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Regulatory Assets and Liabilities Regulatory Assets and Liabilities (Policies) | 12 Months Ended
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Dec. 31, 2011
Regulatory Assets and Liabilities [Abstract] |
Description of Impairment to Carrying Amount of Regulatory Assets | During the fourth quarter of 2011, PGE received an order from the OPUC on its Annual Update Tariff for 2012 net variable power costs (NVPC). Pursuant to the order, the OPUC reduced the Company’s 2012 NVPC forecast by approximately $3 million, which is reflected as a reduction to the regulatory asset for price risk management as of December 31, 2011.
Refund Period Not Yet Determined for REgulatory Liabilities, PCAM and Pollution Control Tax Credits | Refund period not yet determined
Remaining Recovery Period of Regulatory Asset, Pension and Postretirement Plans, For Which No Return on Investment During Recovery is Provided | Recovery expected over the average service life of employees
Remaining Refund Period of Regulatory Liabilities, Asset Removal Costs and Retirement Obligations | Recovery expected over the estimated lives of the assets

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- Definition Refund Period Not Yet Determined for REgulatory Liabilities, PCAM and Pollution Control Tax Credits + References No definition available. + Details
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- Definition Remaining Recovery Period of Regulatory Asset, Pension and Postretirement Plans, For Which No Return on Investment During Recovery is Provided + References No definition available. + Details
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- Definition Describes any reduction to the carrying amounts of regulated assets that result from impairment (for example, rate actions of a regulator). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 980 -SubTopic 360 -Section 35 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=6500292&loc=d3e45799-110387 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 90 -Paragraph 7 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 71 -Paragraph 10 -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 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 980 -SubTopic 340 -Section 35 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6066304&loc=d3e44026-110379 + Details
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