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The penalty assessed under a consent decree.

No definition available.

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Number of individual manufactured gas plant sites at which the respective state environmental agency has approved a cleanup plan.

No definition available.

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Total number of individual manufactured gas plant sites with associated possible environmental loss contingencies related to remediation.

No definition available.

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

No definition available.

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QuantityOfMineralOilSPill

No definition available.

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Recorded amount of the accrual for a material component of an environmental loss contingency.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section S99
-Paragraph 1
-Subparagraph (SAB TOPIC 5.Y.Q2)
-URI http://asc.fasb.org/extlink&oid=27011672&loc=d3e149879-122751

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Total anticipated costs associated with remediation, site restoration, postclosure, monitoring commitments, or other exit costs that may occur on the sale, disposal, or abandonment of a particular property resulting from unanticipated contamination of the assets.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
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-Section S99
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The charge against earnings in the period for known or estimated future costs arising from requirements to perform environmental remediation activities.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
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-Section 50
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Reflects the estimated amount of loss from the specified contingency as of the balance sheet date.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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The total number of new claims filed pertaining to a loss contingency during the period.

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The number of real estate properties owned as of the balance sheet date.

No definition available.

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The amount of cash paid for the settlement of litigation or for other legal issues during the period.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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Best estimate of the loss exposure for reasonably possible environmental contingencies at an individual site for which no accrual has been recorded.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
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-Section 50
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Name:	dei_LegalEntityAxis=exc_PecoEnergyCoMember
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