Counterparties representing 10% or more (Details)	Dec. 31, 2014	Dec. 31, 2013
Assets from price risk management activities:
Counterparty A	63.00%por_CounterpartyA	53.00%por_CounterpartyA
Counterparty B	14.00%por_CounterpartyB	6.00%por_CounterpartyB
Concentration of Risk, Derivative Instruments, Assets	77.00%	59.00%
Liabilities from price risk management activities: [Abstract]
Counterparty C	22.00%por_CounterpartyF	43.00%por_CounterpartyF
Counterparty D	12.00%por_CounterpartyGPrmLiabilities	11.00%por_CounterpartyGPrmLiabilities
Concentration of Risk, Derivative Instruments, Liabilities	34.00%	54.00%

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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

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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 liabilities arising from derivative instruments from price risk management activities.

+ References

No definition available.

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- Definition

Counterparty G PRM Liabilities

+ References

No definition available.

+ Details

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