Number of amicus briefs favorable to our co-defendants filed.

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Number of manufactured gas plant sites where remediation is complete, other than ongoing operations.

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Number of sites that may require remediation

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Number of sites where the company believes it has no liability.

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Total costs accrued as of the balance sheet date for environmental loss contingencies.

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Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

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Amount of rent expense incurred for leased assets, including but not limited to, furniture and equipment, that is not directly or indirectly associated with the manufacture, sale or creation of a product or product line.

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No definition available.

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Number of pending claims pertaining to a loss contingency.

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Amount of required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Minimum amount of purchase arrangement maturing after the fifth fiscal year following the latest fiscal year. Includes, but not limited to, recorded and unrecorded purchase obligations, long-term purchase commitments, and short-term purchase commitments.

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Minimum amount of purchase arrangement maturing in the fifth fiscal year following the latest fiscal year. Includes, but not limited to, recorded and unrecorded purchase obligations, long-term purchase commitments, and short-term purchase commitments.

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Minimum amount of purchase arrangement maturing in the fourth fiscal year following the latest fiscal year. Includes, but not limited to, recorded and unrecorded purchase obligations, long-term purchase commitments, and short-term purchase commitments.

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Minimum amount of purchase arrangement maturing in the next fiscal year following the latest fiscal year. Includes, but not limited to, recorded and unrecorded purchase obligations, long-term purchase commitments, and short-term purchase commitments.

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Minimum amount of purchase arrangement maturing in the second fiscal year following the latest fiscal year. Includes, but not limited to, recorded and unrecorded purchase obligations, long-term purchase commitments, and short-term purchase commitments.

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Minimum amount of purchase arrangement maturing in the third fiscal year following the latest fiscal year. Includes, but not limited to, recorded and unrecorded purchase obligations, long-term purchase commitments, and short-term purchase commitments.

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Recorded amount of the individual components comprising the asset for third-party recoveries related to environmental remediation obligations.

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Estimated time frame for resolution of the uncertainty as to the loss for an individual site.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 30

-Section 50

-Paragraph 10

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Commitments and Contingencies (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract]
2015	$ 5
2016	4
2017	3
2018	2
2019	1
2020 and beyond	6
Total	21
Total lease expense for all operating leases	9us-gaap_LeaseAndRentalExpense	20us-gaap_LeaseAndRentalExpense	26us-gaap_LeaseAndRentalExpense
GenOn Demand Charges Transportation Contracts [Member]
Legal, Environmental and Other Regulatory Matters [Abstract]
Guarantor Obligations, Maximum Exposure, Undiscounted	42
Enable Guaranteed Senior Notes [Member]
Legal, Environmental and Other Regulatory Matters [Abstract]
Guarantor Obligations, Maximum Exposure, Undiscounted	1,100
Minnesota Service Territory [Member]
Legal, Environmental and Other Regulatory Matters [Abstract]
Site Contingency Number Of Sites	7
Site Contingency Sites Without Liability	2
Site Contingency Completed Remediation	2
Accrual for Environmental Loss Contingencies	7
Recorded Third-Party Environmental Recoveries, Amount	4
Minnesota Service Territory [Member] \| Minimum [Member]
Legal, Environmental and Other Regulatory Matters [Abstract]
Site Contingency Loss Exposure	5
Site Contingency, Estimated Time Frame to Resolve Contingency	30
Minnesota Service Territory [Member] \| Maximum [Member]
Legal, Environmental and Other Regulatory Matters [Abstract]
Site Contingency Loss Exposure	29
Site Contingency, Estimated Time Frame to Resolve Contingency	50
Gas Market Manipulation Cases [Member]
Legal, Environmental and Other Regulatory Matters [Abstract]
Loss Contingency, Pending Claims, Number	1
Loss Contingency, Amicus Briefs filed, number	4
Natural Gas Supply Commitments [Member]
Long-term Purchase Commitment [Line Items]
2015	696
2016	605
2017	551
2018	507
2019	255
After 2019	$ 114