Regulatory Matters - Narrative (Details) $ in Millions	3 Months Ended
Mar. 31, 2022 USD ($)
PECO Energy Co [Member]
Regulatory Matters Additional Narrative Information [Line Items]
Increase (Decrease) in Regulatory Assets	$ 66
Increase (Decrease) in Regulatory Liabilities	(112)
PECO Energy Co [Member] \| Nuclear Decommissioning [Member]
Regulatory Matters Additional Narrative Information [Line Items]
Increase (Decrease) in Regulatory Liabilities	(111)
PECO Energy Co [Member] \| Deferred Income Tax Charge [Member]
Regulatory Matters Additional Narrative Information [Line Items]
Increase (Decrease) in Regulatory Assets	60
Baltimore Gas and Electric Company [Member]
Regulatory Matters Additional Narrative Information [Line Items]
Increase (Decrease) in Regulatory Assets	(50)
Increase (Decrease) in Regulatory Liabilities	(53)
Baltimore Gas and Electric Company [Member] \| Deferred Income Tax Charge [Member]
Regulatory Matters Additional Narrative Information [Line Items]
Increase (Decrease) in Regulatory Liabilities	(65)
Baltimore Gas and Electric Company [Member] \| Electric Energy and Natural Gas Cost [Member]
Regulatory Matters Additional Narrative Information [Line Items]
Increase (Decrease) in Regulatory Assets	(19)
Baltimore Gas and Electric Company [Member] \| Energy Efficiency and Demand Response Programs
Regulatory Matters Additional Narrative Information [Line Items]
Increase (Decrease) in Regulatory Assets	(16)
Atlantic City Electric Company [Member]
Regulatory Matters Additional Narrative Information [Line Items]
Contract Termination Liability	203
Increase (Decrease) in Regulatory Assets	205
Increase (Decrease) in Regulatory Liabilities	(19)
Atlantic City Electric Company [Member] \| Other Current Liabilities
Regulatory Matters Additional Narrative Information [Line Items]
Contract Termination Liability	85
Atlantic City Electric Company [Member] \| Other Noncurrent Liabilities
Regulatory Matters Additional Narrative Information [Line Items]
Contract Termination Liability	118
Atlantic City Electric Company [Member] \| Deferred Income Tax Charge [Member]
Regulatory Matters Additional Narrative Information [Line Items]
Increase (Decrease) in Regulatory Liabilities	(9)
Atlantic City Electric Company [Member] \| Electric Transmission Formula Rate Annual Reconciliations [Member]
Regulatory Matters Additional Narrative Information [Line Items]
Increase (Decrease) in Regulatory Liabilities	$ (5)

Contract Termination Liability

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- Definition

Regulatory Matters Additional Narrative Information [Line Items]

+ References

No definition available.

+ Details

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- Definition

The increase (decrease) during the reporting period in the value of other assets that are created when regulatory agencies permits public utilities to defer costs to the balance sheet.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3602-108585

+ Details

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- Definition

The increase (decrease) during the reporting period in regulated liabilities. Regulated liabilities are created when regulatory agency permits an entity to defer revenues to the balance sheet.

+ References

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