Business Combinations And Discontinued Operations (Narrative) (Details) (USD $)	1 Months Ended	9 Months Ended
May 31, 2011	Sep. 30, 2011 T
Business Combinations And Discontinued Operations
Noncontrolling interest, ownership percentage by noncontrolling owners	1.00%
Purchase of remaining interest in existing limited liability company	$ 10,394,000	$ 10,394,000
Elimination of noncontrolling interest	3,439,000	(7,176,000)
Additional paid-in capital	3,737,000
Deferred tax asset	$ 3,218,000
Tons of limestone reserves acquired with acquisition		200,000,000

Business Combinations And Discontinued Operations [Abstract]

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- Definition

Deferred Tax Asset Recognized from Minority Interest Redemption

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- Definition

Tons of Limestone Reserves Acquired with Acquisition

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Represents increases or decreases in additional paid in capital not separately disclosed.

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- Definition

Decrease in noncontrolling interest (for example, but not limited to, redeeming or purchasing the interests of noncontrolling shareholders, issuance of shares (interests) by the non-wholly owned subsidiary to the parent entity for other than cash, and a buyback of shares (interest) by the non-wholly owned subsidiary from the noncontrolling interests).

+ References

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

-Publisher AICPA

-Name Accounting Research Bulletin (ARB)

-Number 51

-Paragraph 38

-Subparagraph c(2)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.3-04)

-URI http://asc.fasb.org/extlink&oid=6959260&loc=d3e187085-122770

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 810

-SubTopic 10

-Section 45

-Paragraph 23

-URI http://asc.fasb.org/extlink&oid=6921628&loc=SL4569655-111683

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 810

-SubTopic 10

-Section 45

-Paragraph 24

-URI http://asc.fasb.org/extlink&oid=6921628&loc=SL4616395-111683

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The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

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The cash outflow associated with the purchase of noncontrolling interest during the period.

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 17

-Subparagraph b

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 13

-Subparagraph (b)

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