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

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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