Commitments And Contingent Liabilities (Nuclear Insurance Coverages and Assessments) (Details) (USD $)	12 Months Ended
	Dec. 31, 2012 MW
Nuclear Insurance Aggregate Limit	$ 3,200,000,000
Limit Of Liability Per Price Anderson Act	12,600,000,000
Ownership Interest Per Reactor Per Incident	118,000,000
Ownership Interest Payable Per Reactor Per Incident Per Year	18,000,000
Maximum Aggregate Assessment Per Incident	370,000,000
Maximum Aggregate Annual Assessment	55,000,000
Retrospective assessment, power generation, MW	100
Inflation adjustment for assessment, years	5 years
Property limit in excess	1,250,000,000
Total Site Coverage [Member]
Nuclear Liability, Total	12,594,000,000	[1]
Property Damage, Total	2,100,000,000
Replacement Power, Total	1,016,000,000
Retrospective Assessments [Member]
Nuclear Liability, Total	370,000,000
Property Damage, Total	35,000,000
Replacement Power, Total	19,000,000
Power With Exelon Generation [Member]
Blanket limit shared	850,000,000
ANI [Member] | Total Site Coverage [Member]
Public and Nuclear Worker Liability, Primary Layer	375,000,000	[2]
ANI [Member] | Retrospective Assessments [Member]
Public and Nuclear Worker Liability, Primary Layer	0
Price-Anderson Act [Member] | Total Site Coverage [Member]
Nuclear Liability, Excess Layer	12,219,000,000	[3]
Price-Anderson Act [Member] | Retrospective Assessments [Member]
Nuclear Liability, Excess Layer	370,000,000
NEIL II (Salem/Hope Creek/Peach Bottom) [Member] | Total Site Coverage [Member]
Property Damage, Primary Layer	500,000,000
Property Damage, Excess Layers	750,000,000
NEIL II (Salem/Hope Creek/Peach Bottom) [Member] | Retrospective Assessments [Member]
Property Damage, Primary Layer	22,000,000
Property Damage, Excess Layers	8,000,000
NEIL Blanket Excess (Salem/Hope Creek/Peach Bottom) [Member] | Total Site Coverage [Member]
Property Damage, Excess Layers	850,000,000	[4]
NEIL Blanket Excess (Salem/Hope Creek/Peach Bottom) [Member] | Retrospective Assessments [Member]
Property Damage, Excess Layers	5,000,000
NEIL I (Peach Bottom) [Member]
Indemnity limit on weekly indemnity	2,300,000
Weekly indemnity, time period	364 days
Indemnity period, after initial period, percentage	80.00%
Indemnity period, after initial period, time period	476 days
NEIL I (Peach Bottom) [Member] | Total Site Coverage [Member]
Accidental Outage	245,000,000	[5]
NEIL I (Peach Bottom) [Member] | Retrospective Assessments [Member]
Accidental Outage	6,000,000
NEIL I (Salem) [Member]
Indemnity limit on weekly indemnity	2,500,000
Weekly indemnity, time period	364 days
Indemnity period, after initial period, percentage	80.00%
Indemnity period, after initial period, time period	525 days
NEIL I (Salem) [Member] | Total Site Coverage [Member]
Accidental Outage	281,000,000	[5]
NEIL I (Salem) [Member] | Retrospective Assessments [Member]
Accidental Outage	7,000,000
NEIL I (Hope Creek) [Member]
Indemnity limit on weekly indemnity	4,500,000
Weekly indemnity, time period	364 days
Indemnity period, after initial period, percentage	80.00%
Indemnity period, after initial period, time period	497 days
NEIL I (Hope Creek) [Member] | Total Site Coverage [Member]
Accidental Outage	490,000,000	[5]
NEIL I (Hope Creek) [Member] | Retrospective Assessments [Member]
Accidental Outage	$ 6,000,000

[1] Limit of liability under the Price-Anderson Act for each nuclear incident.

[2] The primary limit for Public Liability is a per site aggregate limit with no potential for assessment. The Nuclear Worker Liability represents the potential liability from workers claiming exposure to the hazard of nuclear radiation. This coverage is subject to an industry aggregate limit that is subject to reinstatement at ANI discretion.

[3] Retrospective premium program under the Price-Anderson Act liability provisions of the Atomic Energy Act of 1954, as amended. Power is subject to retrospective assessment with respect to loss from an incident at any licensed nuclear reactor in the United States that produces greater than 100 MW of electrical power. This retrospective assessment can be adjusted for inflation every five years. The last adjustment was effective as of October 29, 2008. The next adjustment is due on or before October 29, 2013. This retrospective program is in excess of the Public and Nuclear Worker Liability primary layers.

[4] For property limits in excess of $1.25 billion, Power participates in a Blanket Limit policy where the $850 million limit is shared by Power with Exelon Generation among the Braidwood, Byron, Clinton, Dresden, La Salle, Limerick, Oyster Creek, Quad Cities, TMI-1 facilities owned by Exelon Generation and the Peach Bottom, Salem and Hope Creek facilities. This limit is not subject to reinstatement in the event of a loss. Participation in this program materially reduces Power’s premium and the associated potential assessment.

[5] Peach Bottom has an aggregate indemnity limit based on a weekly indemnity of $2.3 million for 52 weeks followed by 80% of the weekly indemnity for 68 weeks. Salem has an aggregate indemnity limit based on a weekly indemnity of $2.5 million for 52 weeks followed by 80% of the weekly indemnity for 75 weeks. Hope Creek has an aggregate indemnity limit based on a weekly indemnity of $4.5 million for 52 weeks followed by 80% of the weekly indemnity for 71 weeks.