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Commitments and Contingencies (Details) (USD $)	3 Months Ended
	Jun. 30, 2012	Jun. 30, 2010	Mar. 31, 2013	Jul. 19, 2012	Jun. 30, 2007
Commitments and Contingencies (Textual) [Abstract]
Class Action settlement amount				$ 12,500,000
Insurance retainer payment	200,000	200,000
Plaintiffs' attorney's fees included in Accrued Liabilities				750,000
Company made payments to Lower Willamette Group as interim settlement					175,000
Maximum amount anticipated to spend for further Source Control work			50,000
Total stand by letters of credit			$ 3,100,000

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Accrued liabilities related to attorney fees payable for plaintiff claim.

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- Definition

Amount of consideration the entity has agreed to pay to settle a legal matter.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 50

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-URI http://asc.fasb.org/extlink&oid=6952336&loc=d3e14326-108349



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-Name Statement of Financial Accounting Standard (FAS)

-Number 95

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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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