Commitments And Contingencies Additional Narrative Information [Line Items]

No definition available.

Name:	exc_CommitmentsAndContingenciesAdditionalNarrativeInformationLineItems
Namespace Prefix:	exc_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Environmental Liability - Anacostia

+ References

No definition available.

+ Details

Name:	exc_EnvironmentalLiabilityAnacostia
Namespace Prefix:	exc_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Environmental Liability - Buzzard Point

+ References

No definition available.

+ Details

Name:	exc_EnvironmentalLiabilityBuzzardPoint
Namespace Prefix:	exc_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Insurers' Settlement Payment

+ References

No definition available.

+ Details

Name:	exc_InsurersSettlementPayment
Namespace Prefix:	exc_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Number Of Former Manufactured Gas Plant Sites

+ References

No definition available.

+ Details

Name:	exc_NumberOfFormerManufacturedGasPlantSites
Namespace Prefix:	exc_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Settling Shareholders' Attorney Fees

+ References

No definition available.

+ Details

Name:	exc_SettlingShareholdersAttorneyFees
Namespace Prefix:	exc_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Increase (decrease) in the accrual for environmental loss contingencies during the reporting period.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 450
-SubTopic 20
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 5.Y.Q1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480102/450-20-S99-1

+ Details

Name:	us-gaap_AccrualForEnvironmentalLossContingenciesPeriodIncreaseDecrease
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	duration

- 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))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S50
-Paragraph 7
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480657/210-10-S50-7

+ Details

Name:	us-gaap_IncomeTaxesReceivableNoncurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount awarded to other party in judgment or settlement of litigation.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 450
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483076/450-20-50-1

+ Details

Name:	us-gaap_LitigationSettlementAmountAwardedToOtherParty
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- 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

+ Details

Name:	us-gaap_PaymentsForEnvironmentalLiabilities
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

Name:	dei_LegalEntityAxis=exc_CommonwealthEdisonCoMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_EnvironmentalRemediationSiteAxis=exc_AccrualForMgpInvestigationAndRemediationMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	dei_LegalEntityAxis=exc_PECOEnergyCoMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	dei_LegalEntityAxis=exc_BaltimoreGasAndElectricCompanyMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	dei_LegalEntityAxis=exc_DelmarvaPowerandLightCompanyMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	dei_LegalEntityAxis=exc_PotomacElectricPowerCompanyMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	dei_LegalEntityAxis=exc_ExelonBusinessServicesCoAffiliateMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	dei_LegalEntityAxis=exc_PepcoHoldingsLLCMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Commitments and Contingencies - Narrative (Details) $ in Millions			1 Months Ended	9 Months Ended
	Apr. 07, 2026 USD ($)	Apr. 09, 2025 USD ($)	Nov. 30, 2020 USD ($)	Sep. 30, 2026 USD ($) mGPSite	Apr. 11, 2024 USD ($)	Feb. 02, 2024 USD ($)
Commitments And Contingencies Additional Narrative Information [Line Items]
Income Taxes Receivable, Noncurrent				$ 165
Commonwealth Edison Co
Commitments And Contingencies Additional Narrative Information [Line Items]
Mgp Site Contingency Monitoring Count \| mGPSite				16
Deferred Prosecution Agreement Payments			$ 200
Commonwealth Edison Co \| Accrual For MGP Investigation And Remediation
Commitments And Contingencies Additional Narrative Information [Line Items]
Accrual for Environmental Loss Contingencies, Period Increase (Decrease)				$ 12
PECO Energy Co
Commitments And Contingencies Additional Narrative Information [Line Items]
Mgp Site Contingency Monitoring Count \| mGPSite				5
PECO Energy Co \| Accrual For MGP Investigation And Remediation
Commitments And Contingencies Additional Narrative Information [Line Items]
Accrual for Environmental Loss Contingencies, Period Increase (Decrease)				$ 2
Baltimore Gas and Electric Company
Commitments And Contingencies Additional Narrative Information [Line Items]
Mgp Site Contingency Monitoring Count \| mGPSite				4
Income Taxes Receivable, Noncurrent				$ 110
Delmarva Power and Light Company
Commitments And Contingencies Additional Narrative Information [Line Items]
Mgp Site Contingency Monitoring Count \| mGPSite				1
Income Taxes Receivable, Noncurrent				$ 20
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				35
Payments for Environmental Liabilities	$ 12	$ 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				$ 55