future. Prior to our initial public offering (“IPO”), we entered into a TRA with the pre-IPO owners that requires us to pay the pre-IPO owners or their permitted assignees 85% of the amount of cash savings, if any, in U.S. federal, state, and local income tax that we actually realize as a result of these exchanges. These benefits include (1) increases in the tax basis of tangible and intangible assets of Summit Holdings and certain other tax benefits related to entering into the TRA, (2) tax benefits attributable to payments under the TRA, or (3) under certain circumstances such as an early termination of the TRA, we are deemed to realize, as a result of the increases in tax basis in connection with exchanges by the pre-IPO owners described above and certain other tax benefits attributable to payments under the TRA. We periodically evaluate the realizability of the deferred tax assets resulting from the exchange of LP Units for Class A common stock. If the deferred tax assets are determined to be realizable, we then assess whether payment of amounts under the TRA have become probable. If so, we record a TRA liability equal to 85% of such deferred tax assets, and the remaining 15% as an increase to additional paid-in capital. If a deferred tax asset subject to the TRA is determined not to be realizable and therefore subject to a valuation allowance, we do not record a TRA liability for such deferred tax assets. In subsequent periods, we assess the realizability of all of our deferred tax assets subject to the TRA. Should we determine a deferred tax asset with a valuation allowance is realizable in a subsequent period, the related valuation allowance will be released and consideration of a corresponding TRA liability will be assessed. The realizability of deferred tax assets, including those subject to the TRA, is dependent upon the generation of future taxable income during the periods in which those deferred tax assets become deductible and consideration of prudent and feasible tax-planning strategies. The measurement of the TRA liability is accounted for as a contingent liability. Therefore, once we determine that a payment to a pre-IPO owner has become probable and can be estimated, the estimate of payment will be accrued.
New Accounting Standards	New Accounting Standards — In February 2016, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) No. 2016-02, Leases (Topic 842), which requires lessees to recognize most leases on the balance sheet. Lessees are required to disclose more quantitative and qualitative information about the leases than current U.S. GAAP requires. The ASU and subsequent amendments issued in 2018 are effective for public entities for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2018. We adopted the standard effective December 30, 2018 using the modified retrospective approach. The modified retrospective approach provides a method for recording existing leases at adoption. In addition, we elected the package of practical expedients permitted under the transition guidance within the new standard, which among other things, allowed us to carry forward the historical lease classification. In addition, we elected the hindsight practical expedient to determine the lease term for existing leases. The most significant impact upon adoption was the recognition of $36.8 million of operating lease right-of-use assets and $36.8 million operating lease liabilities. The standard had no material impact on our statement of cash flows. In August 2017, the FASB issued ASU No. 2017-12, Derivatives and Hedging (Topic 815): Targeted Improvements to Accounting for Hedging Activities, allowing more financial and nonfinancial hedging strategies to be eligible for hedge accounting. The ASU is effective for fiscal years beginning after December 15, 2018 and interim periods within those fiscal years. The adoption of this new ASU did not have a material impact on our consolidated financial results. In June 2018, the FASB issued ASU No. 2018-07, Compensation—Stock Compensation (Topic 718): Improvements to Nonemployee Share-Based Payment Accounting, increasing the scope of Topic 718 to include share-based payment transactions for acquiring goods and services from nonemployees. The ASU is effective for fiscal years beginning after December 15, 2018 and interim periods within those fiscal years. The adoption of this new ASU did not have a material impact on our consolidated financial results.
Leases	We lease construction and office equipment, distribution facilities and office space. Leases with an initial term of 12 months or less, including month to month leases, are not recorded on the balance sheet. Lease expense for short-term leases is recognized on a straight line basis over the lease term. For lease agreements entered into or reassessed after the adoption of ASC 842, we combine lease and nonlease components. While we also own mineral leases for mining operations, those leases are outside the scope of ASC 842. Assets acquired under finance leases are included in property, plant and equipment. We lease construction and office equipment, distribution facilities and office space. Leases with an initial term of 12 months or less, including month to month leases, are not recorded on the balance sheet. Lease expense for short-term leases is recognized on a straight line basis over the lease term. For lease agreements entered into or reassessed after the adoption of ASC 842, we combine lease and nonlease components. While we also own mineral leases for mining operations, those leases are outside the scope of ASC 842. Assets acquired under finance leases are included in property, plant and equipment.
Summit Materials, LLC
Summary Of Significant Accounting Policies And Recent Accounting Pronouncements [Line Items]
Basis of Presentation	Basis of Presentation —These unaudited consolidated financial statements were prepared in accordance with U.S. generally accepted accounting principles (“U.S. GAAP”) for interim financial information, without audit, pursuant to the rules and regulations of the Securities and Exchange Commission (“SEC”). Certain information and footnote disclosures typically included in financial statements prepared in accordance with U.S. GAAP have been condensed or omitted pursuant to such rules and regulations. These unaudited consolidated financial statements should be read in conjunction with the Company’s audited consolidated financial statements and the notes thereto as of and for the year ended December 29, 2018 . The Company continues to follow the accounting policies set forth in those audited consolidated financial statements. Management believes that these consolidated interim financial statements include all adjustments, normal and recurring in nature, that are necessary to present fairly the financial position of the Company as of June 29, 2019 , the results of operations for the three and six months ended June 29, 2019 and June 30, 2018 and cash flows for the six months ended June 29, 2019 and June 30, 2018 .
Use of Estimates	Use of Estimates —Preparation of these consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions. These estimates and the underlying assumptions affect the amounts of assets and liabilities reported, disclosures about contingent assets and liabilities and reported amounts of revenue and expenses. Such estimates include the valuation of accounts receivable, inventories, valuation of deferred tax assets, goodwill, intangibles and other long-lived assets, pension and other postretirement obligations and asset retirement obligations. Estimates also include revenue earned on contracts and costs to complete contracts. Most of the Company’s paving and related services are performed under fixed unit-price contracts with state and local governmental entities. Management regularly evaluates its estimates and assumptions based on historical experience and other factors, including the current economic environment. As future events and their effects cannot be determined with precision, actual results can differ significantly from estimates made. Changes in estimates, including those resulting from continuing changes in the economic environment, are reflected in the Company’s consolidated financial statements when the change in estimate occurs.
Business and Credit Concentrations	Business and Credit Concentrations— The Company’s operations are conducted primarily across 23 U.S. states and in British Columbia, Canada, with the most significant revenue generated in Texas, Utah, Kansas and Missouri. The Company’s accounts receivable consist primarily of amounts due from customers within these areas. Therefore, collection of these accounts is dependent on the economic conditions in the aforementioned states, as well as specific situations affecting individual customers. Credit granted within the Company’s trade areas has been granted to many customers, and management does not believe that a significant concentration of credit exists with respect to any individual customer or group of customers. No single customer accounted for more than 10% of the Company’s total revenue in the three and six months ended June 29, 2019 or June 30, 2018 .
Revenue Recognition	Revenue Recognition —We earn revenue from the sale of products, which primarily include aggregates, cement, ready-mix concrete and asphalt, but also include concrete products and plastics components, and from the provision of services, which are primarily paving and related services, but also include landfill operations, the receipt and disposal of waste that is converted to fuel for use in our cement plants and underground storage space rental. Products We earn revenue from the sale of products, which primarily include aggregates, cement, ready-mix concrete and asphalt, but also include concrete products, net of discounts or allowances, if any, and freight and delivery charges billed to customers. Freight and delivery charges associated with cement sales are recorded on a net basis together with freight costs within cost of sales. Revenue for product sales is recognized when evidence of an arrangement exists and when control passes, which generally is when the product is shipped. Services We earn revenue from the provision of services, which are primarily paving and related services, but also include landfill operations, the receipt and disposal of waste that is converted to fuel for use in our cement plants, and underground storage space rental. Revenue from the receipt of waste fuels is recognized when the waste is accepted and a corresponding liability is recognized for the costs to process the waste into fuel for the manufacturing of cement or to ship the waste offsite for disposal in accordance with applicable regulations. Revenue derived from paving and related services is recognized using the percentage of completion method, which approximates progress towards completion. Under the percentage of completion method, we recognize paving and related services revenue as services are rendered. The majority of our construction service contracts are completed within one year, but may occasionally extend beyond this time frame. We estimate profit as the difference between total estimated revenue and total estimated cost of a contract and recognize that profit over the life of the contract based on input measures. We generally measure progress toward completion on long-term paving and related services contracts based on the proportion of costs incurred to date relative to total estimated costs at completion. We include revisions of estimated profits on contracts in earnings under the cumulative catch-up method, under which the effect of revisions in estimates is recognized immediately. If a revised estimate of contract profitability reveals an anticipated loss on the contract, we recognize the loss in the period it is identified. The percentage of completion method of accounting involves the use of various estimating techniques to project costs at completion, and in some cases includes estimates of recoveries asserted against the customer for changes in specifications or other disputes. Contract estimates involve various assumptions and projections relative to the outcome of future events over multiple periods, including future labor productivity and availability, the nature and complexity of the work to be performed, the cost and availability of materials, the effect of delayed performance, and the availability and timing of funding from the customer. These estimates are based on our best judgment. A significant change in one or more of these estimates could affect the profitability of one or more of our contracts. We review our contract estimates regularly to assess revisions in contract values and estimated costs at completion. Inherent uncertainties in estimating costs make it at least reasonably possible that the estimates used will change within the near term and over the life of the contracts. No material adjustments to a contract were recognized in the three and six months ended June 29, 2019 . Costs and estimated earnings in excess of billings are composed principally of revenue recognized on contracts on the percentage of completion method for which billings had not been presented to customers because the amounts were not billable under the contract terms at the balance sheet date. In accordance with the contract terms, the unbilled receivables at the balance sheet date are expected to be billed in following periods. Billings in excess of costs and estimated earnings represent billings in excess of revenue recognized. Contract assets and liabilities are netted on a contract-by-contract basis.
New Accounting Standards	New Accounting Standards — In February 2016, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) No. 2016-02, Leases (Topic 842), which requires lessees to recognize most leases on the balance sheet. Lessees are required to disclose more quantitative and qualitative information about the leases than current U.S. GAAP requires. The ASU and subsequent amendments issued in 2018 are effective for public entities for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2018. We adopted the standard effective December 30, 2018 using the modified retrospective approach. The modified retrospective approach provides a method for recording existing leases at adoption. In addition, we elected the package of practical expedients permitted under the transition guidance within the new standard, which among other things, allowed us to carry forward the historical lease classification. In addition, we elected the hindsight practical expedient to determine the lease term for existing leases. The most significant impact upon adoption was the recognition of $36.8 million of operating lease right-of-use assets and $36.8 million operating lease liabilities. The standard had no material impact on our statement of cash flows. In August 2017, the FASB issued ASU No. 2017-12, Derivatives and Hedging (Topic 815): Targeted Improvements to Accounting for Hedging Activities, allowing more financial and nonfinancial hedging strategies to be eligible for hedge accounting. The ASU is effective for fiscal years beginning after December 15, 2018 and interim periods within those fiscal years. The adoption of this new ASU did not have a material impact on our consolidated financial results. In June 2018, the FASB issued ASU No. 2018-07, Compensation-Stock Compensation (Topic 718): Improvements to Nonemployee Share-Based Payment Accounting, increasing the scope of Topic 718 to include share-based payment transactions for acquiring goods and services from nonemployees. The ASU is effective for fiscal years beginning after December 15, 2018 and interim periods within those fiscal years. The adoption of this new ASU did not have a material impact on our consolidated financial results.

GOODWILL AND INTANGIBLES - (Tab

GOODWILL AND INTANGIBLES - (Tables)	6 Months Ended
	Jun. 29, 2019
Business Acquisition [Line Items]
Goodwill by Reportable Segment and in Total	Changes in the carrying amount of goodwill, by reportable segment, from December 29, 2018 to June 29, 2019 are summarized as follows: West East Cement Total Balance, December 29, 2018 $ 580,567 $ 406,805 $ 204,656 $ 1,192,028 Acquisitions (1) 1,173 2,621 — 3,794 Foreign currency translation adjustments 2,355 — — 2,355 Balance, June 29, 2019 $ 584,095 $ 409,426 $ 204,656 $ 1,198,177 _____________________________________________________________________________________________ (1) Reflects goodwill from 2019 acquisitions and working capital adjustments from prior year acquisitions.
Intangible Assets by Type and in Total	The following table shows intangible assets by type and in total: June 29, 2019 December 29, 2018 Gross Carrying Amount Accumulated Amortization Net Carrying Amount Gross Carrying Amount Accumulated Amortization Net Carrying Amount Mineral leases $ 19,064 $ (5,835 ) $ 13,229 $ 19,064 $ (5,259 ) $ 13,805 Reserve rights 6,234 (2,098 ) 4,136 6,234 (1,940 ) 4,294 Trade names 1,000 (908 ) 92 1,000 (858 ) 142 Other 409 (213 ) 196 409 (190 ) 219 Total intangible assets $ 26,707 $ (9,054 ) $ 17,653 $ 26,707 $ (8,247 ) $ 18,460
Estimated Amortization Expense for Intangible Assets	he estimated amortization expense for the intangible assets for each of the five years subsequent to June 29, 2019 is as follows: 2019 (six months) $ 791 2020 1,510 2021 1,475 2022 1,482 2023 1,349 2024 1,254 Thereafter 9,792 Total $ 17,653
Summit Materials, LLC
Business Acquisition [Line Items]
Goodwill by Reportable Segment and in Total	Changes in the carrying amount of goodwill, by reportable segment, from December 29, 2018 to June 29, 2019 are summarized as follows: West East Cement Total Balance, December 29, 2018 $ 581,567 $ 406,805 $ 204,656 $ 1,193,028 Acquisitions (1) 1,173 2,621 — 3,794 Foreign currency translation adjustments 2,355 — — 2,355 Balance, June 29, 2019 $ 585,095 $ 409,426 $ 204,656 $ 1,199,177 _______________________________________________________________________ (1) Reflects goodwill from 2019 acquisitions and working capital adjustments from prior year acquisitions.
Intangible Assets by Type and in Total	The following table shows intangible assets by type and in total: June 29, 2019 December 29, 2018 Gross Carrying Amount Accumulated Amortization Net Carrying Amount Gross Carrying Amount Accumulated Amortization Net Carrying Amount Mineral leases $ 19,064 $ (5,835 ) $ 13,229 $ 19,064 $ (5,259 ) $ 13,805 Reserve rights 6,234 (2,098 ) 4,136 6,234 (1,940 ) 4,294 Trade names 1,000 (908 ) 92 1,000 (858 ) 142 Other 409 (213 ) 196 409 (190 ) 219 Total intangible assets $ 26,707 $ (9,054 ) $ 17,653 $ 26,707 $ (8,247 ) $ 18,460
Estimated Amortization Expense for Intangible Assets	The estimated amortization expense for the intangible assets for each of the five years subsequent to June 29, 2019 is as follows: 2019 (six months) $ 791 2020 1,510 2021 1,475 2022 1,482 2023 1,349 2024 1,254 Thereafter 9,792 Total $ 17,653

REVENUE RECOGNITION - (Tables)

REVENUE RECOGNITION - (Tables)	6 Months Ended
	Jun. 29, 2019
Revenue from External Customer [Line Items]
Revenue by Product	Revenue by product for the three and six months ended June 29, 2019 and June 30, 2018 is as follows: Three months ended Six months ended June 29, 2019 June 30, 2018 June 29, 2019 June 30, 2018 Revenue by product*: Aggregates $ 128,650 $ 103,690 $ 216,522 $ 171,140 Cement 77,799 76,413 110,298 109,530 Ready-mix concrete 154,180 160,609 271,500 282,624 Asphalt 93,365 88,372 116,403 106,513 Paving and related services 95,304 107,306 129,649 141,642 Other 51,593 64,500 89,158 103,862 Total revenue $ 600,891 $ 600,890 $ 933,530 $ 915,311 *Revenue from liquid asphalt terminals is included in asphalt revenue.
Schedule of Contract Asset and Liability	The following table outlines the significant changes in contract assets and contract liability balances from December 29, 2018 to June 29, 2019 . Also included in the table is the net change in estimate as a percentage of aggregate revenue for such contracts: Costs and estimated earnings in excess of billings Billings in excess of costs and estimated earnings Balance - December 29, 2018 $ 18,602 $ 11,840 Changes in revenue billed, contract price or cost estimates 26,715 (1,138 ) Other 54 31 Balance - June 29, 2019 $ 45,371 $ 10,733
Summary of Accounts Receivable, Net	Accounts receivable, net consisted of the following as of June 29, 2019 and December 29, 2018 : June 29, 2019 December 29, 2018 Trade accounts receivable $ 232,597 $ 157,601 Construction contract receivables 52,536 47,994 Retention receivables 14,573 15,010 Receivables from related parties 1,198 629 Accounts receivable 300,904 221,234 Less: Allowance for doubtful accounts (6,300 ) (6,716 ) Accounts receivable, net $ 294,604 $ 214,518
Summit Materials, LLC
Revenue from External Customer [Line Items]
Revenue by Product	Revenue by product for the three and six months ended June 29, 2019 and June 30, 2018 is as follows: Three months ended Six months ended June 29, June 30, June 29, June 30, 2019 2018 2019 2018 Revenue by product*: Aggregates $ 128,650 $ 103,690 $ 216,522 $ 171,140 Cement 77,799 76,413 110,298 109,530 Ready-mix concrete 154,180 160,609 271,500 282,624 Asphalt 93,365 88,372 116,403 106,513 Paving and related services 95,304 107,306 129,649 141,642 Other 51,593 64,500 89,158 103,862 Total revenue $ 600,891 $ 600,890 $ 933,530 $ 915,311 *Revenue from liquid asphalt terminals is included in asphalt revenue.
Schedule of Contract Asset and Liability	The following table outlines the significant changes in contract assets and contract liability balances from December 29, 2018 to June 29, 2019 . Also included in the table is the net change in estimate as a percentage of aggregate revenue for such contracts: Costs and estimated Billings in excess earnings in of costs and excess of billings estimated earnings Balance - December 29, 2018 $ 18,602 $ 11,840 Changes in revenue billed, contract price or cost estimates 26,715 (1,138 ) Other 54 31 Balance - June 29, 2019 $ 45,371 $ 10,733
Summary of Accounts Receivable, Net	Accounts receivable, net consisted of the following as of June 29, 2019 and December 29, 2018 : June 29, December 29, 2019 2018 Trade accounts receivable $ 232,597 $ 157,601 Construction contract receivables 52,536 47,994 Retention receivables 14,573 15,010 Receivables from related parties 1,198 629 Accounts receivable 300,904 221,234 Less: Allowance for doubtful accounts (6,300 ) (6,716 ) Accounts receivable, net $ 294,604 $ 214,518

INVENTORIES - (Tables)

INVENTORIES - (Tables)	6 Months Ended
	Jun. 29, 2019
Inventory [Line Items]
Components of Inventories	Inventories consisted of the following as of June 29, 2019 and December 29, 2018 : June 29, 2019 December 29, 2018 Aggregate stockpiles $ 146,264 $ 151,300 Finished goods 29,272 34,993 Work in process 7,754 7,478 Raw materials 24,846 20,080 Total $ 208,136 $ 213,851
Summit Materials, LLC
Inventory [Line Items]
Components of Inventories	Inventories consisted of the following as of June 29, 2019 and December 29, 2018 : June 29, 2019 December 29, 2018 Aggregate stockpiles $ 146,264 $ 151,300 Finished goods 29,272 34,993 Work in process 7,754 7,478 Raw materials 24,846 20,080 Total $ 208,136 $ 213,851

ACCRUED EXPENSES - (Tables)

ACCRUED EXPENSES - (Tables)	6 Months Ended
	Jun. 29, 2019
Schedule Of Accrued Expenses [Line Items]
Components of Accrued Expenses	Accrued expenses consisted of the following as of June 29, 2019 and December 29, 2018 : June 29, 2019 December 29, 2018 Interest $ 25,326 $ 26,223 Payroll and benefits 22,482 15,952 Finance lease obligations 17,805 15,557 Insurance 15,807 13,625 Non-income taxes 13,075 7,442 Professional fees 1,482 1,408 Other (1) 18,019 20,284 Total $ 113,996 $ 100,491 (1) Consists primarily of subcontractor and working capital settlement accruals.
Summit Materials, LLC
Schedule Of Accrued Expenses [Line Items]
Components of Accrued Expenses	Accrued expenses consisted of the following as of June 29, 2019 and December 29, 2018 : June 29, 2019 December 29, 2018 Interest $ 25,326 $ 26,223 Payroll and benefits 22,482 15,952 Finance lease obligations 17,805 15,557 Insurance 15,807 13,625 Non-income taxes 13,307 7,674 Professional fees 1,482 1,408 Other (1) 18,019 19,590 Total $ 114,228 $ 100,029 _______________________________________________________________________ (1) Consists primarily of subcontractor and working capital settlement accruals.

DEBT - (Tables)

DEBT - (Tables)	6 Months Ended
	Jun. 29, 2019
Debt Instrument [Line Items]
Schedule of Debt	Debt consisted of the following as of June 29, 2019 and December 29, 2018 : June 29, 2019 December 29, 2018 Term Loan, due 2024: $625.8 million and $630.6 million, net of $1.2 million and $1.3 million discount at June 29, 2019 and December 29, 2018, respectively $ 624,615 $ 629,268 8 1 ⁄ 2 % Senior Notes, due 2022 — 250,000 6 1 ⁄ 8 % Senior Notes, due 2023: $650.0 million, net of $1.0 million and $1.1 million discount at June 29, 2019 and December 29, 2018, respectively 649,012 648,891 5 1 ⁄ 8 % Senior Notes, due 2025 300,000 300,000 6 1 ⁄ 2 % Senior Notes, due 2027 300,000 — Total 1,873,627 1,828,159 Current portion of long-term debt 4,765 6,354 Long-term debt $ 1,868,862 $ 1,821,805
Schedule of Contractual Payments of Long-Term Debt	The contractual payments of long-term debt, including current maturities, for the five years subsequent to June 29, 2019 , are as follows: 2019 (six months) $ 1,588 2020 7,942 2021 6,354 2022 6,354 2023 656,354 2024 597,252 Thereafter 600,000 Total 1,875,844 Less: Original issue net discount (2,217 ) Less: Capitalized loan costs (14,673 ) Total debt $ 1,858,954
Summary of Activity for Deferred Financing Fees	The following table presents the activity for the deferred financing fees for the six months ended June 29, 2019 and June 30, 2018 : Deferred financing fees Balance—December 29, 2018 $ 15,475 Loan origination fees 6,246 Amortization (1,832 ) Write off of deferred financing fees (2,851 ) Balance—June 29, 2019 $ 17,038 Balance - December 30, 2017 $ 19,033 Loan origination fees 550 Amortization (2,040 ) Balance - June 30, 2018 $ 17,543
Summit Materials, LLC
Debt Instrument [Line Items]
Schedule of Debt	Debt consisted of the following as of June 29, 2019 and December 29, 2018 : June 29, 2019 December 29, 2018 Term Loan, due 2024: $625.8 million and $630.6 million, net of $1.2 million and $1.3 million discount at June 29, 2019 and December 29, 2018, respectively $ 624,615 $ 629,268 8 1/2 % Senior Notes, due 2022 — 250,000 6 1/8 % Senior Notes, due 2023: $650.0 million, net of $1.0 million and $1.1 million discount at June 29, 2019 and December 29, 2018, respectively 649,012 648,891 5 1⁄8 % Senior Notes, due 2025 300,000 300,000 6 1⁄2 % Senior Notes, due 2027 300,000 — Total 1,873,627 1,828,159 Current portion of long-term debt 4,765 6,354 Long-term debt $ 1,868,862 $ 1,821,805
Schedule of Contractual Payments of Long-Term Debt	The contractual payments of long-term debt, including current maturities, for the five years subsequent to June 29, 2019 , are as follows: 2019 (six months) $ 1,588 2020 7,942 2021 6,354 2022 6,354 2023 656,354 2024 597,252 Thereafter 600,000 Total 1,875,844 Less: Original issue net discount (2,217 ) Less: Capitalized loan costs (14,673 ) Total debt $ 1,858,954
Summary of Activity for Deferred Financing Fees	The following table presents the activity for the deferred financing fees for the six months ended June 29, 2019 and June 30, 2018 : Deferred financing fees Balance—December 29, 2018 $ 15,475 Loan origination fees 6,246 Amortization (1,832 ) Write off of deferred financing fees (2,851 ) Balance—June 29, 2019 $ 17,038 Balance - December 30, 2017 $ 19,033 Loan origination fees 550 Amortization (2,040 ) Balance - June 30, 2018 $ 17,543

EARNINGS PER SHARE - (Tables)

EARNINGS PER SHARE - (Tables)	6 Months Ended
	Jun. 29, 2019
Earnings Per Share [Abstract]
Schedule of Basic Earnings Per Share	The following table shows the calculation of basic and diluted loss per share: Three months ended Six months ended June 29, 2019 June 30, 2018 June 29, 2019 June 30, 2018 Net income (loss) attributable to Summit Inc. $ 36,410 $ 35,509 $ (32,362 ) $ (18,220 ) Weighted average shares of Class A stock outstanding 112,070,009 111,564,190 111,940,844 111,111,644 Basic and diluted income (loss) per share $ 0.32 $ 0.32 $ (0.29 ) $ (0.16 ) Diluted net income (loss) attributable to Summit Inc. $ 36,410 $ 35,509 $ (32,362 ) $ (18,220 ) Weighted average shares of Class A stock outstanding 112,070,009 111,564,190 111,940,844 111,111,644 Add: weighted average of LP Units — — — — Add: stock options — 794,065 — — Add: warrants — 36,488 — — Add: restricted stock units 76,539 91,347 — — Add: performance stock units 36,007 97,231 — — Weighted average dilutive shares outstanding 112,182,555 112,583,321 111,940,844 111,111,644 Diluted earnings (loss) per share $ 0.32 $ 0.32 $ (0.29 ) $ (0.16 )
Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share	Excluded from the above calculations were the shares noted below as they were antidilutive: Three months ended Six months ended June 29, 2019 June 30, 2018 June 29, 2019 June 30, 2018 Antidilutive shares: LP Units 3,418,018 3,517,602 3,418,018 3,583,407 Time-vesting stock options 3,168,170 — 3,168,170 3,286,163 Warrants 100,037 — 100,037 100,037 Time-vesting restricted stock units — — 1,493,119 841,618 Market-based restricted stock units — — 390,645 295,252

STOCKHOLDERS' EQUITY_MEMBERS'_2

STOCKHOLDERS' EQUITY/MEMBERS' INTEREST - (Tables)	6 Months Ended
	Jun. 29, 2019
Schedule of Capitalization, Equity [Line Items]
Schedule of changes in ownership of Summit Holdings	The following table summarizes the changes in our ownership of Summit Holdings: Summit Inc. LP Units Total Summit Inc. Balance — December 29, 2018 111,658,927 3,435,518 115,094,445 97.0 % Exchanges during period 17,500 (17,500 ) — Other equity transactions 397,067 — 397,067 Balance — June 29, 2019 112,073,494 3,418,018 115,491,512 97.0 % Balance — December 30, 2017 110,350,594 3,689,620 114,040,214 96.8 % Exchanges during period 229,658 (229,658 ) — Other equity transactions 1,048,986 — 1,048,986 Balance — June 30, 2018 111,629,238 3,459,962 115,089,200 97.0 %
Schedule of Changes in Each Component of Accumulated Other Comprehensive Income (Loss)	The changes in each component of accumulated other comprehensive income (loss) consisted of the following: Change in retirement plans Foreign currency translation adjustments Cash flow hedge adjustments Accumulated other comprehensive income (loss) Balance — December 29, 2018 $ 3,573 $ (2,147 ) $ 1,255 $ 2,681 Foreign currency translation adjustment, net of tax — 3,330 — 3,330 Loss on cash flow hedges, net of tax — — (220 ) (220 ) Balance — June 29, 2019 $ 3,573 $ 1,183 $ 1,035 $ 5,791 Balance — December 30, 2017 $ 2,364 $ 4,637 $ 385 $ 7,386 Foreign currency translation adjustment, net of tax — (3,721 ) — (3,721 ) Income on cash flow hedges, net of tax — — 980 980 Balance — June 30, 2018 $ 2,364 $ 916 $ 1,365 $ 4,645
Summit Materials, LLC
Schedule of Capitalization, Equity [Line Items]
Schedule of Changes in Each Component of Accumulated Other Comprehensive Income (Loss)	The changes in each component of accumulated other comprehensive income (loss) consisted of the following: Accumulated Foreign currency other Change in translation Cash flow hedge comprehensive retirement plans adjustments adjustments (loss) income Balance — December 29, 2018 $ (4,392 ) $ (19,370 ) $ 146 $ (23,616 ) Foreign currency translation adjustment — 4,591 — 4,591 Loss on cash flow hedges — — (303 ) (303 ) Balance — June 29, 2019 $ (4,392 ) $ (14,779 ) $ (157 ) $ (19,328 ) Balance - December 30, 2017 $ (6,053 ) $ (10,022 ) $ (1,060 ) $ (17,135 ) Foreign currency translation adjustment — (5,149 ) — (5,149 ) Income on cash flow hedges — — 1,356 1,356 Balance - June 30, 2018 $ (6,053 ) $ (15,171 ) $ 296 $ (20,928 )

SUPPLEMENTAL CASH FLOW INFORM_2

SUPPLEMENTAL CASH FLOW INFORMATION - (Tables)	6 Months Ended
	Jun. 29, 2019
Schedule Of Cash Flow Supplemental [Line Items]
Schedule of Supplemental Cash Flow Information	Supplemental cash flow information is as follows: Six months ended June 29, 2019 June 30, 2018 Cash payments: Interest $ 36,834 $ 52,206 Income taxes 1,190 3,061 Operating cash payments on operating leases 5,410 — Operating cash payments on finance leases 1,516 — Finance cash payments on finance leases 6,000 — Non cash financing activities: Right of use assets obtained in exchange for operating lease obligations $ 3,298 $ — Right of use assets obtained in exchange for finance leases obligations 16,248 — Exchange of LP Units to shares of Class A common stock 277 6,987
Summit Materials, LLC
Schedule Of Cash Flow Supplemental [Line Items]
Schedule of Supplemental Cash Flow Information	Supplemental cash flow information is as follows: Six months ended June 29, 2019 June 30, 2018 Cash payments: Interest $ 36,834 $ 52,206 Income taxes 1,190 3,061 Operating cash payments on operating leases 5,410 — Operating cash payments on finance leases 1,516 — Finance cash payments on finance leases 6,000 — Non cash financing activities: Right of use assets obtained in exchange for operating lease obligations $ 3,298 $ — Right of use assets obtained in exchange for finance leases obligations 16,248 —

LEASES - (Tables)

LEASES - (Tables)	6 Months Ended
	Jun. 29, 2019
Lessee, Lease, Description [Line Items]
Schedule of Lease Cost	The components of lease expense were as follows: Three months ended Six months ended June 29, 2019 June 29, 2019 Operating lease cost $ 2,694 $ 5,149 Variable lease cost 143 215 Short-term lease cost 9,591 16,172 Financing lease cost: Amortization of right-of-use assets 2,670 5,293 Interest on lease liabilities 876 1,631 Total lease cost $ 15,974 $ 28,460 June 29, 2019 Supplemental balance sheet information related to leases: Operating leases: Operating lease right-of-use assets $ 34,101 Current operating lease liabilities $ 8,470 Noncurrent operating lease liabilities 26,614 Total operating lease liabilities $ 35,084 Finance leases: Property and equipment, gross $ 79,911 Less accumulated depreciation (21,667 ) Property and equipment, net $ 58,244 Current finance lease liabilities $ 17,805 Long-term finance lease liabilities 41,123 Total finance lease liabilities $ 58,928 June 29, 2019 Lease Term Discount Rate (years) (%) Weighted average: Operating leases 7.7 5.6 % Finance lease 2.8 5.5 % Maturities of lease liabilities were as follows: Operating Leases Finance Leases 2019 (six months) $ 5,124 $ 10,115 2020 9,391 17,539 2021 7,434 20,235 2022 4,558 11,745 2023 3,546 1,509 2024 2,413 1,750 Thereafter 11,252 2,662 Total lease payments 43,718 65,555 Less imputed interest (8,634 ) (6,627 ) Present value of lease payments $ 35,084 $ 58,928
Schedule of Lease Assets and Liabilities	The components of lease expense were as follows: Three months ended Six months ended June 29, 2019 June 29, 2019 Operating lease cost $ 2,694 $ 5,149 Variable lease cost 143 215 Short-term lease cost 9,591 16,172 Financing lease cost: Amortization of right-of-use assets 2,670 5,293 Interest on lease liabilities 876 1,631 Total lease cost $ 15,974 $ 28,460 June 29, 2019 Supplemental balance sheet information related to leases: Operating leases: Operating lease right-of-use assets $ 34,101 Current operating lease liabilities $ 8,470 Noncurrent operating lease liabilities 26,614 Total operating lease liabilities $ 35,084 Finance leases: Property and equipment, gross $ 79,911 Less accumulated depreciation (21,667 ) Property and equipment, net $ 58,244 Current finance lease liabilities $ 17,805 Long-term finance lease liabilities 41,123 Total finance lease liabilities $ 58,928 June 29, 2019 Lease Term Discount Rate (years) (%) Weighted average: Operating leases 7.7 5.6 % Finance lease 2.8 5.5 % Maturities of lease liabilities were as follows: Operating Leases Finance Leases 2019 (six months) $ 5,124 $ 10,115 2020 9,391 17,539 2021 7,434 20,235 2022 4,558 11,745 2023 3,546 1,509 2024 2,413 1,750 Thereafter 11,252 2,662 Total lease payments 43,718 65,555 Less imputed interest (8,634 ) (6,627 ) Present value of lease payments $ 35,084 $ 58,928
Schedule of Finance Lease Liability Maturities	The components of lease expense were as follows: Three months ended Six months ended June 29, 2019 June 29, 2019 Operating lease cost $ 2,694 $ 5,149 Variable lease cost 143 215 Short-term lease cost 9,591 16,172 Financing lease cost: Amortization of right-of-use assets 2,670 5,293 Interest on lease liabilities 876 1,631 Total lease cost $ 15,974 $ 28,460 June 29, 2019 Supplemental balance sheet information related to leases: Operating leases: Operating lease right-of-use assets $ 34,101 Current operating lease liabilities $ 8,470 Noncurrent operating lease liabilities 26,614 Total operating lease liabilities $ 35,084 Finance leases: Property and equipment, gross $ 79,911 Less accumulated depreciation (21,667 ) Property and equipment, net $ 58,244 Current finance lease liabilities $ 17,805 Long-term finance lease liabilities 41,123 Total finance lease liabilities $ 58,928 June 29, 2019 Lease Term Discount Rate (years) (%) Weighted average: Operating leases 7.7 5.6 % Finance lease 2.8 5.5 % Maturities of lease liabilities were as follows: Operating Leases Finance Leases 2019 (six months) $ 5,124 $ 10,115 2020 9,391 17,539 2021 7,434 20,235 2022 4,558 11,745 2023 3,546 1,509 2024 2,413 1,750 Thereafter 11,252 2,662 Total lease payments 43,718 65,555 Less imputed interest (8,634 ) (6,627 ) Present value of lease payments $ 35,084 $ 58,928
Schedule of Operating Lease Liability Maturities	The components of lease expense were as follows: Three months ended Six months ended June 29, 2019 June 29, 2019 Operating lease cost $ 2,694 $ 5,149 Variable lease cost 143 215 Short-term lease cost 9,591 16,172 Financing lease cost: Amortization of right-of-use assets 2,670 5,293 Interest on lease liabilities 876 1,631 Total lease cost $ 15,974 $ 28,460 June 29, 2019 Supplemental balance sheet information related to leases: Operating leases: Operating lease right-of-use assets $ 34,101 Current operating lease liabilities $ 8,470 Noncurrent operating lease liabilities 26,614 Total operating lease liabilities $ 35,084 Finance leases: Property and equipment, gross $ 79,911 Less accumulated depreciation (21,667 ) Property and equipment, net $ 58,244 Current finance lease liabilities $ 17,805 Long-term finance lease liabilities 41,123 Total finance lease liabilities $ 58,928 June 29, 2019 Lease Term Discount Rate (years) (%) Weighted average: Operating leases 7.7 5.6 % Finance lease 2.8 5.5 % Maturities of lease liabilities were as follows: Operating Leases Finance Leases 2019 (six months) $ 5,124 $ 10,115 2020 9,391 17,539 2021 7,434 20,235 2022 4,558 11,745 2023 3,546 1,509 2024 2,413 1,750 Thereafter 11,252 2,662 Total lease payments 43,718 65,555 Less imputed interest (8,634 ) (6,627 ) Present value of lease payments $ 35,084 $ 58,928
Schedule of Future Minimum Rental Payments for Operating Leases	As previously disclosed, our future minimum lease payment obligations as of December 29, 2018 were as follows: Operating Leases 2019 $ 9,479 2020 8,101 2021 6,701 2022 4,279 2023 3,411
Summit Materials, LLC
Lessee, Lease, Description [Line Items]
Schedule of Lease Cost	The components of lease expense were as follows: Three months ended Six months ended June 29, 2019 June 29, 2019 Operating lease cost $ 2,694 $ 5,149 Variable lease cost 143 215 Short-term lease cost 9,591 16,172 Financing lease cost: Amortization of right-of-use assets 2,670 5,293 Interest on lease liabilities 876 1,631 Total lease cost $ 15,974 $ 28,460 June 29, 2019 Supplemental balance sheet information related to leases: Operating leases: Operating lease right-of-use assets $ 34,101 Current operating lease liabilities $ 8,470 Noncurrent operating lease liabilities 26,614 Total operating lease liabilities $ 35,084 Finance leases: Property and equipment, gross $ 79,911 Less accumulated depreciation (21,667 ) Property and equipment, net $ 58,244 Current finance lease liabilities $ 17,805 Long-term finance lease liabilities 41,123 Total finance lease liabilities $ 58,928 June 29, 2019 Lease Term Discount Rate (years) (%) Weighted average: Operating leases 7.7 5.6 % Finance lease 2.8 5.5 % Maturities of lease liabilities were as follows: Operating Leases Finance Leases 2019 (six months) $ 5,124 $ 10,115 2020 9,391 17,539 2021 7,434 20,235 2022 4,558 11,745 2023 3,546 1,509 2024 2,413 1,750 Thereafter 11,252 2,662 Total lease payments 43,718 65,555 Less imputed interest (8,634 ) (6,627 ) Present value of lease payments $ 35,084 $ 58,928 As previously disclosed, our future minimum lease payment obligations as of December 29, 2018 were as follows: Operating Leases 2019 $ 9,479 2020 8,101 2021 6,701 2022 4,279 2023 3,411
Schedule of Lease Assets and Liabilities	The components of lease expense were as follows: Three months ended Six months ended June 29, 2019 June 29, 2019 Operating lease cost $ 2,694 $ 5,149 Variable lease cost 143 215 Short-term lease cost 9,591 16,172 Financing lease cost: Amortization of right-of-use assets 2,670 5,293 Interest on lease liabilities 876 1,631 Total lease cost $ 15,974 $ 28,460 June 29, 2019 Supplemental balance sheet information related to leases: Operating leases: Operating lease right-of-use assets $ 34,101 Current operating lease liabilities $ 8,470 Noncurrent operating lease liabilities 26,614 Total operating lease liabilities $ 35,084 Finance leases: Property and equipment, gross $ 79,911 Less accumulated depreciation (21,667 ) Property and equipment, net $ 58,244 Current finance lease liabilities $ 17,805 Long-term finance lease liabilities 41,123 Total finance lease liabilities $ 58,928 June 29, 2019 Lease Term Discount Rate (years) (%) Weighted average: Operating leases 7.7 5.6 % Finance lease 2.8 5.5 % Maturities of lease liabilities were as follows: Operating Leases Finance Leases 2019 (six months) $ 5,124 $ 10,115 2020 9,391 17,539 2021 7,434 20,235 2022 4,558 11,745 2023 3,546 1,509 2024 2,413 1,750 Thereafter 11,252 2,662 Total lease payments 43,718 65,555 Less imputed interest (8,634 ) (6,627 ) Present value of lease payments $ 35,084 $ 58,928
Schedule of Finance Lease Liability Maturities	The components of lease expense were as follows: Three months ended Six months ended June 29, 2019 June 29, 2019 Operating lease cost $ 2,694 $ 5,149 Variable lease cost 143 215 Short-term lease cost 9,591 16,172 Financing lease cost: Amortization of right-of-use assets 2,670 5,293 Interest on lease liabilities 876 1,631 Total lease cost $ 15,974 $ 28,460 June 29, 2019 Supplemental balance sheet information related to leases: Operating leases: Operating lease right-of-use assets $ 34,101 Current operating lease liabilities $ 8,470 Noncurrent operating lease liabilities 26,614 Total operating lease liabilities $ 35,084 Finance leases: Property and equipment, gross $ 79,911 Less accumulated depreciation (21,667 ) Property and equipment, net $ 58,244 Current finance lease liabilities $ 17,805 Long-term finance lease liabilities 41,123 Total finance lease liabilities $ 58,928 June 29, 2019 Lease Term Discount Rate (years) (%) Weighted average: Operating leases 7.7 5.6 % Finance lease 2.8 5.5 % Maturities of lease liabilities were as follows: Operating Leases Finance Leases 2019 (six months) $ 5,124 $ 10,115 2020 9,391 17,539 2021 7,434 20,235 2022 4,558 11,745 2023 3,546 1,509 2024 2,413 1,750 Thereafter 11,252 2,662 Total lease payments 43,718 65,555 Less imputed interest (8,634 ) (6,627 ) Present value of lease payments $ 35,084 $ 58,928
Schedule of Operating Lease Liability Maturities	The components of lease expense were as follows: Three months ended Six months ended June 29, 2019 June 29, 2019 Operating lease cost $ 2,694 $ 5,149 Variable lease cost 143 215 Short-term lease cost 9,591 16,172 Financing lease cost: Amortization of right-of-use assets 2,670 5,293 Interest on lease liabilities 876 1,631 Total lease cost $ 15,974 $ 28,460 June 29, 2019 Supplemental balance sheet information related to leases: Operating leases: Operating lease right-of-use assets $ 34,101 Current operating lease liabilities $ 8,470 Noncurrent operating lease liabilities 26,614 Total operating lease liabilities $ 35,084 Finance leases: Property and equipment, gross $ 79,911 Less accumulated depreciation (21,667 ) Property and equipment, net $ 58,244 Current finance lease liabilities $ 17,805 Long-term finance lease liabilities 41,123 Total finance lease liabilities $ 58,928 June 29, 2019 Lease Term Discount Rate (years) (%) Weighted average: Operating leases 7.7 5.6 % Finance lease 2.8 5.5 % Maturities of lease liabilities were as follows: Operating Leases Finance Leases 2019 (six months) $ 5,124 $ 10,115 2020 9,391 17,539 2021 7,434 20,235 2022 4,558 11,745 2023 3,546 1,509 2024 2,413 1,750 Thereafter 11,252 2,662 Total lease payments 43,718 65,555 Less imputed interest (8,634 ) (6,627 ) Present value of lease payments $ 35,084 $ 58,928

FAIR VALUE - (Tables)

FAIR VALUE - (Tables)	6 Months Ended
	Jun. 29, 2019
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Schedule of Contingent Consideration and Derivatives Measured at Fair Value	The fair value of contingent consideration and derivatives as of June 29, 2019 and December 29, 2018 was: June 29, 2019 December 29, 2018 Current portion of acquisition-related liabilities and Accrued expenses: Contingent consideration $ 2,622 $ 1,394 Cash flow hedges 112 — Acquisition-related liabilities and Other noncurrent liabilities: Contingent consideration $ 1,238 $ 5,175 Cash flow hedges — —
Schedule of Carrying Value and Fair Value of Financial Instruments	The carrying value and fair value of these financial instruments as of June 29, 2019 and December 29, 2018 was: June 29, 2019 December 29, 2018 Fair Value Carrying Value Fair Value Carrying Value Level 2 Long-term debt(1) $ 1,895,932 $ 1,873,627 $ 1,777,722 $ 1,828,159 Level 3 Current portion of deferred consideration and noncompete obligations(2) 32,848 32,848 32,876 32,876 Long term portion of deferred consideration and noncompete obligations(3) 38,850 38,850 44,293 44,293 (1) $4.8 million and $6.4 million were included in current portion of debt as of June 29, 2019 and December 29, 2018 , respectively. (2) Included in current portion of acquisition-related liabilities on the consolidated balance sheets. (3) Included in acquisition-related liabilities on the consolidated balance sheets.
Summit Materials, LLC
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Schedule of Contingent Consideration and Derivatives Measured at Fair Value	The fair value of contingent consideration and derivatives as of June 29, 2019 and December 29, 2018 was: June 29, 2019 December 29, 2018 Current portion of acquisition-related liabilities and Accrued expenses: Contingent consideration $ 2,622 $ 1,394 Cash flow hedges 112 — Acquisition-related liabilities and Other noncurrent liabilities: Contingent consideration $ 1,238 $ 5,175 Cash flow hedges — —
Schedule of Carrying Value and Fair Value of Financial Instruments	The carrying value and fair value of these financial instruments as of June 29, 2019 and December 29, 2018 was: June 29, 2019 December 29, 2018 Fair Value Carrying Value Fair Value Carrying Value Level 2 Long-term debt(1) $ 1,895,932 $ 1,873,627 $ 1,777,722 $ 1,828,159 Level 3 Current portion of deferred consideration and noncompete obligations(2) 30,348 30,348 30,376 30,376 Long term portion of deferred consideration and noncompete obligations(3) 36,951 36,951 40,179 40,179 (1) $4.8 million and $6.4 million were included in current portion of debt as of June 29, 2019 and December 29, 2018 , respectively. (2) Included in current portion of acquisition-related liabilities on the consolidated balance sheets. (3) Included in acquisition-related liabilities on the consolidated balance sheets.

SEGMENT INFORMATION - (Tables)

SEGMENT INFORMATION - (Tables)	6 Months Ended
	Jun. 29, 2019
Segment Reporting Information [Line Items]
Summary of Financial Data for Company's Reportable Business Segments	The following tables display selected financial data for the Company’s reportable business segments as of June 29, 2019 and December 29, 2018 and for the three and six months ended June 29, 2019 and June 30, 2018 : Three months ended Six months ended June 29, 2019 June 30, 2018 June 29, 2019 June 30, 2018 Revenue*: West $ 300,212 $ 321,713 $ 482,157 $ 503,426 East 216,132 197,336 329,520 292,493 Cement 84,547 81,841 121,853 119,392 Total revenue $ 600,891 $ 600,890 $ 933,530 $ 915,311 *Intercompany sales are immaterial and the presentation above only reflects sales to external customers. Three months ended Six months ended June 29, 2019 June 30, 2018 June 29, 2019 June 30, 2018 Income (loss) from operation before taxes $ 54,697 $ 49,103 $ (44,841 ) $ (23,551 ) Interest expense 29,401 28,943 59,506 57,727 Depreciation, depletion and amortization 53,035 49,402 107,842 95,945 Accretion 590 329 1,171 744 Loss on debt financings — 149 14,565 149 Transaction costs 390 1,291 698 2,557 Non-cash compensation 4,699 5,683 10,605 14,190 Other (2,346 ) 441 (2,492 ) (6,907 ) Total Adjusted EBITDA $ 140,466 $ 135,341 $ 147,054 $ 140,854 Total Adjusted EBITDA by Segment: West $ 54,820 $ 61,227 $ 69,118 $ 77,400 East 54,412 45,395 57,654 42,192 Cement 35,441 34,660 32,854 38,327 Corporate and other (4,207 ) (5,941 ) (12,572 ) (17,065 ) Total Adjusted EBITDA $ 140,466 $ 135,341 $ 147,054 $ 140,854 Six months ended June 29, 2019 June 30, 2018 Purchases of property, plant and equipment West $ 51,517 $ 76,223 East 41,801 37,303 Cement 11,467 14,412 Total reportable segments 104,785 127,938 Corporate and other 784 3,719 Total purchases of property, plant and equipment $ 105,569 $ 131,657 Three months ended Six months ended June 29, 2019 June 30, 2018 June 29, 2019 June 30, 2018 Depreciation, depletion, amortization and accretion: West $ 22,924 $ 22,589 $ 46,849 $ 44,740 East 19,840 17,826 40,051 35,553 Cement 9,869 8,681 20,169 15,051 Total reportable segments 52,633 49,096 107,069 95,344 Corporate and other 992 635 1,944 1,345 Total depreciation, depletion, amortization and accretion $ 53,625 $ 49,731 $ 109,013 $ 96,689 June 29, 2019 December 29, 2018 Total assets: West $ 1,437,583 $ 1,370,501 East 1,307,364 1,253,640 Cement 887,751 877,586 Total reportable segments 3,632,698 3,501,727 Corporate and other 322,158 355,914 Total $ 3,954,856 $ 3,857,641
Summit Materials, LLC
Segment Reporting Information [Line Items]
Summary of Financial Data for Company's Reportable Business Segments	The following tables display selected financial data for the Company’s reportable business segments as of June 29, 2019 and December 29, 2018 and for the three and six months ended June 29, 2019 and June 30, 2018 : Three months ended Six months ended June 29, June 30, June 29, June 30, 2019 2018 2019 2018 Revenue*: West $ 300,212 $ 321,713 $ 482,157 $ 503,426 East 216,132 197,336 329,520 292,493 Cement 84,547 81,841 121,853 119,392 Total revenue $ 600,891 $ 600,890 $ 933,530 $ 915,311 *Intercompany sales are immaterial and the presentation above only reflects sales to external customers. Three months ended Six months ended June 29, June 30, June 29, June 30, 2019 2018 2019 2018 Income (loss) from operation before taxes $ 54,815 $ 49,270 $ (44,555 ) $ (23,170 ) Interest expense 29,283 28,776 59,220 57,346 Depreciation, depletion and amortization 53,035 49,402 107,842 95,945 Accretion 590 329 1,171 744 Loss on debt financings — 149 14,565 149 Transaction costs 390 1,291 698 2,557 Non-cash compensation 4,699 5,683 10,605 14,190 Other (2,346 ) 441 (2,492 ) (6,907 ) Total Adjusted EBITDA $ 140,466 $ 135,341 $ 147,054 $ 140,854 Total Adjusted EBITDA by Segment: West $ 54,820 $ 61,227 $ 69,118 $ 77,400 East 54,412 45,395 57,654 42,192 Cement 35,441 34,660 32,854 38,327 Corporate and other (4,207 ) (5,941 ) (12,572 ) (17,065 ) Total Adjusted EBITDA $ 140,466 $ 135,341 $ 147,054 $ 140,854 Six months ended June 29, 2019 June 30, 2018 Purchases of property, plant and equipment West $ 51,517 $ 76,223 East 41,801 37,303 Cement 11,467 14,412 Total reportable segments 104,785 127,938 Corporate and other 784 3,719 Total purchases of property, plant and equipment $ 105,569 $ 131,657 Three months ended Six months ended June 29, June 30, June 29, June 30, 2019 2018 2019 2018 Depreciation, depletion, amortization and accretion: West $ 22,924 $ 22,589 $ 46,849 $ 44,740 East 19,840 17,826 40,051 35,553 Cement 9,869 8,681 20,169 15,051 Total reportable segments 52,633 49,096 107,069 95,344 Corporate and other 992 635 1,944 1,345 Total depreciation, depletion, amortization and accretion $ 53,625 $ 49,731 $ 109,013 $ 96,689 June 29, 2019 December 29, 2018 Total assets: West $ 1,437,583 $ 1,370,501 East 1,307,364 1,253,640 Cement 887,751 877,586 Total reportable segments 3,632,698 3,501,727 Corporate and other 86,069 131,517 Total $ 3,718,767 $ 3,633,244

GUARANTOR AND NON-GUARANTOR F_2

GUARANTOR AND NON-GUARANTOR FINANCIAL INFORMATION - (Tables) - Summit Materials, LLC	6 Months Ended
	Jun. 29, 2019
Condensed Consolidating Balance Sheets	Condensed Consolidating Balance Sheets June 29, 2019 100% Owned Non- Issuers Guarantors Guarantors Eliminations Consolidated Assets Current assets: Cash and cash equivalents $ 69,466 $ 3,712 $ 782 $ (6,302 ) $ 67,658 Accounts receivable, net — 274,291 20,531 (218 ) 294,604 Intercompany receivables 465,120 640,478 — (1,105,598 ) — Cost and estimated earnings in excess of billings — 43,308 2,063 — 45,371 Inventories — 204,291 3,845 — 208,136 Other current assets 1,279 8,025 3,314 — 12,618 Total current assets 535,865 1,174,105 30,535 (1,112,118 ) 628,387 Property, plant and equipment, net 12,008 1,713,138 63,518 — 1,788,664 Goodwill — 1,140,580 58,597 — 1,199,177 Intangible assets, net — 17,653 — — 17,653 Operating lease right-of-use assets 3,653 25,015 5,433 — 34,101 Other assets 3,367,863 158,299 823 (3,476,200 ) 50,785 Total assets $ 3,919,389 $ 4,228,790 $ 158,906 $ (4,588,318 ) $ 3,718,767 Liabilities and Member’s Interest Current liabilities: Current portion of debt $ 4,765 $ — $ — $ — $ 4,765 Current portion of acquisition-related liabilities — 32,970 — — 32,970 Accounts payable 2,367 118,300 11,553 (218 ) 132,002 Accrued expenses 47,231 70,818 2,481 (6,302 ) 114,228 Current operating lease liabilities 735 6,681 1,054 — 8,470 Intercompany payables 642,397 445,051 18,150 (1,105,598 ) — Billings in excess of costs and estimated earnings — 9,897 836 — 10,733 Total current liabilities 697,495 683,717 34,074 (1,112,118 ) 303,168 Long-term debt 1,854,189 — — — 1,854,189 Acquisition-related liabilities — 38,189 — — 38,189 Noncurrent operating lease liabilities 3,867 18,454 4,293 — 26,614 Other noncurrent liabilities 3,794 192,351 77,438 (137,020 ) 136,563 Total liabilities 2,559,345 932,711 115,805 (1,249,138 ) 2,358,723 Total member's interest 1,360,044 3,296,079 43,101 (3,339,180 ) 1,360,044 Total liabilities and member’s interest $ 3,919,389 $ 4,228,790 $ 158,906 $ (4,588,318 ) $ 3,718,767 Condensed Consolidating Balance Sheets December 29, 2018 100% Owned Non- Issuers Guarantors Guarantors Eliminations Consolidated Assets Current assets: Cash and cash equivalents $ 117,219 $ 8,440 $ 7,719 $ (4,870 ) $ 128,508 Accounts receivable, net — 199,538 15,165 (185 ) 214,518 Intercompany receivables 500,765 624,427 — (1,125,192 ) — Cost and estimated earnings in excess of billings — 17,711 891 — 18,602 Inventories — 210,149 3,702 — 213,851 Other current assets 1,953 11,308 2,800 — 16,061 Total current assets 619,937 1,071,573 30,277 (1,130,247 ) 591,540 Property, plant and equipment, net 13,300 1,709,083 57,749 — 1,780,132 Goodwill — 1,136,785 56,243 — 1,193,028 Intangible assets, net — 18,460 — — 18,460 Other assets 3,292,851 154,080 947 (3,397,794 ) 50,084 Total assets $ 3,926,088 $ 4,089,981 $ 145,216 $ (4,528,041 ) $ 3,633,244 Liabilities and Member’s Interest Current liabilities: Current portion of debt $ 6,354 $ — $ — $ — $ 6,354 Current portion of acquisition-related liabilities — 31,770 — — 31,770 Accounts payable 4,712 92,132 12,349 (185 ) 109,008 Accrued expenses 45,146 57,826 1,927 (4,870 ) 100,029 Intercompany payables 673,175 436,564 15,453 (1,125,192 ) — Billings in excess of costs and estimated earnings — 11,347 493 — 11,840 Total current liabilities 729,387 629,639 30,222 (1,130,247 ) 259,001 Long-term debt 1,807,502 — — — 1,807,502 Acquisition-related liabilities — 45,354 — — 45,354 Other noncurrent liabilities 3,768 226,137 77,368 (171,317 ) 135,956 Total liabilities 2,540,657 901,130 107,590 (1,301,564 ) 2,247,813 Total member's interest 1,385,431 3,188,851 37,626 (3,226,477 ) 1,385,431 Total liabilities and member’s interest $ 3,926,088 $ 4,089,981 $ 145,216 $ (4,528,041 ) $ 3,633,244
Condensed Consolidating Statements of Operations and Comprehensive Loss	Condensed Consolidating Statements of Operations For the three months ended June 29, 2019 100% Owned Non- Issuers Guarantors Guarantors Eliminations Consolidated Revenue $ — $ 578,157 $ 25,495 $ (2,761 ) $ 600,891 Cost of revenue (excluding items shown separately below) — 390,640 17,614 (2,761 ) 405,493 General and administrative expenses 9,353 49,288 2,710 — 61,351 Depreciation, depletion, amortization and accretion 992 51,167 1,466 — 53,625 Operating (loss) income (10,345 ) 87,062 3,705 — 80,422 Other income, net (95,320 ) (2,985 ) (372 ) 95,001 (3,676 ) Interest expense (income) 31,022 (2,947 ) 1,208 — 29,283 Income from operation before taxes 53,953 92,994 2,869 (95,001 ) 54,815 Income tax expense 452 85 777 — 1,314 Net income attributable to Summit LLC $ 53,501 $ 92,909 $ 2,092 $ (95,001 ) $ 53,501 Comprehensive income (loss) attributable to member of Summit Materials, LLC $ 55,597 $ 93,046 $ (141 ) $ (92,905 ) $ 55,597 Condensed Consolidating Statements of Operations For the six months ended June 29, 2019 100% Owned Non- Issuers Guarantors Guarantors Eliminations Consolidated Revenue $ — $ 896,338 $ 41,136 $ (3,944 ) $ 933,530 Cost of revenue (excluding items shown separately below) — 646,807 29,634 (3,944 ) 672,497 General and administrative expenses 24,284 99,319 5,666 — 129,269 Depreciation, depletion, amortization and accretion 1,945 104,087 2,981 — 109,013 Operating (loss) income (26,229 ) 46,125 2,855 — 22,751 Other (income) loss, net (51,710 ) (4,926 ) (775 ) 65,497 8,086 Interest expense (income) 62,718 (5,911 ) 2,413 — 59,220 (Loss) income from operation before taxes (37,237 ) 56,962 1,217 (65,497 ) (44,555 ) Income tax expense (benefit) 826 (7,652 ) 334 — (6,492 ) Net (loss) income attributable to Summit LLC $ (38,063 ) $ 64,614 $ 883 $ (65,497 ) $ (38,063 ) Comprehensive (loss) income attributable to member of Summit Materials, LLC $ (33,775 ) $ 64,917 $ (3,708 ) $ (61,209 ) $ (33,775 ) Condensed Consolidating Statements of Operations For the three months ended June 30, 2018 100% Owned Non- Issuers Guarantors Guarantors Eliminations Consolidated Revenue $ — $ 580,157 $ 22,352 $ (1,619 ) $ 600,890 Cost of revenue (excluding items shown separately below) — 396,629 15,922 (1,619 ) 410,932 General and administrative expenses 13,276 47,287 2,385 — 62,948 Depreciation, depletion, amortization and accretion 635 47,929 1,167 — 49,731 Operating (loss) income (13,911 ) 88,312 2,878 — 77,279 Other (income) loss, net (89,659 ) (687 ) 98 89,481 (767 ) Interest expense (income) 28,946 (1,362 ) 1,192 — 28,776 Income from operation before taxes 46,802 90,361 1,588 (89,481 ) 49,270 Income tax expense 200 2,036 432 — 2,668 Net income attributable to Summit LLC $ 46,602 $ 88,325 $ 1,156 $ (89,481 ) $ 46,602 Comprehensive income attributable to member of Summit Materials, LLC $ 44,918 $ 87,964 $ 3,201 $ (91,165 ) $ 44,918 Condensed Consolidating Statements of Operations For the six months ended June 30, 2018 100% Owned Non- Issuers Guarantors Guarantors Eliminations Consolidated Revenue $ — $ 880,815 $ 37,533 $ (3,037 ) $ 915,311 Cost of revenue (excluding items shown separately below) — 634,756 27,074 (3,037 ) 658,793 General and administrative expenses 34,224 94,463 5,388 — 134,075 Depreciation, depletion, amortization and accretion 1,345 92,922 2,422 — 96,689 Operating (loss) income (35,569 ) 58,674 2,649 — 25,754 Other (income) loss, net (72,294 ) (7,544 ) 149 71,267 (8,422 ) Interest expense (income) 58,527 (3,565 ) 2,384 — 57,346 (Loss) income from operation before taxes (21,802 ) 69,783 116 (71,267 ) (23,170 ) Income tax expense (benefit) 192 (1,417 ) 49 — (1,176 ) Net (loss) income attributable to Summit LLC $ (21,994 ) $ 71,200 $ 67 $ (71,267 ) $ (21,994 ) Comprehensive (loss) income attributable to member of Summit Materials, LLC $ (25,787 ) $ 69,844 $ 5,216 $ (75,060 ) $ (25,787 )
Condensed Consolidating Statements of Cash Flows	Condensed Consolidating Statements of Cash Flows For the six months ended June 29, 2019 100% Owned Non- Issuers Guarantors Guarantors Eliminations Consolidated Net cash (used in) provided by operating activities $ (43,760 ) $ 59,190 $ 518 $ — $ 15,948 Cash flow from investing activities: Acquisitions, net of cash acquired — (2,842 ) — — (2,842 ) Purchase of property, plant and equipment (785 ) (96,883 ) (7,901 ) — (105,569 ) Proceeds from the sale of property, plant, and equipment — 7,940 65 — 8,005 Other — (439 ) — — (439 ) Net cash used for investing activities (785 ) (92,224 ) (7,836 ) — (100,845 ) Cash flow from financing activities: Proceeds from investment by member (36,356 ) 37,140 — — 784 Net proceeds from debt issuance 300,000 — — — 300,000 Loans received from and payments made on loans from other Summit Companies (2,879 ) 3,997 314 (1,432 ) — Payments on long-term debt (254,765 ) (6,133 ) (127 ) — (261,025 ) Payments on acquisition-related liabilities — (6,658 ) — — (6,658 ) Debt issuance costs (6,246 ) — — — (6,246 ) Distributions from partnership (2,500 ) — — — (2,500 ) Other (462 ) (40 ) — — (502 ) Net cash (used in) provided by financing activities (3,208 ) 28,306 187 (1,432 ) 23,853 Impact of cash on foreign currency — — 194 — 194 Net decrease in cash (47,753 ) (4,728 ) (6,937 ) (1,432 ) (60,850 ) Cash — Beginning of period 117,219 8,440 7,719 (4,870 ) 128,508 Cash — End of period $ 69,466 $ 3,712 $ 782 $ (6,302 ) $ 67,658 Condensed Consolidating Statements of Cash Flows For the six months ended June 30, 2018 100% Owned Non- Issuers Guarantors Guarantors Eliminations Consolidated Net cash (used in) provided by operating activities $ (70,942 ) $ 34,740 $ 2,484 $ — $ (33,718 ) Cash flow from investing activities: Acquisitions, net of cash acquired — (153,196 ) — — (153,196 ) Purchase of property, plant and equipment (3,718 ) (115,967 ) (11,972 ) — (131,657 ) Proceeds from the sale of property, plant, and equipment — 13,950 160 — 14,110 Other — 684 — — 684 Net cash used for investing activities (3,718 ) (254,529 ) (11,812 ) — (270,059 ) Cash flow from financing activities: Proceeds from investment by member (100,271 ) 115,886 — — 15,615 Loans received from and payments made on loans from other Summit Companies (135,634 ) 136,483 (2,033 ) 1,184 — Payments on long-term debt (3,178 ) (7,587 ) (7 ) — (10,772 ) Payments on acquisition-related liabilities — (28,724 ) — — (28,724 ) Financing costs (550 ) — — — (550 ) Distributions from partnership (2,569 ) — — — (2,569 ) Other (876 ) (995 ) (33 ) — (1,904 ) Net cash (used in) provided by financing activities (243,078 ) 215,063 (2,073 ) 1,184 (28,904 ) Impact of cash on foreign currency — — (471 ) — (471 ) Net decrease in cash (317,738 ) (4,726 ) (11,872 ) 1,184 (333,152 ) Cash — Beginning of period 370,741 10,254 14,933 (12,372 ) 383,556 Cash — End of period $ 53,003 $ 5,528 $ 3,061 $ (11,188 ) $ 50,404

SUMMARY OF ORGANIZATION AND S_3

SUMMARY OF ORGANIZATION AND SIGNIFICANT ACCOUNTING POLICIES - General Information (Details)	6 Months Ended
	Jun. 29, 2019segmentplant
Summary Of Significant Accounting Policies And Recent Accounting Pronouncements [Line Items]
Number of operating segments	3
Number of reportable segments	3
Cement plant
Summary Of Significant Accounting Policies And Recent Accounting Pronouncements [Line Items]
Number of plants | plant	2
Summit Materials, LLC
Summary Of Significant Accounting Policies And Recent Accounting Pronouncements [Line Items]
Number of operating segments	3
Number of reportable segments	3
Summit Materials, LLC | Cement plant
Summary Of Significant Accounting Policies And Recent Accounting Pronouncements [Line Items]
Number of plants | plant	2
Summit Holdings LP
Summary Of Significant Accounting Policies And Recent Accounting Pronouncements [Line Items]
Voting power (as a percent)	100.00%

SUMMARY OF ORGANIZATION AND S_4

SUMMARY OF ORGANIZATION AND SIGNIFICANT ACCOUNTING POLICIES - Business and Credit Concentration (Details)	6 Months Ended
	Jun. 29, 2019state
Summit Materials, LLC
Business and Credit Concentrations
Number of states in which the entity operates	23
Tax Receivable Agreement | Summit Holdings LP
Business and Credit Concentrations
Percentage of benefits to be paid on tax receivable agreement	85.00%
Percentage of the tax receivable agreement allocated to additional paid-in capital	15.00%

SUMMARY OF ORGANIZATION AND S_5

SUMMARY OF ORGANIZATION AND SIGNIFICANT ACCOUNTING POLICIES - New Accounting Standards (Details) - USD ($) $ in Thousands	Jun. 29, 2019	Dec. 30, 2018
Summary Of Significant Accounting Policies And Recent Accounting Pronouncements [Line Items]
Operating lease right-of-use assets	$ 34,101	$ 36,800
Operating lease liability	35,084	36,800
Summit Materials, LLC
Summary Of Significant Accounting Policies And Recent Accounting Pronouncements [Line Items]
Operating lease right-of-use assets	34,101	36,800
Operating lease liability	$ 35,084	$ 36,800

GOODWILL AND INTANGIBLES - Summ

GOODWILL AND INTANGIBLES - Summary of Goodwill by Reportable Segments (Details) $ in Thousands	6 Months Ended
	Jun. 29, 2019USD ($)
Goodwill [Roll Forward]
Balance, December 29, 2018	$ 1,192,028
Acquisitions	3,794
Foreign currency translation adjustments	2,355
Balance, June 29, 2019	1,198,177
West
Goodwill [Roll Forward]
Balance, December 29, 2018	580,567
Acquisitions	1,173
Foreign currency translation adjustments	2,355
Balance, June 29, 2019	584,095
East
Goodwill [Roll Forward]
Balance, December 29, 2018	406,805
Acquisitions	2,621
Foreign currency translation adjustments	0
Balance, June 29, 2019	409,426
Cement
Goodwill [Roll Forward]
Balance, December 29, 2018	204,656
Acquisitions	0
Foreign currency translation adjustments	0
Balance, June 29, 2019	204,656
Summit Materials, LLC
Goodwill [Roll Forward]
Balance, December 29, 2018	1,193,028
Acquisitions	3,794
Foreign currency translation adjustments	2,355
Balance, June 29, 2019	1,199,177
Summit Materials, LLC | West
Goodwill [Roll Forward]
Balance, December 29, 2018	581,567
Acquisitions	1,173
Foreign currency translation adjustments	2,355
Balance, June 29, 2019	585,095
Summit Materials, LLC | East
Goodwill [Roll Forward]
Balance, December 29, 2018	406,805
Acquisitions	2,621
Foreign currency translation adjustments	0
Balance, June 29, 2019	409,426
Summit Materials, LLC | Cement
Goodwill [Roll Forward]
Balance, December 29, 2018	204,656
Acquisitions	0
Foreign currency translation adjustments	0
Balance, June 29, 2019	$ 204,656

GOODWILL AND INTANGIBLES - Inta

GOODWILL AND INTANGIBLES - Intangible Assets By Type (Details) - USD ($) $ in Thousands	Jun. 29, 2019	Dec. 29, 2018
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 26,707	$ 26,707
Accumulated Amortization	(9,054)	(8,247)
Net Carrying Amount	17,653	18,460
Mineral leases
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	19,064	19,064
Accumulated Amortization	(5,835)	(5,259)
Net Carrying Amount	13,229	13,805
Reserve rights
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	6,234	6,234
Accumulated Amortization	(2,098)	(1,940)
Net Carrying Amount	4,136	4,294
Trade names
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	1,000	1,000
Accumulated Amortization	(908)	(858)
Net Carrying Amount	92	142
Other
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	409	409
Accumulated Amortization	(213)	(190)
Net Carrying Amount	196	219
Summit Materials, LLC
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	26,707	26,707
Accumulated Amortization	(9,054)	(8,247)
Net Carrying Amount	17,653	18,460
Summit Materials, LLC | Mineral leases
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	19,064	19,064
Accumulated Amortization	(5,835)	(5,259)
Net Carrying Amount	13,229	13,805
Summit Materials, LLC | Reserve rights
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	6,234	6,234
Accumulated Amortization	(2,098)	(1,940)
Net Carrying Amount	4,136	4,294
Summit Materials, LLC | Trade names
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	1,000	1,000
Accumulated Amortization	(908)	(858)
Net Carrying Amount	92	142
Summit Materials, LLC | Other
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	409	409
Accumulated Amortization	(213)	(190)
Net Carrying Amount	$ 196	$ 219

GOODWILL AND INTANGIBLES - Amor

GOODWILL AND INTANGIBLES - Amortization Expense (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 29, 2019	Jun. 30, 2018	Jun. 29, 2019	Jun. 30, 2018	Dec. 29, 2018
Business Acquisition [Line Items]
Amortization expense	$ 400	$ 300	$ 800	$ 600
Estimated amortization expense
2019 (six months)	791		791
2020	1,510		1,510
2021	1,475		1,475
2022	1,482		1,482
2023	1,349		1,349
2024	1,254		1,254
Thereafter	9,792		9,792
Total	17,653		17,653		$ 18,460
Summit Materials, LLC
Business Acquisition [Line Items]
Amortization expense	400	$ 300	800	$ 600
Estimated amortization expense
2019 (six months)	791		791
2020	1,510		1,510
2021	1,475		1,475
2022	1,482		1,482
2023	1,349		1,349
2024	1,254		1,254
Thereafter	9,792		9,792
Total	$ 17,653		$ 17,653		$ 18,460

REVENUE RECOGNITION - By Produc

REVENUE RECOGNITION - By Product (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 29, 2019	Jun. 30, 2018	Jun. 29, 2019	Jun. 30, 2018
Revenue from External Customer [Line Items]
Total revenue	$ 600,891	$ 600,890	$ 933,530	$ 915,311
Aggregates
Revenue from External Customer [Line Items]
Total revenue	128,650	103,690	216,522	171,140
Cement
Revenue from External Customer [Line Items]
Total revenue	77,799	76,413	110,298	109,530
Ready-mix concrete
Revenue from External Customer [Line Items]
Total revenue	154,180	160,609	271,500	282,624
Asphalt
Revenue from External Customer [Line Items]
Total revenue	93,365	88,372	116,403	106,513
Paving and related services
Revenue from External Customer [Line Items]
Total revenue	95,304	107,306	129,649	141,642
Other
Revenue from External Customer [Line Items]
Total revenue	51,593	64,500	89,158	103,862
Summit Materials, LLC
Revenue from External Customer [Line Items]
Total revenue	600,891	600,890	933,530	915,311
Summit Materials, LLC | Aggregates
Revenue from External Customer [Line Items]
Total revenue	128,650	103,690	216,522	171,140
Summit Materials, LLC | Cement
Revenue from External Customer [Line Items]
Total revenue	77,799	76,413	110,298	109,530
Summit Materials, LLC | Ready-mix concrete
Revenue from External Customer [Line Items]
Total revenue	154,180	160,609	271,500	282,624
Summit Materials, LLC | Asphalt
Revenue from External Customer [Line Items]
Total revenue	93,365	88,372	116,403	106,513
Summit Materials, LLC | Paving and related services
Revenue from External Customer [Line Items]
Total revenue	95,304	107,306	129,649	141,642
Summit Materials, LLC | Other
Revenue from External Customer [Line Items]
Total revenue	$ 51,593	$ 64,500	$ 89,158	$ 103,862

REVENUE RECOGNITION - Contract

REVENUE RECOGNITION - Contract Assets and Liabilities (Details) $ in Thousands	6 Months Ended
	Jun. 29, 2019USD ($)
Change in Contract with Customer, Asset [Abstract]
Beginning balance	$ 18,602
Changes in revenue billed, contract price or cost estimates	26,715
Other	54
Ending balance	45,371
Change in Contract with Customer, Liability [Abstract]
Beginning balance	11,840
Changes in revenue billed, contract price or cost estimates	(1,138)
Other	31
Ending balance	10,733
Summit Materials, LLC
Change in Contract with Customer, Asset [Abstract]
Beginning balance	18,602
Changes in revenue billed, contract price or cost estimates	26,715
Other	54
Ending balance	45,371
Change in Contract with Customer, Liability [Abstract]
Beginning balance	11,840
Changes in revenue billed, contract price or cost estimates	(1,138)
Other	31
Ending balance	$ 10,733

REVENUE RECOGNITION - Summary o

REVENUE RECOGNITION - Summary of Accounts Receivable, Net (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 29, 2019	Dec. 29, 2018
Accounts, Notes, Loans and Financing Receivable [Line Items]
Trade accounts receivable	$ 232,597	$ 157,601
Construction contract receivables	52,536	47,994
Retention receivables	14,573	15,010
Receivables from related parties	1,198	629
Accounts receivable	300,904	221,234
Less: Allowance for doubtful accounts	(6,300)	(6,716)
Accounts receivable, net	$ 294,604	214,518
Maximum
Accounts, Notes, Loans and Financing Receivable [Line Items]
General collection and billing period for retention receivables	1 year
Summit Materials, LLC
Accounts, Notes, Loans and Financing Receivable [Line Items]
Trade accounts receivable	$ 232,597	157,601
Construction contract receivables	52,536	47,994
Retention receivables	14,573	15,010
Receivables from related parties	1,198	629
Accounts receivable	300,904	221,234
Less: Allowance for doubtful accounts	(6,300)	(6,716)
Accounts receivable, net	$ 294,604	$ 214,518
Summit Materials, LLC | Maximum
Accounts, Notes, Loans and Financing Receivable [Line Items]
General collection and billing period for retention receivables	1 year

INVENTORIES - Components of Inv

INVENTORIES - Components of Inventories (Details) - USD ($) $ in Thousands	Jun. 29, 2019	Dec. 29, 2018
Inventory [Line Items]
Aggregate stockpiles	$ 146,264	$ 151,300
Finished goods	29,272	34,993
Work in process	7,754	7,478
Raw materials	24,846	20,080
Total	208,136	213,851
Summit Materials, LLC
Inventory [Line Items]
Aggregate stockpiles	146,264	151,300
Finished goods	29,272	34,993
Work in process	7,754	7,478
Raw materials	24,846	20,080
Total	$ 208,136	$ 213,851

ACCRUED EXPENSES - Components o

ACCRUED EXPENSES - Components of Accrued Expenses (Details) - USD ($) $ in Thousands	Jun. 29, 2019	Dec. 29, 2018
Schedule Of Accrued Expenses [Line Items]
Interest	$ 25,326	$ 26,223
Payroll and benefits	22,482	15,952
Finance lease obligations	17,805
Finance lease obligations		15,557
Insurance	15,807	13,625
Non-income taxes	13,075	7,442
Professional fees	1,482	1,408
Other	18,019	20,284
Total	113,996	100,491
Summit Materials, LLC
Schedule Of Accrued Expenses [Line Items]
Interest	25,326	26,223
Payroll and benefits	22,482	15,952
Finance lease obligations	17,805
Finance lease obligations		15,557
Insurance	15,807	13,625
Non-income taxes	13,307	7,674
Professional fees	1,482	1,408
Other	18,019	19,590
Total	$ 114,228	$ 100,029

DEBT - Schedule of Debt (Detail

DEBT - Schedule of Debt (Details) - USD ($) $ in Thousands	Jun. 29, 2019	Mar. 30, 2019	Mar. 15, 2019	Dec. 29, 2018	Jun. 01, 2017	Jul. 08, 2015
Debt Instrument [Line Items]
Total debt	$ 1,873,627			$ 1,828,159
Current portion of long-term debt	4,765			6,354
Long-term debt	1,868,862			1,821,805
Gross amount	1,875,844
Debt discount	2,217
Term Loan, due 2024
Debt Instrument [Line Items]
Total debt	624,615			629,268
Gross amount	625,800			630,600
Debt discount	1,200			1,300
8 1/2% Senior Notes, due 2022
Debt Instrument [Line Items]
Total debt	0			$ 250,000
Debt instrument interest rate (as a percent)				8.50%
6 1/8% Senior Notes, due 2023
Debt Instrument [Line Items]
Total debt	649,012			$ 648,891
Gross amount	650,000			650,000
Debt discount	$ 1,000			1,100
Debt instrument interest rate (as a percent)	6.125%
5 1/8% Senior Notes, due 2025
Debt Instrument [Line Items]
Total debt	$ 300,000			300,000
Debt instrument interest rate (as a percent)	5.125%
Summit Materials, LLC
Debt Instrument [Line Items]
Total debt	$ 1,873,627			1,828,159
Current portion of long-term debt	4,765			6,354
Gross amount	1,875,844
Debt discount	2,217
Summit Materials, LLC | Term Loan, due 2024
Debt Instrument [Line Items]
Total debt	624,615			629,268
Gross amount	625,800			630,600
Debt discount	1,200			1,300
Summit Materials, LLC | 8 1/2% Senior Notes, due 2022
Debt Instrument [Line Items]
Total debt	0			$ 250,000
Debt instrument interest rate (as a percent)		8.50%		8.50%
Summit Materials, LLC | 6 1/8% Senior Notes, due 2023
Debt Instrument [Line Items]
Total debt	649,012			$ 648,891
Gross amount	650,000			650,000
Debt discount	$ 1,000			1,100
Debt instrument interest rate (as a percent)	6.125%					6.125%
Summit Materials, LLC | 5 1/8% Senior Notes, due 2025
Debt Instrument [Line Items]
Total debt	$ 300,000			300,000	$ 300,000
Debt instrument interest rate (as a percent)	5.125%				5.125%
Summit Materials, LLC | 6 1/2% Senior Notes, due 2027
Debt Instrument [Line Items]
Debt instrument interest rate (as a percent)	6.50%
Senior Notes | 6 1/2% Senior Notes, due 2027
Debt Instrument [Line Items]
Total debt	$ 300,000			0
Debt instrument interest rate (as a percent)	6.50%
Senior Notes | Summit Materials, LLC | 6 1/2% Senior Notes, due 2027
Debt Instrument [Line Items]
Total debt	$ 300,000		$ 300,000	$ 0
Debt instrument interest rate (as a percent)			6.50%

DEBT - Schedule of Contractual

DEBT - Schedule of Contractual Payments of Long-Term Debt (Details) $ in Thousands	Jun. 29, 2019USD ($)
Debt Instrument [Line Items]
2019 (six months)	$ 1,588
2020	7,942
2021	6,354
2022	6,354
2023	656,354
2024	597,252
Thereafter	600,000
Total	1,875,844
Less: Original issue net discount	(2,217)
Less: Capitalized loan costs	(14,673)
Total debt	1,858,954
Summit Materials, LLC
Debt Instrument [Line Items]
2019 (six months)	1,588
2020	7,942
2021	6,354
2022	6,354
2023	656,354
2024	597,252
Thereafter	600,000
Total	1,875,844
Less: Original issue net discount	(2,217)
Less: Capitalized loan costs	(14,673)
Total debt	$ 1,858,954

DEBT - Senior Notes (Details)

DEBT - Senior Notes (Details) - USD ($)	Mar. 15, 2019	Jun. 01, 2017	Jul. 08, 2015	Mar. 30, 2019	Jun. 29, 2019	Dec. 29, 2018
Debt Instrument [Line Items]
Long-term debt					$ 1,873,627,000	$ 1,828,159,000
Write off of deferred financing fees					2,851,000
8 1/2% Senior Notes, due 2022
Debt Instrument [Line Items]
Long-term debt					0	$ 250,000,000
Senior notes, interest rate (as a percent)						8.50%
5 1/8% Senior Notes, due 2025
Debt Instrument [Line Items]
Long-term debt					$ 300,000,000	$ 300,000,000
Senior notes, interest rate (as a percent)					5.125%
6 1/8% Senior Notes, due 2023
Debt Instrument [Line Items]
Long-term debt					$ 649,012,000	648,891,000
Senior notes, interest rate (as a percent)					6.125%
Issuers | 8 1/2% Senior Notes, due 2022
Debt Instrument [Line Items]
Senior notes, interest rate (as a percent)				8.50%
Debt instrument, repurchased face amount				$ 250,000,000
Debt instrument redemption charge				14,600,000
Debt instrument, prepayment premium				11,700,000
Write off of deferred financing fees				2,900,000
Issuers | 5 1/8% Senior Notes, due 2025
Debt Instrument [Line Items]
Long-term debt		$ 300,000,000
Senior notes, interest rate (as a percent)		5.125%
Percentage of par value of senior notes		100.00%
Proceeds net of related fees and expenses		$ 295,400,000
Issuers | 6 1/8% Senior Notes, due 2023
Debt Instrument [Line Items]
Senior notes, interest rate (as a percent)			6.125%
Debt instrument, face amount			$ 650,000,000
Issuers | 6 1/8% Senior Notes, due 2023, issued at par
Debt Instrument [Line Items]
Debt instrument, face amount			$ 350,000,000
Issuers | 6 1/8% Senior Notes, due 2023, issued at 99.375% of par
Debt Instrument [Line Items]
Percentage of par value of senior notes			99.375%
Debt instrument, face amount			$ 300,000,000
Summit Materials, LLC
Debt Instrument [Line Items]
Long-term debt					$ 1,873,627,000	1,828,159,000
Write off of deferred financing fees					$ 2,851,000
Summit Materials, LLC | 6 1/2% Senior Notes, due 2027
Debt Instrument [Line Items]
Senior notes, interest rate (as a percent)					6.50%
Debt instrument redemption charge				$ 14,600,000
Summit Materials, LLC | 8 1/2% Senior Notes, due 2022
Debt Instrument [Line Items]
Long-term debt					$ 0	$ 250,000,000
Senior notes, interest rate (as a percent)				8.50%		8.50%
Debt instrument, repurchased face amount				$ 250,000,000
Debt instrument, prepayment premium				11,700,000
Write off of deferred financing fees				$ 2,900,000
Summit Materials, LLC | 5 1/8% Senior Notes, due 2025
Debt Instrument [Line Items]
Long-term debt		$ 300,000,000			$ 300,000,000	$ 300,000,000
Senior notes, interest rate (as a percent)		5.125%			5.125%
Summit Materials, LLC | 6 1/8% Senior Notes, due 2023
Debt Instrument [Line Items]
Long-term debt					$ 649,012,000	648,891,000
Senior notes, interest rate (as a percent)			6.125%		6.125%
Debt instrument, face amount			$ 650,000,000
Senior Notes | 6 1/2% Senior Notes, due 2027
Debt Instrument [Line Items]
Long-term debt					$ 300,000,000	0
Senior notes, interest rate (as a percent)					6.50%
Senior Notes | Issuers | 6 1/2% Senior Notes, due 2027
Debt Instrument [Line Items]
Long-term debt	$ 300,000,000
Senior notes, interest rate (as a percent)	6.50%
Percentage of par value of senior notes	100.00%
Proceeds net of related fees and expenses	$ 296,300,000
Senior Notes | Summit Materials, LLC | 6 1/2% Senior Notes, due 2027
Debt Instrument [Line Items]
Long-term debt	$ 300,000,000				$ 300,000,000	$ 0
Senior notes, interest rate (as a percent)	6.50%
Percentage of par value of senior notes	100.00%
Proceeds net of related fees and expenses	$ 296,300,000

DEBT - Senior Secured Credit Fa

DEBT - Senior Secured Credit Facilities (Details) - Summit Materials, LLC - USD ($)	Feb. 25, 2019	Jun. 29, 2019	Dec. 29, 2018
Term Loan, due 2024
Debt Instrument [Line Items]
Debt instrument, face amount		$ 650,000,000
Quarterly principal repayments percentage		0.25%
Revolving Credit Facility
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 345,000,000	$ 345,000,000
Amount outstanding		0	$ 0
Remaining borrowing capacity		329,800,000
Revolving Credit Facility | Federal funds rate
Debt Instrument [Line Items]
Basis spread on variable rate	0.50%
Revolving Credit Facility | LIBOR Plus 1%
Debt Instrument [Line Items]
Basis spread on variable rate	2.00%
Percentage added to base rate	1.00%
Revolving Credit Facility | LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate	3.00%
Letter of Credit
Debt Instrument [Line Items]
Amount outstanding		$ 15,200,000
Senior Secured Credit Facilities
Debt Instrument [Line Items]
First lien leverage ratio	0.0475

DEBT - Summary of Activity for

DEBT - Summary of Activity for Deferred Financing Fees (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 29, 2019	Jun. 30, 2018
Deferred Finance Costs, Own-share Lending Arrangement, Issuance Costs, Accumulated Amortization [Roll Forward]
Beginning balance	$ 15,475	$ 19,033
Loan origination fees	6,246	550
Amortization	(1,832)	(2,040)
Write off of deferred financing fees	(2,851)
Ending balance	17,038	17,543
Summit Materials, LLC
Deferred Finance Costs, Own-share Lending Arrangement, Issuance Costs, Accumulated Amortization [Roll Forward]
Beginning balance	15,475	19,033
Loan origination fees	6,246	550
Amortization	(1,832)	(2,040)
Write off of deferred financing fees	(2,851)
Ending balance	$ 17,038	$ 17,543

DEBT - Other (Details)

DEBT - Other (Details) - CAD ($)	Jan. 15, 2015	Jun. 29, 2019	Dec. 29, 2018
Canadian subsidiary credit agreement, Operating activities
Debt Instrument [Line Items]
Revolving credit commitment	$ 6,000,000
Canadian subsidiary credit agreement, Capital equipment
Debt Instrument [Line Items]
Revolving credit commitment	$ 500,000
Basis spread on variable rate	0.90%
Canadian subsidiary credit agreement, Guarantees
Debt Instrument [Line Items]
Revolving credit commitment	$ 400,000
Canadian subsidiary credit agreement
Debt Instrument [Line Items]
Amount outstanding		$ 0	$ 0
Prime rate | Canadian subsidiary credit agreement, Operating activities
Debt Instrument [Line Items]
Basis spread on variable rate	0.20%
Summit Materials, LLC | Canadian subsidiary credit agreement, Operating activities
Debt Instrument [Line Items]
Revolving credit commitment	$ 6,000,000
Summit Materials, LLC | Canadian subsidiary credit agreement, Capital equipment
Debt Instrument [Line Items]
Revolving credit commitment	$ 500,000
Basis spread on variable rate	0.90%
Summit Materials, LLC | Canadian subsidiary credit agreement, Guarantees
Debt Instrument [Line Items]
Revolving credit commitment	$ 400,000
Summit Materials, LLC | Canadian subsidiary credit agreement
Debt Instrument [Line Items]
Amount outstanding		$ 0	$ 0
Summit Materials, LLC | Prime rate | Canadian subsidiary credit agreement, Operating activities
Debt Instrument [Line Items]
Basis spread on variable rate	0.20%

INCOME TAXES - Narrative (Detai

INCOME TAXES - Narrative (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 29, 2019	Jun. 30, 2018	Jun. 29, 2019	Jun. 30, 2018	Dec. 29, 2018
Income Taxes [Line Items]
Income tax expense (benefit)	$ 16,707,000	$ 12,190,000	$ (11,330,000)	$ (4,516,000)
Valuation Allowance
Valuation allowance	27,863,000		27,863,000		$ 19,366,000
Income tax provision, interest or penalties recognized	0	0	0	0
Deferred tax asset, Investment in limited partnership	100,000		100,000
Tax receivable agreement liability	309,733,000		309,733,000		309,674,000
Tax Receivable Agreement
Valuation Allowance
Tax receivable agreement liability	309,700,000		309,700,000		310,300,000
Tax Receivable Agreement | Accrued expenses.
Valuation Allowance
Tax receivable agreement liability					$ 600,000
Summit Holdings LP
Valuation Allowance
Distributions to LP Unitholders			$ 0	100,000
Summit Holdings LP | Tax Receivable Agreement
Valuation Allowance
Percentage of benefits to be paid on tax receivable agreement			85.00%
Summit Materials, LLC
Income Taxes [Line Items]
Income tax expense (benefit)	1,314,000	2,668,000	$ (6,492,000)	(1,176,000)
Valuation Allowance
Income tax provision, interest or penalties recognized	$ 0	$ 0	$ 0	$ 0
Common Class A
Valuation Allowance
Exchanges during period (in shares)			17,500	229,658

EARNINGS PER SHARE - Schedule o

EARNINGS PER SHARE - Schedule of Basic to Diluted Income Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 29, 2019	Jun. 30, 2018	Jun. 29, 2019	Jun. 30, 2018
Reconciliation of basic to diluted loss per share
Net income (loss) attributable to Summit Inc.	$ 36,410	$ 35,509	$ (32,362)	$ (18,220)
Diluted net income (loss) attributable to Summit Inc.	$ 36,410	$ 35,509	$ (32,362)	$ (18,220)
LP Units
Reconciliation of basic to diluted loss per share
Anti dilutive shares excluded from calculation of earnings per share (in shares)	3,418,018	3,517,602	3,418,018	3,583,407
Stock options
Reconciliation of basic to diluted loss per share
Anti dilutive shares excluded from calculation of earnings per share (in shares)	3,168,170	0	3,168,170	3,286,163
Warrants
Reconciliation of basic to diluted loss per share
Anti dilutive shares excluded from calculation of earnings per share (in shares)	100,037	0	100,037	100,037
Time-vesting restricted stock units
Reconciliation of basic to diluted loss per share
Anti dilutive shares excluded from calculation of earnings per share (in shares)	0	0	1,493,119	841,618
Market-based restricted stock units
Reconciliation of basic to diluted loss per share
Anti dilutive shares excluded from calculation of earnings per share (in shares)	0	0	390,645	295,252
Common Class A
Reconciliation of basic to diluted loss per share
Weighted average shares of Class A stock outstanding (in shares)	112,070,009	111,564,190	111,940,844	111,111,644
Basic and diluted loss per share (usd per share)	$ 0.32	$ 0.32	$ (0.29)	$ (0.16)
Weighted average shares of Class A stock outstanding (in shares)	0	36,488	0	0
Weighted average dilutive shares outstanding (in shares)	112,182,555	112,583,321	111,940,844	111,111,644
Diluted earnings (loss) per share (usd per share)	$ 0.32	$ 0.32	$ (0.29)	$ (0.16)
Common Class A | LP Units
Reconciliation of basic to diluted loss per share
Weighted average shares of Class A stock outstanding (in shares)	0	0	0	0
Common Class A | Stock options
Reconciliation of basic to diluted loss per share
Weighted average shares of Class A stock outstanding (in shares)	0	794,065	0	0
Common Class A | Restricted Stock Units (RSUs) [Member]
Reconciliation of basic to diluted loss per share
Weighted average shares of Class A stock outstanding (in shares)	76,539	91,347	0	0
Common Class A | Performance Shares [Member]
Reconciliation of basic to diluted loss per share
Weighted average shares of Class A stock outstanding (in shares)	36,007	97,231	0	0

STOCKHOLDERS' EQUITY_MEMBERS'_3

STOCKHOLDERS' EQUITY/MEMBERS' INTEREST - Equity Offerings (Details) - shares	6 Months Ended
	Jun. 29, 2019	Jun. 30, 2018	Dec. 29, 2018	Dec. 30, 2017
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Other (in shares)	397,067	1,048,986
Ownership percentage	97.00%	97.00%	97.00%	96.80%
Common Class A
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance (in shares)	111,658,927	110,350,594
Exchanges during period (in shares)	17,500	229,658
Other (in shares)	397,067	1,048,986
Ending balance (in shares)	112,073,494	111,629,238
Summit Materials, Inc. and Summit Holdings, LP
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance (in shares)	115,094,445	114,040,214
Exchanges during period (in shares)	0	0
Ending balance (in shares)	115,491,512	115,089,200
LP Units
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Number of LP Units exchanged (in shares)	(17,500)	(229,658)
LP Units | Summit Holdings LP
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Number of LP Units outstanding, beginning balance (in shares)	3,435,518	3,689,620
Number of LP Units outstanding, ending balance (in shares)	3,418,018	3,459,962
Summit Holdings LP
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Noncontrolling interest elimination (as a percent)	3.00%		3.00%

STOCKHOLDERS' EQUITY_MEMBERS'_4

STOCKHOLDERS' EQUITY/MEMBERS' INTEREST - Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 29, 2019	Jun. 30, 2018
Changes in each component of accumulated other comprehensive loss
Beginning balance	$ 1,327,741
Foreign currency translation adjustment, net of tax	3,330	$ (3,721)
Loss on cash flow hedges, net of tax	(220)	980
Ending balance	1,309,511
Summit Materials, LLC
Changes in each component of accumulated other comprehensive loss
Foreign currency translation adjustment, net of tax	4,591	(5,149)
Loss on cash flow hedges, net of tax	(303)	1,356
Change in retirement plans
Changes in each component of accumulated other comprehensive loss
Beginning balance	3,573	2,364
Ending balance	3,573	2,364
Change in retirement plans | Summit Materials, LLC
Changes in each component of accumulated other comprehensive loss
Beginning balance	(4,392)	(6,053)
Ending balance	(4,392)	(6,053)
Foreign currency translation adjustments
Changes in each component of accumulated other comprehensive loss
Beginning balance	(2,147)	4,637
Foreign currency translation adjustment, net of tax	3,330	(3,721)
Ending balance	1,183	916
Foreign currency translation adjustments | Summit Materials, LLC
Changes in each component of accumulated other comprehensive loss
Beginning balance	(19,370)	(10,022)
Foreign currency translation adjustment, net of tax	4,591	(5,149)
Ending balance	(14,779)	(15,171)
Cash flow hedge adjustments
Changes in each component of accumulated other comprehensive loss
Beginning balance	1,255	385
Loss on cash flow hedges, net of tax	(220)	980
Ending balance	1,035	1,365
Cash flow hedge adjustments | Summit Materials, LLC
Changes in each component of accumulated other comprehensive loss
Beginning balance	146	(1,060)
Loss on cash flow hedges, net of tax	(303)	1,356
Ending balance	(157)	296
Accumulated other comprehensive income (loss)
Changes in each component of accumulated other comprehensive loss
Beginning balance	2,681	7,386
Ending balance	5,791	4,645
Accumulated other comprehensive income (loss) | Summit Materials, LLC
Changes in each component of accumulated other comprehensive loss
Beginning balance	(23,616)	(17,135)
Ending balance	$ (19,328)	$ (20,928)

SUPPLEMENTAL CASH FLOW INFORM_3

SUPPLEMENTAL CASH FLOW INFORMATION - Schedule of Supplemental Cash Flow Information (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 29, 2019	Jun. 30, 2018
Cash payments:
Interest	$ 36,834	$ 52,206
Income taxes	1,190	3,061
Operating cash payments on operating leases	5,410
Operating cash payments on finance leases	1,516
Non cash financing activities:	6,000
Right of use assets obtained in exchange for finance leases obligations
Right of use assets obtained in exchange for operating lease obligations	3,298
Right of use assets obtained in exchange for finance leases obligations	16,248
Exchange of LP Units to shares of Class A common stock	277	6,987
Summit Materials, LLC
Cash payments:
Interest	36,834	52,206
Income taxes	1,190	$ 3,061
Operating cash payments on operating leases	5,410
Operating cash payments on finance leases	1,516
Non cash financing activities:	6,000
Right of use assets obtained in exchange for finance leases obligations
Right of use assets obtained in exchange for operating lease obligations	3,298
Right of use assets obtained in exchange for finance leases obligations	$ 16,248

LEASES - Operating and Finance

LEASES - Operating and Finance Leases (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
	Jun. 29, 2019	Jun. 29, 2019	Dec. 30, 2018
Lease, Cost [Abstract]
Operating lease cost	$ 2,694	$ 5,149
Variable lease cost	143	215
Short-term lease cost	9,591	16,172
Financing lease cost:
Amortization of right-of-use assets	2,670	5,293
Interest on lease liabilities	876	1,631
Total lease cost	15,974	28,460
Operating leases:
Operating lease right-of-use assets	34,101	34,101	$ 36,800
Current operating lease liabilities	8,470	8,470
Noncurrent operating lease liabilities	26,614	26,614
Total operating lease liabilities	35,084	35,084	36,800
Finance leases:
Property and equipment, gross	79,911	79,911
Less accumulated depreciation	(21,667)	(21,667)
Property and equipment, net	58,244	58,244
Current finance lease liabilities	17,805	17,805
Long-term finance lease liabilities	41,123	41,123
Total finance lease liabilities	$ 58,928	$ 58,928
Lease Term
Operating leases	7 years 8 months 12 days	7 years 8 months 12 days
Finance lease	2 years 9 months 18 days	2 years 9 months 18 days
Discount Rate
Operating leases	5.60%	5.60%
Finance lease	5.50%	5.50%
Operating Leases
2019 (six months)	$ 5,124	$ 5,124
2020	9,391	9,391
2021	7,434	7,434
2022	4,558	4,558
2023	3,546	3,546
2024	2,413	2,413
Thereafter	11,252	11,252
Total lease payments	43,718	43,718
Less imputed interest	(8,634)	(8,634)
Finance Leases
2019 (six months)	10,115	10,115
2020	17,539	17,539
2021	20,235	20,235
2022	11,745	11,745
2023	1,509	1,509
2024	1,750	1,750
Thereafter	2,662	2,662
Total lease payments	65,555	65,555
Less imputed interest	(6,627)	(6,627)
Summit Materials, LLC
Lease, Cost [Abstract]
Operating lease cost	2,694	5,149
Variable lease cost	143	215
Short-term lease cost	9,591	16,172
Financing lease cost:
Amortization of right-of-use assets	2,670	5,293
Interest on lease liabilities	876	1,631
Total lease cost	15,974	28,460
Operating leases:
Operating lease right-of-use assets	34,101	34,101	36,800
Current operating lease liabilities	8,470	8,470
Noncurrent operating lease liabilities	26,614	26,614
Total operating lease liabilities	35,084	35,084	$ 36,800
Finance leases:
Property and equipment, gross	79,911	79,911
Less accumulated depreciation	(21,667)	(21,667)
Property and equipment, net	58,244	58,244
Current finance lease liabilities	17,805	17,805
Long-term finance lease liabilities	41,123	41,123
Total finance lease liabilities	$ 58,928	$ 58,928
Lease Term
Operating leases	7 years 8 months 12 days	7 years 8 months 12 days
Finance lease	2 years 9 months 18 days	2 years 9 months 18 days
Discount Rate
Operating leases	5.60%	5.60%
Finance lease	5.50%	5.50%
Operating Leases
2019 (six months)	$ 5,124	$ 5,124
2020	9,391	9,391
2021	7,434	7,434
2022	4,558	4,558
2023	3,546	3,546
2024	2,413	2,413
Thereafter	11,252	11,252
Total lease payments	43,718	43,718
Less imputed interest	(8,634)	(8,634)
Finance Leases
2019 (six months)	10,115	10,115
2020	17,539	17,539
2021	20,235	20,235
2022	11,745	11,745
2023	1,509	1,509
2024	1,750	1,750
Thereafter	2,662	2,662
Total lease payments	65,555	65,555
Less imputed interest	$ (6,627)	$ (6,627)

LEASES - Future Minimum Lease P

LEASES - Future Minimum Lease Payments Under Topic 840 (Details) $ in Thousands	Dec. 29, 2018USD ($)
Lessee, Lease, Description [Line Items]
2019	$ 9,479
2020	8,101
2021	6,701
2022	4,279
2023	3,411
Summit Materials, LLC
Lessee, Lease, Description [Line Items]
2019	9,479
2020	8,101
2021	6,701
2022	4,279
2023	$ 3,411

FAIR VALUE - Fair Value Measure

FAIR VALUE - Fair Value Measurements (Details) $ in Thousands	6 Months Ended
	Jun. 29, 2019USD ($)	Jun. 30, 2018USD ($)	Dec. 29, 2018USD ($)
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Current portion of acquisition-related liabilities and accrued expenses - contingent consideration	$ 2,622		$ 1,394
Acquisition-related liabilities and other noncurrent liabilities - contingent consideration	1,238		5,175
Adjustment to contingent consideration	0	$ 0
Cash flow hedges | Interest rate derivatives | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Current portion of acquisition-related liabilities and accrued expenses - cash flow hedge	112		0
Acquisition-related liabilities and other noncurrent liabilities - cash flow hedge	0		0
Cash flow hedges | Interest rate derivatives | Term Loan, due 2022
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Term loan borrowings hedged by derivatives	200,000
Summit Materials, LLC | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Current portion of acquisition-related liabilities and accrued expenses - contingent consideration	2,622		1,394
Acquisition-related liabilities and other noncurrent liabilities - contingent consideration	1,238		5,175
Summit Materials, LLC | Cash flow hedges | Interest rate derivatives | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Current portion of acquisition-related liabilities and accrued expenses - cash flow hedge	112		0
Acquisition-related liabilities and other noncurrent liabilities - cash flow hedge	0		$ 0
Summit Materials, LLC | Cash flow hedges | Interest rate derivatives | Term Loan, due 2022
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Term loan borrowings hedged by derivatives	$ 200,000
Discount Rate | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Contingent consideration fair value measurement input	0.100
Discount Rate | Summit Materials, LLC | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Contingent consideration fair value measurement input	0.100

FAIR VALUE - Carrying Value and

FAIR VALUE - Carrying Value and Fair Value of Financial Instruments (Details) - USD ($) $ in Thousands	Jun. 29, 2019	Dec. 29, 2018
Financial Instruments
Current portion of debt	$ 4,765	$ 6,354
Summit Materials, LLC
Financial Instruments
Current portion of debt	4,765	6,354
Level 2
Financial Instruments
Current portion of debt	4,800	6,400
Level 2 | Fair Value
Financial Instruments
Long-term debt	1,895,932	1,777,722
Level 2 | Carrying Value
Financial Instruments
Long-term debt	1,873,627	1,828,159
Level 2 | Summit Materials, LLC
Financial Instruments
Current portion of debt	4,800	6,400
Level 2 | Summit Materials, LLC | Fair Value
Financial Instruments
Long-term debt	1,895,932	1,777,722
Level 2 | Summit Materials, LLC | Carrying Value
Financial Instruments
Long-term debt	1,873,627	1,828,159
Level 3 | Fair Value
Financial Instruments
Current portion of deferred consideration and noncompete obligations	32,848	32,876
Long term portion of deferred consideration and noncompete obligations	38,850	44,293
Level 3 | Carrying Value
Financial Instruments
Current portion of deferred consideration and noncompete obligations	32,848	32,876
Long term portion of deferred consideration and noncompete obligations	38,850	44,293
Level 3 | Summit Materials, LLC | Fair Value
Financial Instruments
Current portion of deferred consideration and noncompete obligations	30,348	30,376
Long term portion of deferred consideration and noncompete obligations	36,951	40,179
Level 3 | Summit Materials, LLC | Carrying Value
Financial Instruments
Current portion of deferred consideration and noncompete obligations	30,348	30,376
Long term portion of deferred consideration and noncompete obligations	$ 36,951	$ 40,179

COMMITMENTS AND CONTINGENCIES -

COMMITMENTS AND CONTINGENCIES - Additional Information (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 29, 2019	Dec. 29, 2018
Loss Contingencies [Line Items]
Term of purchase commitments	1 year
Site Restoration Obligations
Loss Contingencies [Line Items]
Anticipated costs	$ 90.2	$ 92.5
Site Restoration Obligations | Other noncurrent liabilities
Loss Contingencies [Line Items]
Site restoration obligation, non-current	28.6	26.9
Site Restoration Obligations | Accrued expenses.
Loss Contingencies [Line Items]
Asset retirement obligation, current	$ 3.5	4.1
Summit Materials, LLC
Loss Contingencies [Line Items]
Term of purchase commitments	1 year
Summit Materials, LLC | Site Restoration Obligations
Loss Contingencies [Line Items]
Anticipated costs	$ 90.2	92.5
Summit Materials, LLC | Site Restoration Obligations | Other noncurrent liabilities
Loss Contingencies [Line Items]
Site restoration obligation, non-current	28.6	26.9
Summit Materials, LLC | Site Restoration Obligations | Accrued expenses.
Loss Contingencies [Line Items]
Asset retirement obligation, current	$ 3.5	$ 4.1

SEGMENT INFORMATION - Financial

SEGMENT INFORMATION - Financial Data (Details) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 29, 2019USD ($)	Jun. 30, 2018USD ($)	Jun. 29, 2019USD ($)segment	Jun. 30, 2018USD ($)	Dec. 29, 2018USD ($)
Segment Reporting Information [Line Items]
Number of operating segments | segment			3
Number of reportable segments | segment			3
Total revenue	$ 600,891	$ 600,890	$ 933,530	$ 915,311
Income (loss) from operation before taxes	54,697	49,103	(44,841)	(23,551)
Interest expense	29,401	28,943	59,506	57,727
Depreciation, depletion and amortization	53,035	49,402	107,842	95,945
Accretion	590	329	1,171	744
Loss on debt financings	0	149	14,565	149
Transaction costs	390	1,291	698	2,557
Non-cash compensation	4,699	5,683	10,605	14,190
Other	(2,346)	441	(2,492)	(6,907)
Total Adjusted EBITDA	140,466	135,341	147,054	140,854
Total purchases of property, plant and equipment			105,569	131,657
Total depreciation, depletion, amortization and accretion	53,625	49,731	109,013	96,689
Total assets	3,954,856		3,954,856		$ 3,857,641
West
Segment Reporting Information [Line Items]
Total revenue	300,212	321,713	482,157	503,426
East
Segment Reporting Information [Line Items]
Total revenue	216,132	197,336	329,520	292,493
Cement
Segment Reporting Information [Line Items]
Total revenue	84,547	81,841	121,853	119,392
Operating segment
Segment Reporting Information [Line Items]
Total purchases of property, plant and equipment			104,785	127,938
Total depreciation, depletion, amortization and accretion	52,633	49,096	107,069	95,344
Total assets	3,632,698		3,632,698		3,501,727
Operating segment | West
Segment Reporting Information [Line Items]
Total Adjusted EBITDA	54,820	61,227	69,118	77,400
Total purchases of property, plant and equipment			51,517	76,223
Total depreciation, depletion, amortization and accretion	22,924	22,589	46,849	44,740
Total assets	1,437,583		1,437,583		1,370,501
Operating segment | East
Segment Reporting Information [Line Items]
Total Adjusted EBITDA	54,412	45,395	57,654	42,192
Total purchases of property, plant and equipment			41,801	37,303
Total depreciation, depletion, amortization and accretion	19,840	17,826	40,051	35,553
Total assets	1,307,364		1,307,364		1,253,640
Operating segment | Cement
Segment Reporting Information [Line Items]
Total Adjusted EBITDA	35,441	34,660	32,854	38,327
Total purchases of property, plant and equipment			11,467	14,412
Total depreciation, depletion, amortization and accretion	9,869	8,681	20,169	15,051
Total assets	887,751		887,751		877,586
Corporate, Non-Segment
Segment Reporting Information [Line Items]
Total Adjusted EBITDA	(4,207)	(5,941)	(12,572)	(17,065)
Total purchases of property, plant and equipment			784	3,719
Total depreciation, depletion, amortization and accretion	992	635	1,944	1,345
Total assets	322,158		$ 322,158		355,914
Summit Materials, LLC
Segment Reporting Information [Line Items]
Number of operating segments | segment			3
Number of reportable segments | segment			3
Total revenue	600,891	600,890	$ 933,530	915,311
Income (loss) from operation before taxes	54,815	49,270	(44,555)	(23,170)
Interest expense	29,283	28,776	59,220	57,346
Depreciation, depletion and amortization	53,035	49,402	107,842	95,945
Accretion	590	329	1,171	744
Loss on debt financings	0	149	14,565	149
Transaction costs	390	1,291	698	2,557
Non-cash compensation	4,699	5,683	10,605	14,190
Other	(2,346)	441	(2,492)	(6,907)
Total Adjusted EBITDA	140,466	135,341	147,054	140,854
Total purchases of property, plant and equipment			105,569	131,657
Total depreciation, depletion, amortization and accretion	53,625	49,731	109,013	96,689
Total assets	3,718,767		3,718,767		3,633,244
Summit Materials, LLC | West
Segment Reporting Information [Line Items]
Total revenue	300,212	321,713	482,157	503,426
Summit Materials, LLC | East
Segment Reporting Information [Line Items]
Total revenue	216,132	197,336	329,520	292,493
Summit Materials, LLC | Cement
Segment Reporting Information [Line Items]
Total revenue	84,547	81,841	121,853	119,392
Summit Materials, LLC | Operating segment
Segment Reporting Information [Line Items]
Total purchases of property, plant and equipment			104,785	127,938
Total depreciation, depletion, amortization and accretion	52,633	49,096	107,069	95,344
Total assets	3,632,698		3,632,698		3,501,727
Summit Materials, LLC | Operating segment | West
Segment Reporting Information [Line Items]
Total Adjusted EBITDA	54,820	61,227	69,118	77,400
Total purchases of property, plant and equipment			51,517	76,223
Total depreciation, depletion, amortization and accretion	22,924	22,589	46,849	44,740
Total assets	1,437,583		1,437,583		1,370,501
Summit Materials, LLC | Operating segment | East
Segment Reporting Information [Line Items]
Total Adjusted EBITDA	54,412	45,395	57,654	42,192
Total purchases of property, plant and equipment			41,801	37,303
Total depreciation, depletion, amortization and accretion	19,840	17,826	40,051	35,553
Total assets	1,307,364		1,307,364		1,253,640
Summit Materials, LLC | Operating segment | Cement
Segment Reporting Information [Line Items]
Total Adjusted EBITDA	35,441	34,660	32,854	38,327
Total purchases of property, plant and equipment			11,467	14,412
Total depreciation, depletion, amortization and accretion	9,869	8,681	20,169	15,051
Total assets	887,751		887,751		877,586
Summit Materials, LLC | Corporate, Non-Segment
Segment Reporting Information [Line Items]
Total Adjusted EBITDA	(4,207)	(5,941)	(12,572)	(17,065)
Total purchases of property, plant and equipment			784	3,719
Total depreciation, depletion, amortization and accretion	992	$ 635	1,944	$ 1,345
Total assets	$ 86,069		$ 86,069		$ 131,517

GUARANTOR AND NON-GUARANTOR F_3

GUARANTOR AND NON-GUARANTOR FINANCIAL INFORMATION - Schedule of Condensed Consolidating Balance Sheets (Details) - USD ($) $ in Thousands	Jun. 29, 2019	Mar. 30, 2019	Dec. 30, 2018	Dec. 29, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 30, 2017
Current assets:
Cash and cash equivalents	$ 67,658			$ 128,508
Accounts receivable, net	294,604			214,518
Cost and estimated earnings in excess of billings	45,371			18,602
Inventories	208,136			213,851
Other current assets	12,618			16,061
Total current assets	628,387			591,540
Property, plant and equipment, net	1,788,664			1,780,132
Goodwill	1,198,177			1,192,028
Intangible assets, net	17,653			18,460
Operating lease right-of-use assets	34,101		$ 36,800
Other assets	50,785			50,084
Total assets	3,954,856			3,857,641
Current liabilities:
Current portion of debt	4,765			6,354
Current portion of acquisition-related liabilities	35,470			34,270
Accounts payable	131,391			107,702
Accrued expenses	113,996			100,491
Current operating lease liabilities	8,470
Billings in excess of costs and estimated earnings	10,733			11,840
Total current liabilities	304,825			260,657
Long-term debt	1,854,189			1,807,502
Acquisition-related liabilities	40,088			49,468
Noncurrent operating lease liabilities	26,614
Other noncurrent liabilities	96,636			88,195
Total liabilities	2,632,085			2,515,496
Total liabilities and stockholders’ equity/member's interest	3,954,856			3,857,641
Summit Materials, LLC
Current assets:
Cash and cash equivalents	67,658			128,508	$ 50,404		$ 383,556
Accounts receivable, net	294,604			214,518
Intercompany receivables	0			0
Cost and estimated earnings in excess of billings	45,371			18,602
Inventories	208,136			213,851
Other current assets	12,618			16,061
Total current assets	628,387			591,540
Property, plant and equipment, net	1,788,664			1,780,132
Goodwill	1,199,177			1,193,028
Intangible assets, net	17,653			18,460
Operating lease right-of-use assets	34,101		$ 36,800
Other assets	50,785			50,084
Total assets	3,718,767			3,633,244
Current liabilities:
Current portion of debt	4,765			6,354
Current portion of acquisition-related liabilities	32,970			31,770
Accounts payable	132,002			109,008
Accrued expenses	114,228			100,029
Current operating lease liabilities	8,470
Intercompany payables	0			0
Billings in excess of costs and estimated earnings	10,733			11,840
Total current liabilities	303,168			259,001
Long-term debt	1,854,189			1,807,502
Acquisition-related liabilities	38,189			45,354
Noncurrent operating lease liabilities	26,614
Other noncurrent liabilities	136,563			135,956
Total liabilities	2,358,723			2,247,813
Total member's interest	1,360,044	$ 1,299,730		1,385,431	1,291,139	$ 1,240,542	1,291,594
Total liabilities and stockholders’ equity/member's interest	3,718,767			3,633,244
Summit Materials, LLC | Eliminations
Current assets:
Cash and cash equivalents	(6,302)			(4,870)	(11,188)		(12,372)
Accounts receivable, net	(218)			(185)
Intercompany receivables	(1,105,598)			(1,125,192)
Cost and estimated earnings in excess of billings	0			0
Inventories	0			0
Other current assets	0			0
Total current assets	(1,112,118)			(1,130,247)
Property, plant and equipment, net	0			0
Goodwill	0			0
Intangible assets, net	0			0
Operating lease right-of-use assets	0
Other assets	(3,476,200)			(3,397,794)
Total assets	(4,588,318)			(4,528,041)
Current liabilities:
Current portion of debt	0			0
Current portion of acquisition-related liabilities	0			0
Accounts payable	(218)			(185)
Accrued expenses	(6,302)			(4,870)
Current operating lease liabilities	0
Intercompany payables	(1,105,598)			(1,125,192)
Billings in excess of costs and estimated earnings	0			0
Total current liabilities	(1,112,118)			(1,130,247)
Long-term debt	0			0
Acquisition-related liabilities	0			0
Noncurrent operating lease liabilities	0
Other noncurrent liabilities	(137,020)			(171,317)
Total liabilities	(1,249,138)			(1,301,564)
Total member's interest	(3,339,180)			(3,226,477)
Total liabilities and stockholders’ equity/member's interest	(4,588,318)			(4,528,041)
Summit Materials, LLC | Issuers | Reportable Legal Entities
Current assets:
Cash and cash equivalents	69,466			117,219	53,003		370,741
Accounts receivable, net	0			0
Intercompany receivables	465,120			500,765
Cost and estimated earnings in excess of billings	0			0
Inventories	0			0
Other current assets	1,279			1,953
Total current assets	535,865			619,937
Property, plant and equipment, net	12,008			13,300
Goodwill	0			0
Intangible assets, net	0			0
Operating lease right-of-use assets	3,653
Other assets	3,367,863			3,292,851
Total assets	3,919,389			3,926,088
Current liabilities:
Current portion of debt	4,765			6,354
Current portion of acquisition-related liabilities	0			0
Accounts payable	2,367			4,712
Accrued expenses	47,231			45,146
Current operating lease liabilities	735
Intercompany payables	642,397			673,175
Billings in excess of costs and estimated earnings	0			0
Total current liabilities	697,495			729,387
Long-term debt	1,854,189			1,807,502
Acquisition-related liabilities	0			0
Noncurrent operating lease liabilities	3,867
Other noncurrent liabilities	3,794			3,768
Total liabilities	2,559,345			2,540,657
Total member's interest	1,360,044			1,385,431
Total liabilities and stockholders’ equity/member's interest	3,919,389			3,926,088
Summit Materials, LLC | 100% Owned Guarantors | Reportable Legal Entities
Current assets:
Cash and cash equivalents	3,712			8,440	5,528		10,254
Accounts receivable, net	274,291			199,538
Intercompany receivables	640,478			624,427
Cost and estimated earnings in excess of billings	43,308			17,711
Inventories	204,291			210,149
Other current assets	8,025			11,308
Total current assets	1,174,105			1,071,573
Property, plant and equipment, net	1,713,138			1,709,083
Goodwill	1,140,580			1,136,785
Intangible assets, net	17,653			18,460
Operating lease right-of-use assets	25,015
Other assets	158,299			154,080
Total assets	4,228,790			4,089,981
Current liabilities:
Current portion of debt	0			0
Current portion of acquisition-related liabilities	32,970			31,770
Accounts payable	118,300			92,132
Accrued expenses	70,818			57,826
Current operating lease liabilities	6,681
Intercompany payables	445,051			436,564
Billings in excess of costs and estimated earnings	9,897			11,347
Total current liabilities	683,717			629,639
Long-term debt	0			0
Acquisition-related liabilities	38,189			45,354
Noncurrent operating lease liabilities	18,454
Other noncurrent liabilities	192,351			226,137
Total liabilities	932,711			901,130
Total member's interest	3,296,079			3,188,851
Total liabilities and stockholders’ equity/member's interest	4,228,790			4,089,981
Summit Materials, LLC | Non-Guarantors | Reportable Legal Entities
Current assets:
Cash and cash equivalents	782			7,719	$ 3,061		$ 14,933
Accounts receivable, net	20,531			15,165
Intercompany receivables	0			0
Cost and estimated earnings in excess of billings	2,063			891
Inventories	3,845			3,702
Other current assets	3,314			2,800
Total current assets	30,535			30,277
Property, plant and equipment, net	63,518			57,749
Goodwill	58,597			56,243
Intangible assets, net	0			0
Operating lease right-of-use assets	5,433
Other assets	823			947
Total assets	158,906			145,216
Current liabilities:
Current portion of debt	0			0
Current portion of acquisition-related liabilities	0			0
Accounts payable	11,553			12,349
Accrued expenses	2,481			1,927
Current operating lease liabilities	1,054
Intercompany payables	18,150			15,453
Billings in excess of costs and estimated earnings	836			493
Total current liabilities	34,074			30,222
Long-term debt	0			0
Acquisition-related liabilities	0			0
Noncurrent operating lease liabilities	4,293
Other noncurrent liabilities	77,438			77,368
Total liabilities	115,805			107,590
Total member's interest	43,101			37,626
Total liabilities and stockholders’ equity/member's interest	$ 158,906			$ 145,216

GUARANTOR AND NON-GUARANTOR F_4

GUARANTOR AND NON-GUARANTOR FINANCIAL INFORMATION - Schedule of Condensed Consolidating Statements of Operations and Comprehensive Loss (Details) - USD ($) $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 29, 2019	Mar. 30, 2019	Jun. 30, 2018	Mar. 31, 2018	Jun. 29, 2019	Jun. 30, 2018
Condensed Consolidating Statements of Operations
Revenue	$ 600,891		$ 600,890		$ 933,530	$ 915,311
Cost of revenue (excluding items shown separately below)	405,493		410,932		672,497	658,793
Depreciation, depletion, amortization and accretion	53,625		49,731		109,013	96,689
Operating income	80,422		77,279		22,751	25,754
Income (loss) from operation before taxes	54,697		49,103		(44,841)	(23,551)
Income tax expense (benefit)	16,707		12,190		(11,330)	(4,516)
Net income (loss) attributable to Summit Inc.	36,410		35,509		(32,362)	(18,220)
Comprehensive (loss) income attributable to member of Summit Materials, LLC	38,002		35,331		(29,186)	(20,961)
Net income (loss)	37,990	$ (71,501)	36,913	$ (55,948)	(33,511)	(19,035)
Summit Materials, LLC
Condensed Consolidating Statements of Operations
Revenue	600,891		600,890		933,530	915,311
Cost of revenue (excluding items shown separately below)	405,493		410,932		672,497	658,793
General and administrative expenses	61,351		62,948		129,269	134,075
Depreciation, depletion, amortization and accretion	53,625		49,731		109,013	96,689
Operating income	80,422		77,279		22,751	25,754
Other (income) loss, net	(3,676)		(767)		8,086	(8,422)
Interest expense (income)	29,283		28,776		59,220	57,346
Income (loss) from operation before taxes	54,815		49,270		(44,555)	(23,170)
Income tax expense (benefit)	1,314		2,668		(6,492)	(1,176)
Net income (loss) attributable to Summit Inc.	53,501		46,602		(38,063)	(21,994)
Comprehensive (loss) income attributable to member of Summit Materials, LLC	55,597		44,918		(33,775)	(25,787)
Net income (loss)	53,501	$ (91,564)	46,602	$ (68,596)	(38,063)	(21,994)
Summit Materials, LLC | Eliminations
Condensed Consolidating Statements of Operations
Revenue	(2,761)		(1,619)		(3,944)	(3,037)
Cost of revenue (excluding items shown separately below)	(2,761)		(1,619)		(3,944)	(3,037)
General and administrative expenses	0		0		0	0
Depreciation, depletion, amortization and accretion	0		0		0	0
Operating income	0		0		0	0
Other (income) loss, net	95,001		89,481		65,497	71,267
Interest expense (income)	0		0		0	0
Income (loss) from operation before taxes	(95,001)		(89,481)		(65,497)	(71,267)
Income tax expense (benefit)	0		0		0	0
Net income (loss) attributable to Summit Inc.	(95,001)		(89,481)		(65,497)	(71,267)
Comprehensive (loss) income attributable to member of Summit Materials, LLC	(92,905)		(91,165)		(61,209)	(75,060)
Issuers | Summit Materials, LLC | Reportable Legal Entities
Condensed Consolidating Statements of Operations
Revenue	0		0		0	0
Cost of revenue (excluding items shown separately below)	0		0		0	0
General and administrative expenses	9,353		13,276		24,284	34,224
Depreciation, depletion, amortization and accretion	992		635		1,945	1,345
Operating income	(10,345)		(13,911)		(26,229)	(35,569)
Other (income) loss, net	(95,320)		(89,659)		(51,710)	(72,294)
Interest expense (income)	31,022		28,946		62,718	58,527
Income (loss) from operation before taxes	53,953		46,802		(37,237)	(21,802)
Income tax expense (benefit)	452		200		826	192
Net income (loss) attributable to Summit Inc.	53,501		46,602		(38,063)	(21,994)
Comprehensive (loss) income attributable to member of Summit Materials, LLC	55,597		44,918		(33,775)	(25,787)
100% Owned Guarantors | Summit Materials, LLC | Reportable Legal Entities
Condensed Consolidating Statements of Operations
Revenue	578,157		580,157		896,338	880,815
Cost of revenue (excluding items shown separately below)	390,640		396,629		646,807	634,756
General and administrative expenses	49,288		47,287		99,319	94,463
Depreciation, depletion, amortization and accretion	51,167		47,929		104,087	92,922
Operating income	87,062		88,312		46,125	58,674
Other (income) loss, net	(2,985)		(687)		(4,926)	(7,544)
Interest expense (income)	(2,947)		(1,362)		(5,911)	(3,565)
Income (loss) from operation before taxes	92,994		90,361		56,962	69,783
Income tax expense (benefit)	85		2,036		(7,652)	(1,417)
Net income (loss) attributable to Summit Inc.	92,909		88,325		64,614	71,200
Comprehensive (loss) income attributable to member of Summit Materials, LLC	93,046		87,964		64,917	69,844
Non-Guarantors | Summit Materials, LLC | Reportable Legal Entities
Condensed Consolidating Statements of Operations
Revenue	25,495		22,352		41,136	37,533
Cost of revenue (excluding items shown separately below)	17,614		15,922		29,634	27,074
General and administrative expenses	2,710		2,385		5,666	5,388
Depreciation, depletion, amortization and accretion	1,466		1,167		2,981	2,422
Operating income	3,705		2,878		2,855	2,649
Other (income) loss, net	(372)		98		(775)	149
Interest expense (income)	1,208		1,192		2,413	2,384
Income (loss) from operation before taxes	2,869		1,588		1,217	116
Income tax expense (benefit)	777		432		334	49
Net income (loss) attributable to Summit Inc.	2,092		1,156		883	67
Comprehensive (loss) income attributable to member of Summit Materials, LLC	$ (141)		$ 3,201		$ (3,708)	$ 5,216

GUARANTOR AND NON-GUARANTOR F_5

GUARANTOR AND NON-GUARANTOR FINANCIAL INFORMATION - Schedule of Condensed Consolidating Statements of Cash Flows (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 29, 2019	Jun. 30, 2018
Condensed Consolidating Statements of Operations
Net cash (used in) provided by operating activities	$ 15,948	$ (33,718)
Cash flow from investing activities:
Acquisitions, net of cash acquired	(2,842)	(153,196)
Purchase of property, plant and equipment	(105,569)	(131,657)
Proceeds from the sale of property, plant, and equipment	8,005	14,110
Other	(439)	684
Net cash used for investing activities	(100,845)	(270,059)
Cash flow from financing activities:
Net proceeds from debt issuance	300,000	0
Payments on long-term debt	(261,025)	(10,772)
Payments on acquisition-related liabilities	(9,158)	(31,224)
Debt issuance costs	(6,246)	(550)
Distributions from partnership	0	(69)
Other	(502)	(1,904)
Net cash provided by (used in) financing activities	23,853	(28,904)
Cash — Beginning of period	128,508
Cash — End of period	67,658
Summit Materials, LLC
Condensed Consolidating Statements of Operations
Net cash (used in) provided by operating activities	15,948	(33,718)
Cash flow from investing activities:
Acquisitions, net of cash acquired	(2,842)	(153,196)
Purchase of property, plant and equipment	(105,569)	(131,657)
Proceeds from the sale of property, plant, and equipment	8,005	14,110
Other	(439)	684
Net cash used for investing activities	(100,845)	(270,059)
Cash flow from financing activities:
Proceeds from investment by member	784	15,615
Net proceeds from debt issuance	300,000	0
Loans received from and payments made on loans from other Summit Companies	0	0
Payments on long-term debt	(261,025)	(10,772)
Payments on acquisition-related liabilities	(6,658)	(28,724)
Debt issuance costs	(6,246)	(550)
Distributions from partnership	(2,500)	(2,569)
Other	(502)	(1,904)
Net cash provided by (used in) financing activities	23,853	(28,904)
Impact of cash on foreign currency	194	(471)
Net (decrease) increase in cash	(60,850)	(333,152)
Cash — Beginning of period	128,508	383,556
Cash — End of period	67,658	50,404
Summit Materials, LLC | Eliminations
Condensed Consolidating Statements of Operations
Net cash (used in) provided by operating activities	0	0
Cash flow from investing activities:
Acquisitions, net of cash acquired	0	0
Purchase of property, plant and equipment	0	0
Proceeds from the sale of property, plant, and equipment	0	0
Other	0	0
Net cash used for investing activities	0	0
Cash flow from financing activities:
Proceeds from investment by member	0	0
Net proceeds from debt issuance	0
Loans received from and payments made on loans from other Summit Companies	(1,432)	1,184
Payments on long-term debt	0	0
Payments on acquisition-related liabilities	0	0
Debt issuance costs	0	0
Distributions from partnership	0	0
Other	0	0
Net cash provided by (used in) financing activities	(1,432)	1,184
Impact of cash on foreign currency	0	0
Net (decrease) increase in cash	(1,432)	1,184
Cash — Beginning of period	(4,870)	(12,372)
Cash — End of period	(6,302)	(11,188)
Summit Materials, LLC | Issuers | Reportable Legal Entities
Condensed Consolidating Statements of Operations
Net cash (used in) provided by operating activities	(43,760)	(70,942)
Cash flow from investing activities:
Acquisitions, net of cash acquired	0	0
Purchase of property, plant and equipment	(785)	(3,718)
Proceeds from the sale of property, plant, and equipment	0	0
Other	0	0
Net cash used for investing activities	(785)	(3,718)
Cash flow from financing activities:
Proceeds from investment by member	(36,356)	(100,271)
Net proceeds from debt issuance	300,000
Loans received from and payments made on loans from other Summit Companies	(2,879)	(135,634)
Payments on long-term debt	(254,765)	(3,178)
Payments on acquisition-related liabilities	0	0
Debt issuance costs	(6,246)	(550)
Distributions from partnership	(2,500)	(2,569)
Other	(462)	(876)
Net cash provided by (used in) financing activities	(3,208)	(243,078)
Impact of cash on foreign currency	0	0
Net (decrease) increase in cash	(47,753)	(317,738)
Cash — Beginning of period	117,219	370,741
Cash — End of period	69,466	53,003
Summit Materials, LLC | 100% Owned Guarantors | Reportable Legal Entities
Condensed Consolidating Statements of Operations
Net cash (used in) provided by operating activities	59,190	34,740
Cash flow from investing activities:
Acquisitions, net of cash acquired	(2,842)	(153,196)
Purchase of property, plant and equipment	(96,883)	(115,967)
Proceeds from the sale of property, plant, and equipment	7,940	13,950
Other	(439)	684
Net cash used for investing activities	(92,224)	(254,529)
Cash flow from financing activities:
Proceeds from investment by member	37,140	115,886
Net proceeds from debt issuance	0
Loans received from and payments made on loans from other Summit Companies	3,997	136,483
Payments on long-term debt	(6,133)	(7,587)
Payments on acquisition-related liabilities	(6,658)	(28,724)
Debt issuance costs	0	0
Distributions from partnership	0	0
Other	(40)	(995)
Net cash provided by (used in) financing activities	28,306	215,063
Impact of cash on foreign currency	0	0
Net (decrease) increase in cash	(4,728)	(4,726)
Cash — Beginning of period	8,440	10,254
Cash — End of period	3,712	5,528
Summit Materials, LLC | Non-Guarantors | Reportable Legal Entities
Condensed Consolidating Statements of Operations
Net cash (used in) provided by operating activities	518	2,484
Cash flow from investing activities:
Acquisitions, net of cash acquired	0	0
Purchase of property, plant and equipment	(7,901)	(11,972)
Proceeds from the sale of property, plant, and equipment	65	160
Other	0	0
Net cash used for investing activities	(7,836)	(11,812)
Cash flow from financing activities:
Proceeds from investment by member	0	0
Net proceeds from debt issuance	0
Loans received from and payments made on loans from other Summit Companies	314	(2,033)
Payments on long-term debt	(127)	(7)
Payments on acquisition-related liabilities	0	0
Debt issuance costs	0	0
Distributions from partnership	0	0
Other	0	(33)
Net cash provided by (used in) financing activities	187	(2,073)
Impact of cash on foreign currency	194	(471)
Net (decrease) increase in cash	(6,937)	(11,872)
Cash — Beginning of period	7,719	14,933
Cash — End of period	$ 782	$ 3,061