Name:	exc_EstimatedPercentOfGasPurchasesBeingHedged
Namespace Prefix:	exc_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

The percent for the expected/target percentage of future generation being hedged at an electric generation company in the next twelve months. The percentage of expected generation hedged is calculated as the amount of equivalent sales divided by the expected generation. Expected generation represents the amount of energy estimated to be generated or purchased through owned or contracted capacity. Equivalent sales represent all hedging products, which include cash-flow hedges, other derivatives and certain non-derivative contracts including sales to affiliates to serve their retail load.

No definition available.

Name:	exc_ExpectedGenerationHedgedInNextTwelveMonths
Namespace Prefix:	exc_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

The percent for the expected/target percentage of future generation being hedged at an electric generation company in year three. The percentage of expected generation hedged is calculated as the amount of equivalent sales divided by the expected generation. Expected generation represents the amount of energy estimated to be generated or purchased through owned or contracted capacity. Equivalent sales represent all hedging products, which include cash-flow hedges, other derivatives and certain non-derivative contracts including sales to affiliates to serve their retail load.

No definition available.

Name:	exc_ExpectedGenerationHedgedInYearThree
Namespace Prefix:	exc_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

The percent for the expected/target percentage of future generation being hedged at an electric generation company in year two. The percentage of expected generation hedged is calculated as the amount of equivalent sales divided by the expected generation. Expected generation represents the amount of energy estimated to be generated or purchased through owned or contracted capacity. Equivalent sales represent all hedging products, which include cash-flow hedges, other derivatives and certain non-derivative contracts including sales to affiliates to serve their retail load.

No definition available.

Name:	exc_ExpectedGenerationHedgedInYearTwo
Namespace Prefix:	exc_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

Name:	exc_PercentOfExpectedGenerationBeingHedgedAbstract
Namespace Prefix:	exc_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

Name:	exc_PercentOfGasPurchasesBeingHedgedAbstract
Namespace Prefix:	exc_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

The volume in GWh of energy-related derivative contracts entered into purely to profit from market prices changes as opposed to hedging an exposure.

No definition available.

Name:	exc_ProprietaryTradingVolumes
Namespace Prefix:	exc_
Data Type:	xbrli:decimalItemType
Balance Type:	na
Period Type:	duration

Name:	exc_ProprietaryTradingVolumesAbstract
Namespace Prefix:	exc_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

The remaining swap contract volumes in MW on the financial swap contract entered into between related parties.

No definition available.

Name:	exc_SwapContractVolumes
Namespace Prefix:	exc_
Data Type:	xbrli:decimalItemType
Balance Type:	na
Period Type:	duration