Commitments And Contingent Liabilities (Nuclear Insurance Coverages and Assessments) (Details) $ in Millions		1 Months Ended	12 Months Ended
		Jan. 31, 2017 USD ($)	Dec. 31, 2016 USD ($) MW
Other Commitments [Line Items]
Retrospective Assessment Power Generation | MW			100
Inflation Adjustment For Assessment Years			5 years
Nuclear Insurance Aggregate Limit			$ 3,200.0
Ownership Interest Per Reactor Per Incident			127.0
Ownership Interest Payable Per Reactor Per Incident Per Year			19.0
Maximum Aggregate Assessment Per Incident			401.0
Maximum Aggregate Annual Assessment			60.0
Property limit in excess			1,500.0
Total Site Coverage [Member]
Other Commitments [Line Items]
Nuclear Liability, Total	[1]		13,361.0
Replacement Power Total
Retrospective Assessments [Member]
Other Commitments [Line Items]
Nuclear Liability, Total	[1]		401.0
Replacement Power Total			78.0
Power With Exelon Generation [Member]
Other Commitments [Line Items]
Blanket limit shared			300.0
ANI [Member] | Total Site Coverage [Member]
Other Commitments [Line Items]
Public and Nuclear Worker Liability, Primary Layer	[2]		375.0
ANI [Member] | Retrospective Assessments [Member]
Other Commitments [Line Items]
Public and Nuclear Worker Liability, Primary Layer	[2]		0.0
Price-Anderson Act [Member] | Total Site Coverage [Member]
Other Commitments [Line Items]
Nuclear Liability, Excess Layer	[3]		12,986.0
Price-Anderson Act [Member] | Retrospective Assessments [Member]
Other Commitments [Line Items]
Nuclear Liability, Excess Layer	[3]		401.0
NEIL II (Salem/Hope Creek/Peach Bottom) [Member] | Total Site Coverage [Member]
Other Commitments [Line Items]
Property Damage, Primary Layer			1,500.0
Property Damage, Excess Layers	[4]		300.0
NEIL II (Salem/Hope Creek/Peach Bottom) [Member] | Retrospective Assessments [Member]
Other Commitments [Line Items]
Property Damage, Primary Layer			35.0
NEIL II (Salem/Hope Creek/Peach Bottom) [Member] | Retrospective Assessments Nuclear [Member]
Other Commitments [Line Items]
Property Damage, Excess Layers	[4]		2.0
NEIL II (Salem/Hope Creek/Peach Bottom) [Member] | Retrospective Assessments, Non-Nuclear [Member]
Other Commitments [Line Items]
Property Damage, Excess Layers	[4]		1.0
NEIL II (Salem/Hope Creek/Peach Bottom) [Member] | Total Site Coverage for Non Nuclear Event [Member]
Other Commitments [Line Items]
Property Damage, Excess Layers	[4]		300.0
NEIL I (Peach Bottom) [Member] | Total Site Coverage [Member]
Other Commitments [Line Items]
Property Damage, Primary Layer			1,500.0
Property Damage, Excess Layers	[4]		300.0
Accidental Outage	[5]		245.0
Indemnity limit on weekly indemnity			$ 2.3
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] | Retrospective Assessments [Member]
Other Commitments [Line Items]
Property Damage, Primary Layer			$ 14.0
Accidental Outage	[5]		8.0
NEIL I (Peach Bottom) [Member] | Retrospective Assessments Nuclear [Member]
Other Commitments [Line Items]
Property Damage, Excess Layers	[4]		1.0
NEIL I (Peach Bottom) [Member] | Retrospective Assessments, Non-Nuclear [Member]
Other Commitments [Line Items]
Property Damage, Excess Layers	[4]		1.0
NEIL I (Peach Bottom) [Member] | Total Site Coverage for Non Nuclear Event [Member]
Other Commitments [Line Items]
Property Damage, Excess Layers	[4]		600.0
Accidental Outage	[5]		164.0
Indemnity limit on weekly indemnity			$ 2.3
Weekly indemnity, time period			364 days
Indemnity period, after initial period, percentage			80.00%
Indemnity period, after initial period, time period			168 days
NEIL 1 (Salem) [Member] | Total Site Coverage [Member]
Other Commitments [Line Items]
Accidental Outage	[5]		$ 281.0
Indemnity limit on weekly indemnity			$ 2.5
Weekly indemnity, time period			364 days
Indemnity period, after initial period, percentage			80.00%
Indemnity period, after initial period, time period			532 days
NEIL 1 (Salem) [Member] | Retrospective Assessments [Member]
Other Commitments [Line Items]
Accidental Outage	[5]		$ 9.0
NEIL 1 (Salem) [Member] | Total Site Coverage for Non Nuclear Event [Member]
Other Commitments [Line Items]
Accidental Outage	[5]		188.0
Indemnity limit on weekly indemnity			$ 2.5
Weekly indemnity, time period			364 days
Indemnity period, after initial period, percentage			80.00%
Indemnity period, after initial period, time period			203 days
NEIL I (Hope Creek) [Member] | Total Site Coverage [Member]
Other Commitments [Line Items]
Accidental Outage	[5]		$ 490.0
Indemnity limit on weekly indemnity			$ 4.5
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] | Retrospective Assessments [Member]
Other Commitments [Line Items]
Accidental Outage	[5]		$ 7.0
NEIL I (Hope Creek) [Member] | Total Site Coverage for Non Nuclear Event [Member]
Other Commitments [Line Items]
Accidental Outage	[5]		328.0
Indemnity limit on weekly indemnity			$ 4.5
Weekly indemnity, time period			364 days
Indemnity period, after initial period, percentage			80.00%
Indemnity period, after initial period, time period			182 days
Subsequent Event [Member] | ANI [Member] | Total Site Coverage [Member]
Other Commitments [Line Items]
Public and Nuclear Worker Liability, Primary Layer	[2]	$ 450.0

[1] Maximum limit of liability under the Price-Anderson Act for each nuclear incident per site.

[2] The primary limit for Public Liability is a per site aggregate limit with no potential for retrospective assessment. The Nuclear Worker Liability represents the potential liability from third-party workers claiming exposure to the nuclear energy hazard. 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 September 10, 2013. The next adjustment is due on or before September 10, 2018. This retrospective program is in excess of the Public and Nuclear Worker Liability primary layers.

[4] For nuclear event property limits in excess of $1.5 billion, Power purchases a $300 million Excess Policy for the Salem/Hope Creek site, and a $300 million Excess Policy only for Power’s 50% interest in Peach Bottom. This limit is not subject to reinstatement in the event of a loss. In addition, for non-nuclear event limits in excess of $1.5 billion, Power maintains a $300 million limit for the combined Salem/Hope Creek sites. Exelon maintains a $600 million non-nuclear event limit for Peach Bottom.

[5] Peach Bottom 2 and 3 have an aggregate nuclear indemnity limit based on a weekly indemnity of $2.3 million for 52 weeks followed by 80% of the weekly indemnity for 68 weeks. Peach Bottom 2 and 3 have an aggregate non-nuclear indemnity limit based on a weekly indemnity of $2.3 million for 52 weeks followed by 80% of the weekly indemnity for 24 weeks. Salem 1 and 2 have an aggregate nuclear indemnity limit based on a weekly indemnity of $2.5 million for 52 weeks followed by 80% of the weekly indemnity for 76 weeks. Salem 1 and 2 have an aggregate non-nuclear indemnity limit based on a weekly indemnity of $2.5 million for 52 weeks followed by 80% of the weekly indemnity for 29 weeks. Hope Creek has an aggregate nuclear indemnity limit based on a weekly indemnity of $4.5 million for 52 weeks followed by 80% of the weekly indemnity for 71 weeks. Hope Creek has an aggregate non-nuclear indemnity limit based on a weekly indemnity of $4.5 million for 52 weeks followed by 80% of the weekly indemnity for 26 weeks.