CENG Preferred Distribution Return

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- Definition

Capacity of facility of company owned solar distribution generation facilities.

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Amount of increase (decrease) in the asset retirement obligation from changes in the amount or timing of the estimated cash flows associated with the settlement of the obligation.

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Amount of gain (loss) from deconsolidation of subsidiary and derecognition of group of assets constituting transfer of business or nonprofit activity, excluding conveyance of oil and gas mineral rights and transfer of good or service in contract with customer.

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Amount of consideration received or receivable for the disposal of assets and liabilities, including discontinued operation.

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No definition available.

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For an unclassified balance sheet, amount of receivables due from an entity that is affiliated with the reporting entity by means of direct or indirect ownership.

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

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Cash outflow to owners or shareholders, excluding ordinary dividends. Includes special dividends.

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The cash inflow associated with the amount received from the sale of a portion of the company's business, for example a segment, division, branch or other business, during the period.

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Mergers, Acquisitions, and Dispositions - Narrative (Details) $ in Millions			12 Months Ended
	Feb. 28, 2018 USD ($)	Apr. 01, 2014 USD ($)	Dec. 31, 2020 USD ($) MW	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Dec. 08, 2020 USD ($)
Business Dispositions
Asset Retirement Obligation, Revision of Estimate					$ 20
Minimum [Member]
Business Acquisitions
Equity Method Investment, Ownership Percentage			20.00%
Maximum [Member]
Business Acquisitions
Equity Method Investment, Ownership Percentage			50.00%
Operating Expense [Member]
Business Dispositions
Asset Retirement Obligation, Revision of Estimate			$ 60	$ (150)
Solar Business [Member]
Business Dispositions
Capacity Of Facility Of Company Owned Solar Distribution Generation Facilities \| MW			360
Disposal Group, Including Discontinued Operation, Consideration						$ 810
Solar Business [Member] \| Minimum [Member]
Business Dispositions
Deconsolidation, Gain (Loss), Amount			$ 75
Solar Business [Member] \| Maximum [Member]
Business Dispositions
Deconsolidation, Gain (Loss), Amount			$ 125
Oyster Creek [Member] \| Operating Expense [Member]
Business Dispositions
Asset Retirement Obligation, Revision of Estimate				9	84
Electrical Contracting Business [Member]
Business Dispositions
Proceeds from Divestiture of Businesses	$ 87
CENG [Member]
Business Acquisitions
Equity Method Investment, Ownership Percentage			50.01%
Payments of Capital Distribution		$ 400
Due from Affiliates		400	$ 619
CENG Preferred Distribution Return			8.50%
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners			49.99%
Exelon Generation Co L L C [Member]
Business Dispositions
Asset Retirement Obligation, Revision of Estimate					0
Exelon Generation Co L L C [Member] \| Operating Expense [Member]
Business Dispositions
Asset Retirement Obligation, Revision of Estimate			$ 60	(150)
Exelon Generation Co L L C [Member] \| Solar Business [Member]
Business Dispositions
Capacity Of Facility Of Company Owned Solar Distribution Generation Facilities \| MW			360
Disposal Group, Including Discontinued Operation, Consideration						$ 810
Exelon Generation Co L L C [Member] \| Solar Business [Member] \| Minimum [Member]
Business Dispositions
Deconsolidation, Gain (Loss), Amount			$ 75
Exelon Generation Co L L C [Member] \| Solar Business [Member] \| Maximum [Member]
Business Dispositions
Deconsolidation, Gain (Loss), Amount			$ 125
Exelon Generation Co L L C [Member] \| Oyster Creek [Member] \| Operating Expense [Member]
Business Dispositions
Asset Retirement Obligation, Revision of Estimate				$ 9	$ 84
Exelon Generation Co L L C [Member] \| Electrical Contracting Business [Member]
Business Dispositions
Proceeds from Divestiture of Businesses	$ 87
Exelon Generation Co L L C [Member] \| CENG [Member]
Business Acquisitions
Equity Method Investment, Ownership Percentage			50.01%	50.01%
Payments of Capital Distribution		400
Due from Affiliates		$ 400	$ 619
CENG Preferred Distribution Return			8.50%
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners			49.99%
Nine Mile Point [Member] \| CENG [Member]
Business Acquisitions
Equity Method Investment, Ownership Percentage			82.00%
Nine Mile Point [Member] \| Exelon Generation Co L L C [Member] \| CENG [Member]
Business Acquisitions
Equity Method Investment, Ownership Percentage			82.00%