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v3.6.0.2

Consolidated Statements of Comprehensive Income Consolidated Statement of Comprehensive Income Parentheticals $ in Millions | 12 Months Ended
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Dec. 31, 2014 USD ($)
Net Taxes on change in compensation retirement benefits liability and amortization | $ 2

X
- Definition Net Taxes on change in compensation retirement benefits liability and amortization + References No definition available. + Details
Name: | por_NetTaxesOnChangeInCompensationRetirementBenefitsLiabilityAndAmortization
Namespace Prefix: | por_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration