Commitments and Contingencies [Line Items]

No definition available.

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- Definition

Total annual retrospective premium obligation under insurance from an industry mutual insurance company.

+ References

No definition available.

+ Details

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- Definition

Distribution by a nuclear industry mutual insurance company to its members. This distribution represents excess funds as a result of positive operating experience.

+ References

No definition available.

+ Details

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- Definition

This represents the maximum total recovery for all losses by all insureds of an industry mutual insurance company in the event of multiple losses by multiple insureds within a twelve-month period.

+ References

No definition available.

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- Definition

This represents the maximum annual retrospective premium obligation that can be assessed to each member by an industry mutual insurance company in the event of a major accidental outage at a power plant incurred by any individual members.

+ References

No definition available.

+ Details

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- Definition

Annual coverage limit provided by the nuclear insurance arrangement for nuclear incident claims.

+ References

No definition available.

+ Details

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- Definition

Maximum annual payment of the assessment per nuclear reactor for a nuclear incident, under the financial protection pool mandated by the Price-Anderson Act. This payment is made by each United States nuclear reactor operator over multiple years in the event of an incident at any United States nuclear reactor, until the total assessment has been fully paid.

+ References

No definition available.

+ Details

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- Definition

Total funds available for nuclear insurance liability claims in a financial protection pool mandated by the Price-Anderson Act.

+ References

No definition available.

+ Details

Name:	ceg_NuclearInsuranceFinancialProtectionPoolValue
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- Definition

Total of allowed cash reimbursements for received for costs incurred from the Department of Energy under the settlement agreement for spent nuclear fuel storage costs that have been incurred due to the delay in the Department of Energy accepting spent nuclear fuel.

+ References

No definition available.

+ Details

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- Definition

Total of allowed cash reimbursements received for cost incurred from the Department of Energy under the settlement agreement for spent nuclear fuel storage costs that have been incurred due to the delay in the Department of Energy accepting spent nuclear fuel after considering amounts due to co-owners.

+ References

No definition available.

+ Details

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- Definition

Interest rate used to calculated interest accrued on one-time fee applicable to nuclear generation through April 6, 1983 under the standard contracts with the Department of Energy which was elected to be deferred with interest until just prior to the first delivery of spent nuclear fuel to the Department of Energy. The interest rate used is the 13-week Treasury Rate.

+ References

No definition available.

+ Details

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- Definition

Recorded amount of the accrual for a material component of an environmental loss contingency.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 5.Y.Q2)
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- Definition

Undiscounted amount of the accrual for environmental loss contingencies.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
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- Definition

Amount of gain (loss) recognized in settlement of litigation and insurance claims. Excludes claims within an insurance entity's normal claims settlement process.

+ References

+ Details

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- Definition

Carrying amount as of the balance sheet date of reserves for the costs of settling insured claims and costs incurred in the claims settlement process attributable to asbestos and environmental claims, before estimated recoveries from reinsurers.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-Paragraph 3
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- Definition

Carrying amount of reserve for known or estimated probable loss from litigation, which may include attorneys' fees and other litigation costs, which is expected to be paid within one year of the date of the statement of financial position.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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- Definition

The value (monetary amount) of the award the plaintiff seeks in the legal matter.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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-Name Accounting Standards Codification
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- Definition

Number of pending claims pertaining to a loss contingency.

+ References

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Commitments and Contingencies - Narrative (Details) $ in Millions		12 Months Ended
	Mar. 22, 2021 USD ($)	Dec. 31, 2022 USD ($) Open_claim	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2016 USD ($)	Jun. 30, 2022 USD ($)	Aug. 03, 2020 USD ($)	Mar. 31, 2019 USD ($)	Sep. 30, 2018 USD ($)	Jan. 01, 2017 USD ($)
Commitments and Contingencies [Line Items]
Gain (loss) recognized		$ 50	$ 0	$ 0
Nuclear financial protection pool value										$ 450
Maximum recovery limit from a nuclear industry mutual insurance company in the event of multiple losses										13,200
Maximum annual assessment payment mandated by Price-Anderson Act for a nuclear incident										2,800
Maximum aggregate annual retrospective premium obligation		252
Maximum recovery, aggregate		3,200
Total cumulative cash reimbursements		1,731
Net cumulative cash reimbursements		1,501
Accrued undiscounted amounts, environmental liabilities		119	120
Asbestos-related bodily injury claims		$ 95	81
Former ComEd units
Commitments and Contingencies [Line Items]
Treasury interest rate		4.169%
Fitzpatrick
Commitments and Contingencies [Line Items]
Treasury interest rate		3.415%
Prior Merger Commitment
Commitments and Contingencies [Line Items]
Gain (loss) recognized		$ 50
Prior Merger Commitment
Commitments and Contingencies [Line Items]
Gain (loss) recognized					$ (50)
LDC Damages
Commitments and Contingencies [Line Items]
Avoided damages	$ 40
Damages sought			40			$ 11
West Lake
Commitments and Contingencies [Line Items]
Accrued undiscounted amounts, environmental liabilities								$ 295	$ 50
Environmental loss contingencies							$ 90
Open Claims
Commitments and Contingencies [Line Items]
Asbestos-related bodily injury claims		$ 23
Open claims \| Open_claim		253
Estimated Future Claims
Commitments and Contingencies [Line Items]
Asbestos-related bodily injury claims		$ 72
Nuclear Insurance Premiums
Commitments and Contingencies [Line Items]
Nuclear insurance liability limit per incident		13,700
Nuclear Insurance Premiums \| Maximum
Commitments and Contingencies [Line Items]
Nuclear financial protection pool value										$ 413
Guarantees Other Than Letters Of Credit and Nuclear Insurance Premiums
Commitments and Contingencies [Line Items]
Annual distribution, portion		$ 30	$ 114	$ 75