Application to Sell Power Plant Projects, Number

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Amount classified as assets attributable to disposal group held for sale or disposed of.

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Amount after tax of gain (loss) not previously recognized resulting from the disposal of a discontinued operation.

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Amount before tax of income (loss) from a discontinued operation. Includes, but is not limited to, the income (loss) from operations during the phase-out period, gain (loss) on disposal, gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and adjustments to a prior period gain (loss) on disposal.

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Amount classified as goodwill attributable to disposal group held for sale or disposed of.

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Amount of revenue attributable to disposal group, including, but not limited to, discontinued operation.

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The cash inflow from the sale of property, plant and equipment (capital expenditures), software, and other intangible assets.

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Discontinued Operations (Details) $ in Millions		12 Months Ended
Discontinued Operations (Details) $ in Millions	Feb. 12, 2014 USD ($) plant	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from asset sales	$ 394	$ 15	$ 20	$ 394
Assets held-for-sale	235
Goodwill	29
Pre-tax income				155
Pre-tax gain on sale of assets				142
Revenue				5
FES
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from asset sales	307	$ 9	$ 13	307
Assets held-for-sale	122
Goodwill	$ 1
Pre-tax income				186
Pre-tax gain on sale of assets				177
Revenue				$ 5
FERC \| Hydroelectric Asset Sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Application to sell power plant projects, number \| plant	11