Price Risk Management Counterparties Representing 10% or More (Details)	Mar. 31, 2014	Dec. 31, 2013
Assets from price risk management activities:
Counterparty A	20.00%	5.00%
Counterparty B	18.00%	53.00%
Counterparty C	15.00%	6.00%
Counterparty D	10.00%	5.00%
Concentration of Risk, Derivative Instruments, Assets	63.00%	69.00%
Liabilities from price risk management activities:
Counterparty E	46.00%	43.00%
Counterparty F	12.00%	11.00%
Concentration of Risk, Derivative Instruments, Liabilities	58.00%	54.00%

- Details

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- Definition

Represents aggregate of individually significant counterparties of total assets arising from derivative instruments from price risk management activities.

+ References

No definition available.

+ Details

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- Definition

Represents aggregate of individually significant counterparties of total liabilities arising from derivative instruments from price risk management activities.

+ References

No definition available.

+ Details

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- Definition

Individually significant counterparty of total assets arising from derivative instruments from price risk management activities.

+ References

No definition available.

+ Details

Name:	por_CounterpartyA
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- Definition

Individually significant counterparty of total assets arising from derivative instruments from price risk management activities.

+ References

No definition available.

+ Details

Name:	por_CounterpartyB
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- Definition

Individually significant counterparty of total assets arising from derivative instruments from price risk management activities.

+ References

No definition available.

+ Details

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- Definition

Individually significant counterparty of total assets arising from dreivative instruments from price risk management activities.

+ References

No definition available.

+ Details

Name:	por_CounterpartyD
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- Definition

Counterparty E For PRM Liab

+ References

No definition available.

+ Details

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- Definition

Individually significant counterparty of total liabilities arising from derivative instruments from price risk management activities.

+ References

No definition available.

+ Details

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- Details

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