Debt Instruments, Number of Debt Series

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- Definition

Minimum Equity To Total Capitalization Ratio To Be Maintained For Payment Of Capital Dividend

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- Definition

Number Of Subsidiaries That Issued Environmental Control Bonds

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Preference Stock Shares Outstanding.

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- Definition

Principal Default Amount Specified In Debt Covenants.

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- Definition

Amount paid to settle bankruptcy claim.

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- Definition

Aggregate dividends paid during the period for each share of common stock outstanding.

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Aggregate dividends declared during the period for each share of common stock outstanding.

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Face amount or stated value per share of common stock.

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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Aggregate par or stated value of issued nonredeemable common stock (or common stock redeemable solely at the option of the issuer). This item includes treasury stock repurchased by the entity. Note: elements for number of nonredeemable common shares, par value and other disclosure concepts are in another section within stockholders' equity.

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- Definition

All amounts that, per contract, are due to the servicer in exchange for servicing the financial asset and would no longer be received by a servicer if the beneficial owners of the serviced assets (or their trustees or agents) were to exercise their actual or potential authority under the contract to shift the servicing to another servicer. Depending on the servicing contract, those fees may include some or all of the difference between the interest rate collected on the asset being serviced and the rate to be paid to the beneficial owners of the asset.

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The number of shares converted in a noncash (or part noncash) transaction. Noncash is defined as transactions during a period that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

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The number of new shares issued in the conversion of stock in a noncash (or part noncash) transaction. Noncash is defined as transactions during a period that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

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Face (par) amount of debt instrument at time of issuance.

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Contractual interest rate for funds borrowed, under the debt agreement.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Period between issuance and maturity of long-term debt, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Represents the current and noncurrent portions of a debt security issued by a state, certain agencies or authorities, a local government, or development corporation to finance the construction of air- or water-pollution control facilities or sewage or solid waste disposal facilities pursuant to federal law. The bonds are backed by the credit of the beneficiary of the financing rather than the credit of the issuer.

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Long-Term transition bonds are bonds under the Competition Act in which the proceeds of Transition Bonds are required to be used principally to reduce qualified stranded costs and the related capitalization of the utility. This represents the current and noncurrent portions. The initial maturity is beyond one year or beyond the normal operating cycle, if longer.

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Face amount or stated value per share of preferred stock nonredeemable or redeemable solely at the option of the issuer.

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Total number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) issued to shareholders (includes related preferred shares that were issued, repurchased, and remain in the treasury). May be all or portion of the number of preferred shares authorized. Excludes preferred shares that are classified as debt.

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Aggregate share number for all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by stockholders. Does not include preferred shares that have been repurchased.

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Aggregate par or stated value of issued nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer). This item includes treasury stock repurchased by the entity. Note: elements for number of nonredeemable preferred shares, par value and other disclosure concepts are in another section within stockholders' equity.

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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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The cumulative amount of the reporting entity's undistributed earnings or deficit.

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Number of shares issued during the period to an employee benefit plan, such as a defined contribution or defined benefit plan.

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CAPITALIZATION - Narrative (Details)				3 Months Ended								12 Months Ended
CAPITALIZATION - Narrative (Details)	Dec. 15, 2020 $ / shares	Apr. 20, 2020 USD ($)	Feb. 20, 2020 USD ($) series	Dec. 31, 2020 USD ($) $ / shares shares	Sep. 30, 2020 $ / shares	Jun. 30, 2020 $ / shares	Mar. 31, 2020 USD ($) $ / shares	Dec. 31, 2019 USD ($) $ / shares shares	Sep. 30, 2019 $ / shares	Jun. 30, 2019 $ / shares	Mar. 31, 2019 $ / shares	Dec. 31, 2020 USD ($) subsidiary $ / shares shares	Dec. 31, 2019 USD ($) $ / shares shares	Dec. 31, 2018 USD ($) $ / shares shares	Jul. 20, 2020 USD ($)	Jun. 29, 2020 USD ($)	Jun. 08, 2020 USD ($) series	Feb. 27, 2020 USD ($)	Jan. 31, 2018 USD ($) $ / shares shares	Jan. 22, 2018 USD ($) $ / shares shares	Jun. 30, 2013 USD ($)
Debt Instrument [Line Items]
Retained earnings (accumulated deficit)				$ (2,888,000,000)				$ (3,967,000,000)				$ (2,888,000,000)	$ (3,967,000,000)
Dividends declared (in dollars per share) \| $ / shares	$ 0.39											$ 1.56	$ 1.53	$ 1.82
Common stock dividends per share paid, in dollars per share \| $ / shares				$ 0.39	$ 0.39	$ 0.39	$ 0.39	$ 0.38	$ 0.38	$ 0.38	$ 0.38
FERC-defined equity to total capitalization ratio												35.00%
Common stock, par value (in dollars per share) \| $ / shares				$ 0.10				$ 0.10				$ 0.10	$ 0.10
Amount of private placement																				$ 850,000,000
Preferred shares, outstanding (in shares) \| shares				0				0				0	0
Preference shares outstanding (in shares) \| shares				0				0				0	0
Transition bond outstanding				$ 9,000,000				$ 25,000,000				$ 9,000,000	$ 25,000,000
Preferred stock, par value (in dollars per share) \| $ / shares				$ 100								$ 100
Repayments of debt												$ 1,114,000,000	789,000,000	$ 2,608,000,000
Number of subsidiaries that issued environmental control bonds \| subsidiary												2
Environmental control bonds outstanding				$ 300,000,000				333,000,000				$ 300,000,000	$ 333,000,000
2021				132,000,000								132,000,000
Principal default amount specified in debt covenants												$ 100,000,000
Common Stock Purchase Agreement
Debt Instrument [Line Items]
Amount of shares issued \| shares																				30,120,482
Common stock, par value (in dollars per share) \| $ / shares																				$ 0.10
Registered Shareholders, Directors and Employees of Subsidiaries
Debt Instrument [Line Items]
Stock Investment Plan and certain share-based benefit plans (in shares) \| shares												2,000,000	3,000,000	3,200,000
Series A Convertible Preferred Stock
Debt Instrument [Line Items]
Preferred stock shares issued (in shares) \| shares																			1,616,000
Preferred stock, par value (in dollars per share) \| $ / shares																			$ 100
Amount of preferred stock investment																			$ 1,620,000,000
Phase In Recovery Bonds
Debt Instrument [Line Items]
Long-term debt and other long-term obligations				245,000,000				$ 268,000,000				$ 245,000,000	$ 268,000,000
Senior Notes \| $750 Million Senior Unsecured Notes
Debt Instrument [Line Items]
Face amount of loan																	$ 750,000,000
Number of debt series \| series																	2
Senior Notes \| 1.60% Senior A Notes Due 2026
Debt Instrument [Line Items]
Face amount of loan																	$ 300,000,000
Interest rate (percent)																	1.60%
Senior Notes \| 2.250% Senior B Notes Due 2030
Debt Instrument [Line Items]
Face amount of loan																	$ 450,000,000
Interest rate (percent)																	2.25%
Senior Notes \| $1.75 Billion Senior Notes
Debt Instrument [Line Items]
Face amount of loan			$ 1,750,000,000
Number of debt series \| series			3
Senior Notes \| 2.050% Series A Senior Notes Due 2025
Debt Instrument [Line Items]
Face amount of loan			$ 300,000,000
Interest rate (percent)			2.05%
Senior Notes \| 2.650% Series B Senior Notes Due 2030
Debt Instrument [Line Items]
Face amount of loan			$ 600,000,000
Interest rate (percent)			2.65%
Senior Notes \| 3.400% Series C Senior Notes Due 2050
Debt Instrument [Line Items]
Face amount of loan			$ 850,000,000
Interest rate (percent)			3.40%
Term Loan \| $750M Term Loan
Debt Instrument [Line Items]
Repayments of debt			$ 750,000,000
Debt term			2 years
Term Loan \| $1B Term Loan
Debt Instrument [Line Items]
Face amount of loan			$ 1,000,000,000
Repayments of debt			$ 250,000,000
Debt term			364 days
Common Stock
Debt Instrument [Line Items]
Stock Investment Plan and certain share-based benefit plans (in shares) \| shares												2,000,000	3,000,000	4,000,000
Amount of private placement																				$ 3,000,000
Number of shares issued \| shares													25,696,168	33,238,910
Preferred Stock
Debt Instrument [Line Items]
Number of shares converted \| shares													704,589	911,411
Preferred Stock \| Series A Convertible Preferred Stock
Debt Instrument [Line Items]
Amount of preferred stock investment																			162,000,000
OPIC
Debt Instrument [Line Items]
Amount of private placement																				$ 847,000,000
OPIC \| Series A Convertible Preferred Stock
Debt Instrument [Line Items]
Amount of preferred stock investment																			$ 1,460,000,000
PN \| Senior Notes
Debt Instrument [Line Items]
Face amount of loan		$ 125,000,000
PN \| Senior Notes \| 3.61% Senior Unsecured Notes Due 2032
Debt Instrument [Line Items]
Interest rate (percent)		3.61%
PN \| Senior Notes \| 3.71% Senior Notes Due 2035
Debt Instrument [Line Items]
Interest rate (percent)		3.71%
Repayments of debt		$ 125,000,000
PN \| Senior Notes \| 5.20% Senior Notes Due 2020
Debt Instrument [Line Items]
Face amount of loan		$ 250,000,000
Interest rate (percent)		5.20%
MP \| PCRB
Debt Instrument [Line Items]
2021				$ 74,000,000								$ 74,000,000
MAIT \| Senior Notes \| 3.60 Percent Senior Notes Due 2032
Debt Instrument [Line Items]
Face amount of loan							$ 125,000,000
Interest rate (percent)							3.60%
MAIT \| Senior Notes \| 3.70% Senior Notes Due 2035
Debt Instrument [Line Items]
Face amount of loan							$ 125,000,000
Interest rate (percent)							3.70%
PE \| FMBs \| 2.67% First Mortgage Bond Due 2032
Debt Instrument [Line Items]
Face amount of loan																$ 75,000,000
Interest rate (percent)																2.67%
PE \| FMBs \| 3.43% First Mortgage Bonds Due 2051
Debt Instrument [Line Items]
Face amount of loan																$ 100,000,000
Interest rate (percent)																3.43%
CEI \| Senior Notes \| 2.77% Senior Notes Due 2034
Debt Instrument [Line Items]
Face amount of loan															$ 150,000,000
Interest rate (percent)															2.77%
CEI \| Senior Notes \| 3.23% Senior Notes Due 2040
Debt Instrument [Line Items]
Face amount of loan															$ 100,000,000
Interest rate (percent)															3.23%
FES \| FES Key Creditor Groups \| Affiliates
Debt Instrument [Line Items]
Amount paid to settle claims			$ 853,000,000
FES \| IT Access Agreement \| Affiliates
Debt Instrument [Line Items]
Amount paid to settle claims			$ 125,000,000															$ 125,000,000
Ohio Funding Companies
Debt Instrument [Line Items]
Aggregate annual servicing fees receivable for phase-in recovery bonds												$ 445,000
Ohio Funding Companies \| Phase In Recovery Bonds
Debt Instrument [Line Items]
Face amount of loan																					$ 445,000,000
AGC
Debt Instrument [Line Items]
FERC-defined equity to total capitalization ratio												45.00%