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Contingencies and Legal Proceedings Legal Proceedings (Details) $ in Millions | 6 Months Ended
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Mar. 31, 2018 USD ($) People megawatts Groups Units Years Agreements
General |
Legal Proceedings |
Legal loss contingency accrual | $ 18
Environmental Agreements |
Legal Proceedings |
Number of similar environmental agreements entered into | Agreements | 2
Number of environmental agreements entered into with the EPA | Agreements | 1
Number of environmental agreements entered into with environmental advocacy groups | Groups | 3
Number of units to be idled | Units | 18
Megawatts | megawatts | 2,200
Megawatts option 2 | 3,500
Amount to be invested in certain TVA environmental projects | $ 290
Amount to be provided to fund environmental projects | 60
Amount to pay civil penalties | $ 10
Case Involving Tennessee Valley Authority Retirement System |
Legal Proceedings |
Number of participants that filed suit | People | 8
Contribution from TVA | $ 1,000
Retirement age of eligibility for cost of living adjustment before January 1, 2010 | Years | 55
Retirement age of eligibility for cost of living adjustment after January 1, 2010 | Years | 60
Other long-term liabilities | General |
Legal Proceedings |
Legal loss contingency accrual | $ 11
Accounts payable and accrued liabilities | General |
Legal Proceedings |
Legal loss contingency accrual | $ 7

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