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Retirement Benefits - Narrative (Details) $ in Millions | 9 Months Ended
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Sep. 30, 2024 USD ($)
Defined Benefit Plan Disclosure [Line Items] |
Increase (Decrease) in Obligation, Pension Benefits | $ 98
Increase (Decrease) in Obligation, Other Postretirement Benefits | 1
Accumulated Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss), after Tax | 25
Defined Benefit Plan Amounts Recognized In Regulatory Assets Before Tax | 66
Defined Benefit Plan Amounts Recognized In Regulatory Liabilities Before Tax | $ 2
Pension Plan, Defined Benefit [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Expected return on assets | 7.00%
Discount rate | 5.19%
Other Postretirement Benefit Plan, Defined Benefit [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Expected return on assets | 6.50%
Discount rate | 5.17%

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- Definition The aggregate net gain or loss and net prior service cost or credit recognized in regulatory assets, including amounts arising during the period and reclassification adjustments of regulatory assets as a result of being recognized as components of net periodic benefit cost for the period. + References No definition available. + Details
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- Definition Increase in regulatory liabilities due to updated valuation received by Exelon for its legacy pension and other postretirement benefit obligations. + References No definition available. + Details
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- Definition Amount, after tax, of accumulated other comprehensive income (loss) for gain (loss) of defined benefit plan, that has not been recognized in net periodic benefit (cost) credit. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14A -Publisher FASB -URI https://asc.fasb.org/1943274/2147482790/220-10-45-14A Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (j) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 + Details
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- Definition Weighted average rate for present value of future retirement benefits cash flows, used to determine net periodic benefit cost of defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (k)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 + Details
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- Definition Weighted average rate of return on plan assets, reflecting average rate of earnings expected on existing plan assets and expected contributions, used to determine net periodic benefit cost of defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 8 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-8 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (k)(3) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 + Details
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- Definition Amount of increase (decrease) in obligation for pension benefits. Includes, but is not limited to, defined benefit or defined contribution plans. Excludes other postretirement benefits. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 45 -Paragraph 28 -Subparagraph (a) -SubTopic 10 -Topic 230 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482740/230-10-45-28 + Details
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