Commitments and Contingencies - Narrative (Details) $ in Millions	1 Months Ended	6 Months Ended
Nov. 30, 2020 USD ($)	Jun. 30, 2025 USD ($) mGPSite
Commitments And Contingencies Additional Narrative Information [Line Items]
Income Taxes Receivable, Noncurrent		$ 100
Commonwealth Edison Co
Commitments And Contingencies Additional Narrative Information [Line Items]
Mgp Site Contingency Monitoring Count \| mGPSite		16
Deferred Prosecution Agreement Payments	$ 200
PECO Energy Co
Commitments And Contingencies Additional Narrative Information [Line Items]
Mgp Site Contingency Monitoring Count \| mGPSite		6
Baltimore Gas and Electric Company
Commitments And Contingencies Additional Narrative Information [Line Items]
Mgp Site Contingency Monitoring Count \| mGPSite		4
Income Taxes Receivable, Noncurrent		$ 65
Delmarva Power and Light Company
Commitments And Contingencies Additional Narrative Information [Line Items]
Mgp Site Contingency Monitoring Count \| mGPSite		1
Income Taxes Receivable, Noncurrent		$ 10
Potomac Electric Power Company
Commitments And Contingencies Additional Narrative Information [Line Items]
Environmental Liability - Anacostia		47
Environmental Liability - Buzzard Point		10
Income Taxes Receivable, Noncurrent		25
Payments for Environmental Liabilities		12
Exelon Business Services Co Affiliate
Commitments And Contingencies Additional Narrative Information [Line Items]
Insurers' Settlement Payment		40
Settling Shareholders' Attorney Fees		10
Pepco Holdings LLC
Commitments And Contingencies Additional Narrative Information [Line Items]
Income Taxes Receivable, Noncurrent		$ 35

Commitments And Contingencies Additional Narrative Information [Line Items]

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- Definition

Environmental Liability - Anacostia

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- Definition

Environmental Liability - Buzzard Point

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- Definition

Insurers' Settlement Payment

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Number Of Former Manufactured Gas Plant Sites

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Settling Shareholders' Attorney Fees

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- Definition

Carrying amount due after one year of the balance sheet date (or one operating cycle, if longer) from tax authorities as of the balance sheet date representing refunds of overpayments or recoveries based on agreed-upon resolutions of disputes.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(17))
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Amount awarded to other party in judgment or settlement of litigation.

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- Definition

Cash outflows made during the period for environmental remediation activities.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 17
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-17

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