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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- Definition

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
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- Definition

The current carrying amount of the liability for the freestanding or embedded guarantor's obligations under the guarantee or each group of similar guarantees.

+ References

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-Publisher FASB
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- Definition

Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

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- Definition

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

+ References

No definition available.

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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.

+ References

No definition available.

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Variable Interest Entities - Narrative (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019	Apr. 01, 2014
Variable Interest Entity [Line Items]
Guarantee obligations maximum exposure	$ 71
Exelon Generation Co L L C [Member] \| Distributed Energy Company [Member]
Variable Interest Entity [Line Items]
Equity Method Investment, Ownership Percentage		90.00%
Exelon Generation Co L L C [Member] \| VIE Distributed Energy Company [Member]
Variable Interest Entity [Line Items]
Equity Method Investment, Ownership Percentage		90.00%
CENG [Member]
Variable Interest Entity [Line Items]
Equity Method Investment, Ownership Percentage	50.01%
Due from Affiliates	$ 619		$ 400
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners	49.99%
CENG [Member] \| Exelon Generation Co L L C [Member]
Variable Interest Entity [Line Items]
Equity Method Investment, Ownership Percentage	50.01%	50.01%
Due from Affiliates	$ 619		400
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners	49.99%
EGRP [Member] \| Exelon Generation Co L L C [Member]
Variable Interest Entity [Line Items]
Equity Method Investment, Ownership Percentage		51.00%
Antelope Valley [Member] \| Exelon Generation Co L L C [Member]
Variable Interest Entity [Line Items]
Equity Method Investment, Ownership Percentage		100.00%
Distributed Energy Company [Member] \| Exelon Generation Co L L C [Member]
Variable Interest Entity [Line Items]
Equity Method Investment, Ownership Percentage		31.00%
NER [Member] \| Exelon Generation Co L L C [Member]
Variable Interest Entity [Line Items]
Equity Method Investment, Ownership Percentage		100.00%
Variable Interest Entity, Primary Beneficiary [Member] \| CENG [Member] \| Payment Guarantee [Member]
Variable Interest Entity [Line Items]
Guarantee obligations maximum exposure			245
Variable Interest Entity, Primary Beneficiary [Member] \| CENG [Member] \| Financial Guarantee [Member]
Variable Interest Entity [Line Items]
Guarantee obligations maximum exposure			$ 165
Variable Interest Entity, Primary Beneficiary [Member] \| CENG [Member] \| Exelon Generation Co L L C [Member]
Variable Interest Entity [Line Items]
Parental guarantee provided	$ 688
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners		49.99%
Variable Interest Entity, Primary Beneficiary [Member] \| EGRP [Member] \| Exelon Generation Co L L C [Member] \| Wind project entities [Member]
Variable Interest Entity [Line Items]
Equity Method Investment, Ownership Percentage		100.00%
Variable Interest Entity, Primary Beneficiary [Member] \| EGRP [Member] \| Exelon Generation Co L L C [Member] \| Solar project entities [Member]
Variable Interest Entity [Line Items]
Equity Method Investment, Ownership Percentage		100.00%