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Risk Management Activities and Derivative Transactions Derivatives Under FTP (Details) (USD $) In Millions, unless otherwise specified |  | 9 Months Ended |  |
--- | --- | --- | --- | ---
Jun. 30, 2014 | Jun. 30, 2014 Swap contracts | Jun. 30, 2014 Coal Contract Derivatives | Sep. 30, 2013 Coal Contract Derivatives
Derivative |  |  |  |
FTP transaction limit | $ 130 |  |  |
Maximum hedge volume | 75.00% |  |  |
Market value limitation of outstanding construction materials hedging transactions | 100 |  |  |
Portfolio value at risk limit for foreign currency transactions | 5 |  |  |
Fair value |  |  | $ 0 | $ 0
Remaining terms |  | 4 years |  |

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- Definition The market value limitation of outstanding hedging transactions involving construction materials. + References No definition available. + Details
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