Cash Proceeds from Direct Finance Lease Contract Termination

No definition available.

Name:	exc_ProceedsFromLeaseTermination
Namespace Prefix:	exc_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount classified as assets attributable to disposal group held for sale or disposed of, expected to be disposed of within one year or the normal operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 45
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=65878427&loc=d3e1107-107759

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-Publisher FASB
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-Section 50
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-Section 45
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+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- References

No definition available.

+ Details

Name:	us-gaap_CapitalLeasesNetInvestmentInDirectFinancingLeasesAbstract
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- Definition

The estimate of the lease property's economic value at the end of the direct financing lease term excluding any amounts guaranteed by either the lessee or a third-party.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 30
-Section 50
-Paragraph 4
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=25496975&loc=d3e45377-112738

+ Details

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

- Definition

Gain (loss) related to the termination of a contract between the parties. The termination may be due to many causes including early termination of a lease by a lessee, a breach of contract by one party, or a failure to perform.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
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+ Details

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Balance Type:	credit
Period Type:	duration

- Definition

The charge against earnings resulting from the aggregate write down of tangible assets from their carrying value to their fair value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
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+ Details

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Period Type:	duration

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- Details

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Impairment of Long-Lived Assets (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Mar. 31, 2016
Capital Leases, Net Investment in Direct Financing Leases [Abstract]
Estimated residual value of leased assets	$ 356
Proceeds From Lease Termination	360	$ 0
Gain (Loss) on Contract Termination	4
Wind Assets [Member]
Capital Leases, Net Investment in Direct Financing Leases [Abstract]
Tangible Asset Impairment Charges	36
Disposal Group, Including Discontinued Operation, Assets, Current	24		$ 60
Constellation Energy Group LLC [Member]
Capital Leases, Net Investment in Direct Financing Leases [Abstract]
Tangible Asset Impairment Charges	119
Disposal Group, Including Discontinued Operation, Assets, Current	$ 61