Commitments and Contingencies [Line Items]

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- Definition

Number of individual manufactured gas plant sites where monitoring or remediation activities are occurring.

+ References

No definition available.

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- Definition

OtherNonFinancialCommitment1

+ References

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- Definition

Purchase Commitment

+ References

No definition available.

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- Definition

Undiscounted amount of the accrual for environmental loss contingencies.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
-SubTopic 30
-Section 50
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=6393242&loc=d3e13207-110859

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 5.Y.Q1)
-URI http://asc.fasb.org/extlink&oid=27011672&loc=d3e149879-122751

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- Definition

Ratio of Common Equity Tier 1 risk-based capital to risk-weighted assets as defined by regulatory framework.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 505
-Section 50
-Paragraph 1
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=117337116&loc=SL5958568-112826

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- Definition

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

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- Definition

Minimum amount of other commitment not otherwise specified in the taxonomy. Excludes commitments explicitly modeled in the taxonomy, including but not limited to, long-term and short-term purchase commitments, recorded and unrecorded purchase obligations, supply commitments, registration payment arrangements, leases, debt, product warranties, guarantees, environmental remediation obligations, and pensions.

+ References

No definition available.

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Commitments and Contingencies - Narrative (Details) $ in Millions		12 Months Ended
	Mar. 23, 2016 MW	Dec. 31, 2022 MW	Dec. 31, 2021 USD ($) MGPSite	Dec. 31, 2018 MW	Dec. 31, 2017 MW	Dec. 31, 2020 USD ($)
Commitments and Contingencies [Line Items]
Other Commitment			$ 535
Accrual for Environmental Loss Contingencies, Gross			352			$ 366
Deferred Prosecution Payment			200
Commonwealth Edison Co [Member]
Commitments and Contingencies [Line Items]
Other Commitment			$ 224
Sites under study/remediation \| MGPSite			21
Accrual for Environmental Loss Contingencies, Gross			$ 279			293
Deferred Prosecution Payment			200
PECO Energy Co [Member]
Commitments and Contingencies [Line Items]
Other Commitment			$ 181
Sites under study/remediation \| MGPSite			6
Accrual for Environmental Loss Contingencies, Gross			$ 22			23
Baltimore Gas and Electric Company [Member]
Commitments and Contingencies [Line Items]
Other Commitment			$ 5
Sites under study/remediation \| MGPSite			4
Accrual for Environmental Loss Contingencies, Gross			$ 6			2
Banking Regulation, Common Equity Tier One Risk-Based Capital Ratio, Actual			0.48
Pepco Holdings LLC [Member]
Commitments and Contingencies [Line Items]
Other Commitment			$ 54
Accrual for Environmental Loss Contingencies, Gross			42			44
Potomac Electric Power Company [Member]
Commitments and Contingencies [Line Items]
Other Commitment			24
Accrual for Environmental Loss Contingencies, Gross			$ 40			42
Banking Regulation, Common Equity Tier One Risk-Based Capital Ratio, Actual			0.48
Delmarva Power & Light Company [Member]
Commitments and Contingencies [Line Items]
Other Commitment			$ 18
Sites under study/remediation \| MGPSite			1
Accrual for Environmental Loss Contingencies, Gross			$ 1			1
Banking Regulation, Common Equity Tier One Risk-Based Capital Ratio, Actual			0.48
Atlantic City Electric Company [Member]
Commitments and Contingencies [Line Items]
Other Commitment			$ 12
Accrual for Environmental Loss Contingencies, Gross			$ 1			$ 1
Banking Regulation, Common Equity Tier One Risk-Based Capital Ratio, Actual			0.48
Atlantic City Electric Company [Member] \| Minimum [Member]
Commitments and Contingencies [Line Items]
Banking Regulation, Common Equity Tier One Risk-Based Capital Ratio, Actual			0.30
PEPCO Holdings Inc [Member]
Commitments and Contingencies [Line Items]
Other Commitment			$ 513
PEPCO Holdings Inc [Member] \| Pepco Holdings LLC [Member]
Commitments and Contingencies [Line Items]
Other Commitment			320
PEPCO Holdings Inc [Member] \| Potomac Electric Power Company [Member]
Commitments and Contingencies [Line Items]
Other Commitment			120
PEPCO Holdings Inc [Member] \| Delmarva Power & Light Company [Member]
Commitments and Contingencies [Line Items]
Other Commitment			89
PEPCO Holdings Inc [Member] \| Atlantic City Electric Company [Member]
Commitments and Contingencies [Line Items]
Other Commitment			$ 111
PEPCO Holdings Inc [Member] \| Wind Assets [Member]
Commitments and Contingencies [Line Items]
OtherNonFinancialCommitment1 \| MW	100
PEPCO Holdings Inc [Member] \| Wind Assets [Member] \| Delmarva Power & Light Company [Member]
Commitments and Contingencies [Line Items]
Purchase Commitment \| MW	120			40	40
PEPCO Holdings Inc [Member] \| Wind Assets [Member] \| Delmarva Power & Light Company [Member] \| Subsequent Event [Member]
Commitments and Contingencies [Line Items]
Purchase Commitment \| MW		40