New Financing Abstract.

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Redemptions And Repayments Abstract.

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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The increase (decrease) in cash associated with the entity's continuing operating, investing, and financing activities. While for technical reasons this element has no balance attribute, the default assumption is a debit balance consistent with its label.

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No definition available.

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Amount of cash inflow (outflow) from financing activities, including discontinued operations. Financing activity cash flows include obtaining resources from owners and providing them with a return on, and a return of, their investment; borrowing money and repaying amounts borrowed, or settling the obligation; and obtaining and paying for other resources obtained from creditors on long-term credit.

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Amount of cash inflow (outflow) from investing activities, including discontinued operations. Investing activity cash flows include making and collecting loans and acquiring and disposing of debt or equity instruments and property, plant, and equipment and other productive assets.

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Amount of cash inflow (outflow) from operating activities, including discontinued operations. Operating activity cash flows include transactions, adjustments, and changes in value not defined as investing or financing activities.

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Cash outflow associated with the purchase of any material that is commonly used in the generation of nuclear energy.

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No definition available.

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Amount of cash (inflow) outflow from investing activities classified as other.

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The cash outflow to acquire debt and equity securities not classified as either held-to-maturity securities or trading securities which would be classified as available-for-sale securities and reported at fair value, with unrealized gains and losses excluded from earnings and reported in a separate component of shareholders' equity.

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The cash outflow for purchases of and capital improvements on property, plant and equipment (capital expenditures), software, and other intangible assets.

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The cash inflow from a debt initially having maturity due after one year or beyond the operating cycle, if longer.

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The cash inflow or outflow associated with long-term loans for related parties where one party can exercise control or significant influence over another party, including affiliates, owners or officers and their immediate families, pension trusts, and so forth. Alternate caption: Proceeds from (Payments for) Advances to Affiliates.

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Amount of cash inflow (outflow) from financing activities classified as other.

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The cash inflow associated with the sale of debt and equity securities classified as available-for-sale securities.

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The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

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Supplemental Guarantor Information (Details 2) - USD ($) $ in Millions	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Consolidated Statements of Cash Flows [Abstract]
NET CASH (USED FOR) PROVIDED FROM OPERATING ACTIVITIES			$ 2,762	$ 2,592
New Financing-
Long-term debt			4,050	521
Short-term borrowings, net			0	1,275
Redemptions and Repayments-
Long-term debt			(1,711)	(1,017)
Other			(67)	(17)
Net cash (used for) provided from financing activities			(381)	304
CASH FLOWS FROM INVESTING ACTIVITIES:
Property additions	$ (593)	$ (664)	(1,847)	(2,156)
Nuclear fuel			(156)	(195)
Sales of investment securities held in trusts			1,923	1,361
Purchases of investment securities held in trusts			(1,995)	(1,437)
Other			24	52
Net cash used for investing activities			(2,181)	(2,476)
Net change in cash and cash equivalents			200	420
Cash and cash equivalents at beginning of period			199	131	$ 131
Cash and cash equivalents at end of period	399	551	399	551	199
Eliminations
Consolidated Statements of Cash Flows [Abstract]
NET CASH (USED FOR) PROVIDED FROM OPERATING ACTIVITIES			(13)	(12)
New Financing-
Long-term debt				0
Short-term borrowings, net			(259)	(692)
Redemptions and Repayments-
Long-term debt			13	12
Other			0	0
Net cash (used for) provided from financing activities			(246)	(680)
CASH FLOWS FROM INVESTING ACTIVITIES:
Property additions			0	0
Nuclear fuel			0	0
Sales of investment securities held in trusts			0	0
Purchases of investment securities held in trusts			0	0
Loans to affiliated companies, net			259	692
Other			0	0
Net cash used for investing activities			259	692
Net change in cash and cash equivalents			0	0
Cash and cash equivalents at beginning of period			0	0	0
Cash and cash equivalents at end of period	0	0	0	0	0
FES
Consolidated Statements of Cash Flows [Abstract]
NET CASH (USED FOR) PROVIDED FROM OPERATING ACTIVITIES			(463)	(605)
New Financing-
Long-term debt				0
Short-term borrowings, net			330	701
Redemptions and Repayments-
Long-term debt			0	0
Other			0	0
Net cash (used for) provided from financing activities			330	701
CASH FLOWS FROM INVESTING ACTIVITIES:
Property additions			(1)	(28)
Nuclear fuel			0	0
Sales of investment securities held in trusts			0	0
Purchases of investment securities held in trusts			0	0
Loans to affiliated companies, net			137	(87)
Other			(3)	19
Net cash used for investing activities			133	(96)
Net change in cash and cash equivalents			0	0
Cash and cash equivalents at beginning of period			0	0	0
Cash and cash equivalents at end of period	0	0	0	0	0
FG
Consolidated Statements of Cash Flows [Abstract]
NET CASH (USED FOR) PROVIDED FROM OPERATING ACTIVITIES			387	402
New Financing-
Long-term debt				186
Short-term borrowings, net			14	92
Redemptions and Repayments-
Long-term debt			(171)	(211)
Other			(5)	(6)
Net cash (used for) provided from financing activities			(162)	61
CASH FLOWS FROM INVESTING ACTIVITIES:
Property additions			(46)	(171)
Nuclear fuel			0	0
Sales of investment securities held in trusts			0	0
Purchases of investment securities held in trusts			0	0
Loans to affiliated companies, net			(179)	(292)
Other			0	0
Net cash used for investing activities			(225)	(463)
Net change in cash and cash equivalents			0	0
Cash and cash equivalents at beginning of period			2	2	2
Cash and cash equivalents at end of period	2	2	2	2	2
NG
Consolidated Statements of Cash Flows [Abstract]
NET CASH (USED FOR) PROVIDED FROM OPERATING ACTIVITIES			547	820
New Financing-
Long-term debt				285
Short-term borrowings, net			0	0
Redemptions and Repayments-
Long-term debt			(5)	(304)
Other			0	(2)
Net cash (used for) provided from financing activities			(5)	(21)
CASH FLOWS FROM INVESTING ACTIVITIES:
Property additions			(154)	(233)
Nuclear fuel			(156)	(195)
Sales of investment securities held in trusts			834	576
Purchases of investment securities held in trusts			(878)	(619)
Loans to affiliated companies, net			(188)	(328)
Other			0	0
Net cash used for investing activities			(542)	(799)
Net change in cash and cash equivalents			0	0
Cash and cash equivalents at beginning of period			0	0	0
Cash and cash equivalents at end of period	0	0	0	0	0
Consolidated
Consolidated Statements of Cash Flows [Abstract]
NET CASH (USED FOR) PROVIDED FROM OPERATING ACTIVITIES			458	605
New Financing-
Long-term debt			0	471
Short-term borrowings, net			85	101
Redemptions and Repayments-
Long-term debt			(163)	(503)
Other			(5)	(8)
Net cash (used for) provided from financing activities			(83)	61
CASH FLOWS FROM INVESTING ACTIVITIES:
Property additions			(201)	(432)
Nuclear fuel			(156)	(195)
Sales of investment securities held in trusts			834	576
Purchases of investment securities held in trusts			(878)	(619)
Loans to affiliated companies, net			29	(15)
Other			(3)	19
Net cash used for investing activities			(375)	(666)
Net change in cash and cash equivalents			0	0
Cash and cash equivalents at beginning of period			2	2	2
Cash and cash equivalents at end of period	$ 2	$ 2	$ 2	$ 2	$ 2