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Contingencies and Legal Proceedings Contingencies (Details) $ in Millions | 6 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2025 USD ($) Insurance_layers Procedures reactors | Sep. 30, 2024 USD ($)
Loss Contingencies |  |
Nuclear liability insurance | $ 500 |
Assessment from licensees for each licensed reactor | $ 166 |
Number of licensed reactors in US | reactors | 95 |
Nuclear accident assessment limitation per year per unit | $ 25 |
Maximum assessment per nuclear incident | 1,200 |
Total amount of protection available | 16,300 |
Amount of insurance available for loss at any one site | 2,100 |
Maximum amount of retrospective premiums | 115 |
Maximum idemnity if a covered accident takes or keeps a nuclear unit offline | 490 |
Maximum retrospective premiums | 44 |
Estimated future decommissioning cost | $ 10,878 | $ 10,806
Number of procedures for determining estimates for the costs of nuclear decommissioning | Procedures | 2 |
Estimated liability for cleanup and environmental work | $ 10 | 15
Amount of insurance available for loss at any one site (top range) | 2,800 |
Long-term debt of VIEs, net (including current maturities) | $ 1,702 | $ 966
The U.S. Congress is required to take action if these layes are exhausted | Insurance_layers | 2 |
Environmental Remediation |  |
Loss Contingencies |  |
Accrual for Environmental Loss Contingencies, Significant Assumptions | 276 million | 215 million
Accrual for Environmental Loss Contingencies, Significant Assumptions | 276 million | 215 million
Nuclear |  |
Loss Contingencies |  |
Estimated future decommissioning cost | $ 3,893 | $ 3,814
Non-nuclear |  |
Loss Contingencies |  |
Estimated future decommissioning cost | $ 6,985 | $ 6,992

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- Definition The amount of property, decommissioning, and decontamination insurance available for loss at any one site to cover the cost of stabilizing or shutting down a reactor after an accident. + References No definition available. + Details
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