Noncash Investing and Financing Activities (Detail) (USD $) In Thousands, unless otherwise specified	9 Months Ended
Sep. 30, 2014
Schedule of Cash Flow, Supplemental
Acquisition of assets through capital lease	$ 7,788
Acquisition of land through seller financing	1,500
Acquisition of land through asset swap	2,091
Acquisition of TXI assets and liabilities assumed through issuances of common stock and options (See Note 2)	$ 2,691,986

Noncash or Part Noncash Acquisition, Properties Acquired, Through Asset Swap

No definition available.

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- Definition

Amount of equity interests of the acquirer, including instruments or interests issued or issuable in consideration for the business combination.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 30

-Section 30

-Paragraph 7

-URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6578-128477

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 30

-Section 30

-Paragraph 8

-URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6613-128477

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- Definition

Future cash outflow to pay for purchases of fixed assets that have occurred.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 50

-Paragraph 5

-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4332-108586

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 50

-Paragraph 4

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

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-Section 50

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4304-108586

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- Definition

The amount of assets that an Entity acquires in a noncash (or part noncash) acquisition that are not presented as a separate disclosure or not otherwise listed in the existing taxonomy. Noncash is defined as information about all investing and financing activities of an enterprise during a period that affect recognized assets or liabilities but that do not result in cash receipts or cash payments in the period.

+ References

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