Commitments and Contingencies	9 Months Ended
Commitments and Contingencies	Sep. 30, 2017
Commitments and Contingencies	11. 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 pending or threatened claims and litigation will not have a material effect on the Company’s consolidated results of operations, financial position or liquidity. The Company records legal fees as incurred. Litigation and Claims—The Company is obligated under an indemnification agreement entered into with the sellers of Harper Contracting, Inc., Harper Sand and Gravel, Inc., Harper Excavating, Inc., Harper Ready Mix Company, Inc. and Harper Investments, Inc. for the sellers’ ownership interests in a joint venture agreement. The Company has the rights to any benefits under the joint venture as well as the assumption of any obligations, but does not own equity interests in the joint venture. The joint venture incurred significant losses on a highway project in Utah, which resulted in requests for funding from the joint venture partners and ultimately from the Company. Through September 30, 2017, the Company has funded $12.3 million. In the third quarter of 2017, the Company settled its remaining obligations under this agreement for $3.5 million, which was $0.8 million less than amounts previously accrued under the agreement. 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 September 30, 2017 and December 31, 2016, $21.1 million and $18.8 million, respectively, were included in other noncurrent liabilities on the consolidated balance sheets and $6.2 million and $5.1 million, respectively, were included in accrued expenses for future reclamation costs. The total undiscounted anticipated costs for site reclamation as of September 30, 2017 and December 31, 2016 were $72.5 million and $63.6 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
Commitments and Contingencies	10.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 pending or threatened claims and litigation will not have a material effect on the Company’s consolidated results of operations, financial position or liquidity. The Company records legal fees as incurred. Litigation and Claims—The Company is obligated under an indemnification agreement entered into with the sellers of Harper Contracting, Inc., Harper Sand and Gravel, Inc., Harper Excavating, Inc., Harper Ready Mix Company, Inc. and Harper Investments, Inc. for the sellers’ ownership interests in a joint venture agreement. The Company has the rights to any benefits under the joint venture as well as the assumption of any obligations, but does not own equity interests in the joint venture. The joint venture incurred significant losses on a highway project in Utah, which resulted in requests for funding from the joint venture partners and ultimately from the Company. Through September 30, 2017, the Company has funded $12.3 million. In the third quarter of 2017, the Company settled its remaining obligations under this agreement for $3.5 million, which was $0.8 million less than amounts previously accrued under the agreement. 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 September 30, 2017 and December 31, 2016, $21.1 million and $18.8 million, respectively, were included in other noncurrent liabilities on the consolidated balance sheets and $6.2 million and $5.1 million, respectively, were included in accrued expenses for future reclamation costs. The total undiscounted anticipated costs for site reclamation as of September 30, 2017 and December 31, 2016 were $72.5 million and $63.6 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.