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Contingencies (Details) - USD ($) | 3 Months Ended | 12 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | ---
Mar. 31, 2016 | Dec. 31, 1997 | Jun. 30, 2016 | Dec. 31, 2015 | Sep. 30, 2008 | Dec. 31, 1993
Loss Contingencies [Line Items] |  |  |  |  |  |
Investment in Trojan |  |  |  |  |  | 87.00%
Refund to customers for Trojan Investment including interest |  |  |  |  | $ 33,000,000 |
Class action damages sought | $ 260,000,000 |  |  |  |  |
Site Contingency, Names of Other Potentially Responsible Parties | 100 | 69 |  |  |  |
Remediation cost estimate lower range |  |  | $ 746,000,000 | $ 1,500,000,000 |  |
Civil Penalty Claim - Per day per violation through January 12, 2009 | $ 32,500 |  |  |  |  |
Civil Penalty Claim - Per day per violation after January 12, 2009 | $ 37,500 |  |  |  |  |

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- Definition Civil Penalty Claim - Per day per violation after January 12, 2009 + References No definition available. + Details
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- Definition Civil Penalty Claim - Per Day Per Violation through January 12, 2009 + References No definition available. + Details
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- Definition Class action lawsuit damages sought by plaintiffs against the Company. + References No definition available. + Details
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- Definition The portion of the Company's remaining investment in its Trojan plant that the OPUC allowed the Company to recover. + References No definition available. + Details
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- Definition refund to customers for Trojan Investment including interest + References No definition available. + Details
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- Definition The estimated minimum amount of possible loss from the contingency. + References Reference 1: 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=25496072&loc=d3e14435-108349 Reference 2: 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=25496072&loc=d3e14557-108349 + Details
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- Definition Names of other potentially responsible parties for an individual site. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 410 -SubTopic 30 -Section 50 -Paragraph 10 -Subparagraph (d)(3) -URI http://asc.fasb.org/extlink&oid=6393242&loc=d3e13237-110859 + Details
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