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Increase (Decrease) in ARO Due to Changes in Assumed Retirement Dates

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Increase (Decrease) in ARO Due to Updated Cost Escalation Rates and Discount Rates

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Increase (Decrease) in ARO Due to Updated Timing Assumptions

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Increase (Decrease) in Utilities Operating Expense Maintenance Operations And Other Costs And Expenses

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Amount of increase (decrease) in asset retirement obligations.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 410
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481850/410-20-50-1

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Decommission fund to pay for the costs of decontaminating and decommissioning of facilities through collection of revenues derived from utility assessments and government appropriations. Decommission fund investment for the process whereby a power station, at the end of its economic life, is taken permanently out of service and its site made available for other purposes. In the case of a nuclear station this comprises three different states of clearance. Immediately after the final closure, radioactive material such as nuclear fuel and operational waste is removed and the buildings surrounding the reactor shield are dismantled and finally the reactor itself is dismantled.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(12))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

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Nuclear Decommissioning - Narrative (Details) - USD ($)	3 Months Ended		9 Months Ended
Nuclear Decommissioning - Narrative (Details) - USD ($)	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023
Asset Retirement Obligations [Line Items]
Nuclear decommissioning trust funds	$ 17,694,000,000		$ 17,694,000,000		$ 16,398,000,000
Nuclear Decommissioning
Asset Retirement Obligations [Line Items]
Net decrease due to changes in, and timing of, estimated future cash flows			2,275,000,000
Net decrease due to changes in assumed retirement dates			(2,940,000,000)
Net decrease related to changes in timing assumptions			(138,000,000)
Net increase due to increase in cost escalation rates and lower discount rates			803,000,000
Net increase (decrease) in operating and maintenance expense	78,000,000	$ 68,000,000	78,000,000	$ 68,000,000
Assets, Total
Asset Retirement Obligations [Line Items]
Nuclear decommissioning trust funds	17,798,000,000		17,798,000,000		16,398,000,000
Other Current Assets
Asset Retirement Obligations [Line Items]
Nuclear decommissioning trust funds	$ 104,000,000		$ 104,000,000		$ 0