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Commitment and Contingencies (Details) (USD $) In Millions, except Per Share data, unless otherwise specified |  | 6 Months Ended | 9 Months Ended
--- | --- | --- | ---
Jun. 30, 2014 | Mar. 31, 2015 Scenario, Forecast [Member] | Sep. 30, 2014 Scenario, Forecast [Member]
ACTDO DOE Funding – Increment 1 |  |  | $ 33.7
ACTDO DOE Funding – Exercised Contract Total |  |  | 75.3
ACTDO DOE Funding – Monthly |  | 6.9 | 6.7
ACTDO DOE Funding – Option |  | 41.7 |
ACTDO DOE Funding – Total |  | 117 |
NYSE 30-day Average Minimum Market Capitalization | 50 |  |
NYSE Minimum 30 Day Average Closing Price | $ 1.00 |  |
NYSE Market Capitalization Subject to Suspension | 15 |  |
PBGC estimate of potential Portsmouth pension liability | $ 130 |  |
Minimum Paducah SWU Production Under 2002 DOE-USEC Agreement | 3,500,000 |  |

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