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Other Long-Term Assets Other Long-Term Assets (Details) - USD ($) $ in Millions | 12 Months Ended |
--- | --- | ---
Sep. 30, 2018 | Sep. 30, 2017
Other Long-Term Assets |  |
EnergyRight receivables | $ 112 | $ 127
Total other long-term assets | $ 349 | 323
Energy Right |  |
Other Long-Term Assets |  |
Number of days in default | 180 days |
Accounts Receivable [Member] |  |
Other Long-Term Assets |  |
EnergyRight receivables | $ 22 | 25
Other long-term assets |  |
Other Long-Term Assets |  |
EnergyRight receivables | 90 | 100
Loans and other long-term receivables, net | 135 | 115
Commodity contract derivative assets | 31 | 2
Prepaid capacity payments | 27 | 34
Other | $ 66 | $ 72
Minimum | Energy Right |  |
Other Long-Term Assets |  |
EnergyRight loan terms | 5 years |
Maximum | Energy Right |  |
Other Long-Term Assets |  |
EnergyRight loan terms | 10 years |

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- Definition Carrying amount as of the balance sheet date of the asset arising from commodity contracts such as futures contracts tied to the movement of a particular commodity, which are expected to be converted into cash or otherwise disposed of after a year or beyond the normal operating cycle, if longer. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.17) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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