XML 18 R70.htm IDEA: XBRL DOCUMENT
v2.4.0.6

Price Risk Management Schedule of Concentration of Risk, by Counterparty (Details) | Dec. 31, 2011 | Dec. 31, 2010
--- | --- | ---
Assets from price risk management activities: |  |
Counterparty A | 19.00% | 1.00%
Counterparty B | 16.00% | 1.00%
Counterparty C | 13.00% | 5.00%
Counterparty D | 7.00% | 22.00%
Counterparty E | 7.00% | 23.00%
Counterparty F | 0.00% | 11.00%
Counterparty G | 0.00% | 10.00%
Concentration of Risk, Derivative Instruments, Assets | 62.00% | 73.00%
Liabilities from price risk management activities: [Abstract] |  |
Counterparty E | 23.00% | 24.00%
Counterparty H | 10.00% | 4.00%
Counterparty I | 7.00% | 12.00%
Concentration of Risk, Derivative Instruments, Liabilities | 40.00% | 40.00%

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

X
- Definition Represents aggregate of individually significant counterparties of total assets arising from derivative instruments from price risk management activities. + References No definition available. + Details
Name: | por_ConcentrationOfRiskDerivativeInstrumentsAssets
Namespace Prefix: | por_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Represents aggregate of individually significant counterparties of total liabilities arising from derivative instruments from price risk management activities. + References No definition available. + Details
Name: | por_ConcentrationOfRiskDerivativeInstrumentsLiabilities
Namespace Prefix: | por_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Individually significant counterparty of total assets arising from derivative instruments from price risk management activities. + References No definition available. + Details
Name: | por_CounterpartyA
Namespace Prefix: | por_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Individually significant counterparty of total assets arising from derivative instruments from price risk management activities. + References No definition available. + Details
Name: | por_CounterpartyB
Namespace Prefix: | por_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Individually significant counterparty of total assets arising from derivative instruments from price risk management activities. + References No definition available. + Details
Name: | por_CounterpartyC
Namespace Prefix: | por_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Individually significant counterparty of total assets arising from dreivative instruments from price risk management activities. + References No definition available. + Details
Name: | por_CounterpartyD
Namespace Prefix: | por_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Individually significant counterparty of total assets arising from derivative instruments from price risk management activities. + References No definition available. + Details
Name: | por_CounterpartyE
Namespace Prefix: | por_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Individually significant counterparty of total liabilities arising from derivative instruments from price risk management activities. + References No definition available. + Details
Name: | por_CounterpartyEForPrmLiabs
Namespace Prefix: | por_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Individually significant counterparty of total assets arising from derivative instruments from price risk management activities. + References No definition available. + Details
Name: | por_CounterpartyFForPrmAssets
Namespace Prefix: | por_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Individually significant counterparty of total assets arising from derivative instruments from price risk management activities. + References No definition available. + Details
Name: | por_CounterpartyGForPrmAssets
Namespace Prefix: | por_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Individually significant counterparty of total liabilities arising from derivative instruments from price risk management activities. + References No definition available. + Details
Name: | por_CounterpartyHForPrmLiabs
Namespace Prefix: | por_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Individually significant counterparty of total liabilities arising from derivative instruments from price risk management activities. + References No definition available. + Details
Name: | por_CounterpartyIForPrmLiabs
Namespace Prefix: | por_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

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