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Commitments And Contingencies (Details) (USD $) | 3 Months Ended |  |  |
--- | --- | --- | --- | ---
Jun. 30, 2012 | Jun. 30, 2010 | Dec. 31, 2012 | Jul. 19, 2012 | Jun. 30, 2007
Commitments and Contingencies (Textual) [Abstract] |  |  |  |  |
Amount anticipated to spent for further Source Control work |  |  | $ 50,000 |  |
Company made payments to Lower Willamette Group as interim settlement |  |  |  |  | 175,000
Amount spent to complete work specified in Work Plans |  |  | 2,500,000 |  |
Total stand by letters of credit |  |  | 3,200,000 |  |
Class Action settlement amount |  |  |  | 12,500,000 |
Insurance retainer payment | 200,000 | 200,000 |  |  |
Plaintiffs' attorney's fees included in Accrued Liabilities |  |  |  | $ 750,000 |

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- Definition Amount of consideration the entity has agreed to pay to settle a legal matter. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6952336&loc=d3e14326-108349 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6952336&loc=d3e14435-108349 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 9 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6952336&loc=d3e14557-108349 + Details
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- Definition The amount of cash paid for the settlement of litigation or for other legal issues during the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 25 -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3536-108585 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 27 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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. + Details
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