XML 20 R27.htm IDEA: XBRL DOCUMENT
v2.4.0.8

Basis of Presentation (Details) (USD $) | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | ---
Sep. 30, 2013 retail_customers | Sep. 30, 2012 | Sep. 30, 2013 retail_customers | Sep. 30, 2012 | Dec. 31, 2011 | Dec. 31, 2010 | Dec. 31, 2009
Basis of Presentation [Abstract] |  |  |  |  |  |  |
Number of Retail Customers | 835,540 |  | 835,540 |  |  |  |
Decoupling Mechanism Deferrals, Net |  | $ 1,000,000 | $ (5,000,000) | $ 1,000,000 |  |  |
Contribution to the voluntary employees’ beneficiary association trust |  |  |  | 2,000,000 |  |  |
Renewable adjustment clause deferrals |  |  |  | 1,000,000 |  |  |
Other Comprehensive Income | 0 | 0 | 0 | 0 |  |  |
revenue overstatment | $ 9,000,000 |  |  | $ 3,000,000 | $ 3,000,000 | $ 2,000,000 | $ 1,000,000

X
- Details
Name: | por_BasisOfPresentationAbstract
Namespace Prefix: | por_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The amount of cash or cash equivalents contributed during the reporting period by the entity to fund its non-pension postretirement benefit plans. + References No definition available. + Details
Name: | por_ContributionToVoluntaryEmployeesBeneficiaryAssociationTrust
Namespace Prefix: | por_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition The deferral, which can be either a positive or negaitive amount depending on whether a collection from or refund to customers results, of the amounts recorded in net income for energy useage by customers on a weather adjusted basis that is different from base rates as determined under the Company's decoupling mechanism, expected to be recovered or refunded in future periods. + References No definition available. + Details
Name: | por_DecouplingMechanismDeferralsNet
Namespace Prefix: | por_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Includes residential, commercial and industrial. + References No definition available. + Details
Name: | por_NumberOfRetailCustomers
Namespace Prefix: | por_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Definition The deferral under the Company's Renewable Adjustment Clause mechanism of the amounts recorded in net income related to the Company's renewable energy projects that are expected to be recovered, or refunded, in future periods. + References No definition available. + Details
Name: | por_RenewableAdjustmentClauseDeferrals
Namespace Prefix: | por_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Adjustment to revenue to reduce total for the overstatment of a prior customer billing. + References No definition available. + Details
Name: | por_Revenueoverstatment
Namespace Prefix: | por_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount after tax of other comprehensive income (loss) attributable to parent entity. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 45 -Paragraph 20 -URI http://asc.fasb.org/extlink&oid=7656940&loc=SL4569643-111683 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 45 -Paragraph 19 -URI http://asc.fasb.org/extlink&oid=7656940&loc=SL4569616-111683 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 50 -Paragraph 1A -Subparagraph (c)(3) -URI http://asc.fasb.org/extlink&oid=18733093&loc=SL4573702-111684 + Details
Name: | us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration