Price Risk Management Counterparties Representing 10% or More (Details)	Sep. 30, 2012	Dec. 31, 2011
Assets from price risk management activities:
Counterparty A	15.00%	19.00%
Counterparty B	12.00%	2.00%
Counterparty C	11.00%	16.00%
Counterparty D	6.00%	13.00%
Concentration of Risk, Derivative Instruments, Assets	44.00%	50.00%
Liabilities from price risk management activities:
Counterparty E	22.00%	23.00%
Counterparty F	13.00%	10.00%
Concentration of Risk, Derivative Instruments, Liabilities	35.00%	33.00%

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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.

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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 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

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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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- 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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