Inventories - Components of Inventories (Details) - Summit Materials, LLC - USD ($) $ in Thousands	Jul. 02, 2016	Jan. 02, 2016	Dec. 27, 2014
Inventories
Aggregate stockpiles	$ 103,216	$ 86,236	$ 88,211
Finished goods	46,171	14,840
Work in process	8,052	5,141
Raw materials	17,300	23,865
Total	$ 174,739	$ 130,082	$ 111,553

Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of merchandise or goods held by the company that are readily available for sale.

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Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

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Amount before last-in first-out (LIFO) and valuation reserves of ore stockpile material contained on a leach pad, for example, but not limited to, copper or gold ore.

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Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of unprocessed items to be consumed in the manufacturing or production process.

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Carrying amount, net of reserves and adjustments, as of the balance sheet date of merchandise or goods which are partially completed. This inventory is generally comprised of raw materials, labor and factory overhead costs, which require further materials, labor and overhead to be converted into finished goods, and which generally require the use of estimates to determine percentage complete and pricing.

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