Taxes (Details 2) - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014
Accumulated deferred income taxes
Property basis differences	$ 9,920	$ 9,354
Deferred sale and leaseback gain	(360)	(381)
Pension and OPEB	(1,541)	(1,433)
Nuclear decommissioning activities	480	458
Asset retirement obligations	(731)	(641)
Regulatory asset/liability	763	768
Loss carryforwards and AMT credits	(1,965)	(1,932)
Loss carryforward valuation reserve	192	174
All other	15	172
Net deferred income tax liability	6,773	6,539
FES
Accumulated deferred income taxes
Property basis differences	1,901	1,749
Deferred sale and leaseback gain	(342)	(356)
Pension and OPEB	(393)	(373)
Lease market valuation liability	95	75
Nuclear decommissioning activities	483	489
Asset retirement obligations	(509)	(486)
Loss carryforwards and AMT credits	(687)	(631)
Loss carryforward valuation reserve	46	32
All other	6	(15)
Net deferred income tax liability	$ 600	$ 484

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 forward valuation reserve.

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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 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 and deferred tax liability, of deferred tax asset attributable to deductible differences and carryforwards, netted by jurisdiction and classified as noncurrent.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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