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Contingencies and Legal Proceedings Contingencies (Details) $ in Millions | 6 Months Ended |
--- | --- | ---
Mar. 31, 2018 USD ($) reactors Insurance_layers Procedures | Sep. 30, 2017 USD ($)
Loss Contingencies |  |
Nuclear liability insurance | $ 450 |
Assessment from licensees for each licensed reactor | $ 127 |
Number of licensed reactors in US | reactors | 100 |
Nuclear accident assessment limitation per year per unit | $ 19 |
Maximum assessment per nuclear incident | 891 |
Maximum payment required per accident in any one year | 133 |
Total amount of protection available | $ 13,000 |
Surcharge for legal expenses | 5.00% |
Number of layers before Congress is required to take action | Insurance_layers | 2 |
Amount of property, decommissioning, and decontamination insurance carried | $ 5,100 |
Amount of insurance available for loss at any one site | 2,100 |
Maximum amount of retrospective premiums | 126 |
Maximum idemnity if a covered accident takes or keeps a nuclear unit offline | 490 |
Maximum retrospective premiums | 43 |
Estimated future decommissioning cost | $ 4,389 | $ 4,304
Number of procedures for determining estimates for the costs of nuclear decommissioning | Procedures | 2 |
Possible additional future costs for compliance with Clean Air Act requirements | $ 165 |
Possible additional future costs for compliance with CCR requirements | 1,200 |
Possible additional future costs for compliance with Clean Water requirements. | 500 |
Estimated liability for cleanup and environmental work | 10 | 7
Nuclear |  |
Loss Contingencies |  |
Estimated future decommissioning cost | 2,924 | 2,859
Non-nuclear |  |
Loss Contingencies |  |
Estimated future decommissioning cost | $ 1,465 | $ 1,445

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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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- Definition The amount of property, decommissioning, and decontamination insurance carried for nuclear plants owned to cover the cost of stabilizing or shutting down a reactor after an accident. + References No definition available. + Details
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- Definition An assessment from licensees for each licensed nuclear reactor in the United States to fund the second layer, the Secondary Financial Program. + References No definition available. + Details
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- Definition Maximum assessment per nuclear incident. + References No definition available. + Details
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- Definition The maximum idemnity per unit if an accident covered by the policy tasks or keeps a nuclear unit offline. + References No definition available. + Details
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- Definition The maximum payment that would be required per accident in any one year. + References No definition available. + Details
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- Definition The maximum amount of retrospective premiums that may be required for property, decommissioning, and decontamination insurance. + References No definition available. + Details
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- Definition The per year per unit limitation of the assessment for any nuclear accident + References No definition available. + Details
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- Definition For the first layer of protection all NRC nuclear plant licensees purchase nuclear insurance from American Nuclear Insurers for each nuclear plant with an operating license. + References No definition available. + Details
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- Definition Number of procedures for determining estimates for the costs of nuclear decommissioning + References No definition available. + Details
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- Definition The possible additional future costs for compliance with Clean Air Act requirements. + References No definition available. + Details
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- Definition The maximum amount of retrospective premiums that could be required for accidental outage insurance. + References No definition available. + Details
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- Definition The total amount of protection available to compensate for losses arising from a nuclear event in the United States. + References No definition available. + Details
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- Definition The U.S. Congress is required to take action to provide additional funds to cover the additional losses if these layes are exhausted. + References No definition available. + Details
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- Definition Undiscounted amount of the accrual for environmental loss contingencies. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 5.Y.Q1) -URI http://asc.fasb.org/extlink&oid=27011672&loc=d3e149879-122751 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 410 -SubTopic 30 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=6393242&loc=d3e13207-110859 + Details
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