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Minimum Expectation Of Tax Position To Be Realized

No definition available.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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The capitalized costs incurred during the period (excluded from amortization) to obtain access to proved reserves and to provide facilities for extracting, treating, gathering and storing the oil and gas.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 932
-SubTopic 10
-Section S99
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-Subparagraph (SX 210.4-10(c)(7)(ii))
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-Subparagraph (SX 210.4-10(c)(3)(ii)(A))
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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
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Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which is directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent (that is, noncontrolling interest, previously referred to as minority interest).

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
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-Subparagraph (SX 210.9-03(22))
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-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(24))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.31)
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Amount of the effect of a change in accounting principle on net income.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
-Section 50
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Percentage of subsidiary's or equity method investee's stock owned by parent immediately after all stock transactions.

No definition available.

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Amount of operating expense for routine plant maintenance, repairs and operations of regulated operation.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
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Amount of other operating expense of regulated operation.

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Name:	exc_SubsidiaryCompaniesAxis=exc_CommonwealthEdisonCompanyMember
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Name:	exc_SubsidiaryCompaniesAxis=exc_CengMember
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Name:	dei_LegalEntityAxis=exc_ExelonGenerationCoLLCMember
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Name:	dei_LegalEntityAxis=exc_PotomacElectricPowerCompanyMember
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Data Type:	na
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Name:	dei_LegalEntityAxis=exc_DelmarvaPowerandLightCompanyMember
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Data Type:	na
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Name:	dei_LegalEntityAxis=exc_PepcoHoldingsLLCMember
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Name:	us-gaap_RangeAxis=us-gaap_MinimumMember
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