Inventories - Components of Inventories (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 27, 2014	Dec. 28, 2013
Inventory Disclosure [Abstract]
Aggregate stockpiles	$ 88,211	$ 70,300
Finished goods	8,826us-gaap_InventoryFinishedGoods	11,207us-gaap_InventoryFinishedGoods
Work in process	1,801us-gaap_InventoryWorkInProcess	2,623us-gaap_InventoryWorkInProcess
Raw materials	12,715us-gaap_InventoryRawMaterials	12,302us-gaap_InventoryRawMaterials
Total	$ 111,553us-gaap_InventoryNet	$ 96,432us-gaap_InventoryNet

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Amount before valuation and LIFO reserves of completed merchandise or goods expected to be sold within one year or operating cycle, if longer.

+ References

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 6

-Subparagraph a

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.6(a)(1))

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

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-Publisher FASB

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-Topic 330

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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.

+ References

No definition available.

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 6

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-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

-Topic 210

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Amount before valuation and LIFO reserves of merchandise or goods in the production process expected to be completed within one year or operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 6

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-Name Accounting Standards Codification

-Topic 210

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-Section S99

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