Taxes (Details 2) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Accumulated deferred income taxes
Property basis differences	$ 9,354	$ 8,734
Deferred sale and leaseback gain	(381)	(401)
Pension and OPEB	(1,433)	(972)
Nuclear decommissioning activities	458	460
Asset retirement obligations	(641)	(651)
Regulatory asset/liability	768	750
Loss carryforwards and AMT credits	(1,932)	(1,598)
Loss carryforward valuation reserve	174	125
All other	172	155
Net deferred income tax liability	6,539	6,602
FES
Accumulated deferred income taxes
Property basis differences	1,749	1,354
Deferred sale and leaseback gain	(356)	(370)
Pension and OPEB	(373)	(66)
Lease market valuation liability	75	54
Nuclear decommissioning activities	489	470
Asset retirement obligations	(486)	(439)
Loss carryforwards and AMT credits	(631)	(354)
Loss carryforward valuation reserve	32	27
All other	(15)	40
Net deferred income tax liability	$ 484	$ 716

Deferred Tax Assets Liabilities, Net, Asset Retirement Obligation Liability

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Deferred Tax Assets Liabilities Net Non current All other.

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Deferred Tax Assets Liabilities Net Non current Deferred sale and leaseback gain.

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Deferred Tax Assets Liabilities Net Non current Lease market valuation liability.

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Deferred Tax Assets Liabilities Net Non current Loss carry forwards and Tax Credits

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Deferred Tax Assets Liabilities Net Non current Loss carry forward valuation reserve.

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Deferred Tax Assets Liabilities Net Non current Nuclear decommissioning activities.

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Deferred Tax Assets Liabilities Net Non current Pension and other postretirement obligations.

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Deferred Tax Assets Liabilities Net Non current Property basis differences.

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Deferred Tax Assets Liabilities, Net, Regulatory Asset Liability

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Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards, net of deferred tax liability attributable to taxable temporary differences expected to be realized or consumed after one year (or the normal operating cycle, if longer).

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

-Publisher FASB

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