Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Sep. 29, 2018	Dec. 30, 2017
Property, plant and equipment, accumulated depreciation, depletion and amortization	$ 748,265	$ 631,841
Intangible assets, accumulated amortization	7,819	6,698
Deferred tax assets, valuation allowance	1,675	1,675
Summit Materials, LLC
Property, plant and equipment, accumulated depreciation, depletion and amortization	748,265	631,841
Intangible assets, accumulated amortization	$ 7,819	$ 6,698
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)	111,654,552	110,350,594
Common stock, shares outstanding (in shares)	111,654,552	110,350,594
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	100
Common stock, shares outstanding (in shares)	99	100