Early Plant Retirements - Pretax Expense (Details) - Facility Closing [Member] - Byron Dresden $ in Millions	3 Months Ended
Mar. 31, 2021 USD ($)
Accelerated depreciation	$ 620
Accelerated nuclear fuel amortization	54
Operating and maintenance	2
Asset Retirement Obligation Contractual Offset	(226)
Restructuring and Related Cost, Incurred Cost	450
Exelon Generation Co L L C [Member]
Accelerated depreciation	620
Accelerated nuclear fuel amortization	54
Operating and maintenance	2
Asset Retirement Obligation Contractual Offset	(226)
Restructuring and Related Cost, Incurred Cost	$ 450

Asset Retirement Obligation Contractual Offset

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- Definition

The amount of capitalized nuclear fuel costs that are charged to fuel expense during the period using the unit-of-production method.

+ References

No definition available.

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- Definition

The total amount of other operating cost and expense items that are associated with the entity's normal revenue producing operation.

+ References

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- Definition

Discloses the amount charged against the accrued restructuring reserves, or earnings if not previously accrued, during the period for the specified type of restructuring cost.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

Amount of accelerated depreciation charged against earnings associated with exit from or disposal of business activities or restructuring plan.

+ References

No definition available.

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