Business Combinations And Discontinued Operations (Narrative) (Details) (USD $)	1 Months Ended	6 Months Ended
May 31, 2011	Jun. 30, 2011 T
Business Combinations And Discontinued Operations
Noncontrolling interest, ownership percentage by noncontrolling owners	1.00%
Payment to purchase minority interest	$ 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

Reduction In Additional Paid in Capital From Minority Interest Redemption.

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- Definition

Tons of Limestone Reserves Acquired with Acquisition

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- Definition

Decrease in noncontrolling interest as a result of redeeming or purchasing the interests of noncontrolling shareholders.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 51
-Paragraph 38
-Subparagraph c(2)

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- Definition

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

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 95
-Paragraph 17
-Subparagraph b

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