Deferred Contractual Obligations (Details) (USD $) In Millions, unless otherwise specified	Sep. 30, 2012
Notes To Consolidated Financial Statements [Abstract]
Court Of Federal Claims Ruling To CYAPC	$ 34.2
Court Of Federal Claims Ruling To YAEC	32.9
Court Of Federal Claims Ruling MYAPC	75.8
Trial Court Ruling To CYAPC	39.7
Trial Court Ruling To YAEC	21.2
Trial Court Ruling To MYAPC	81.7
Court Of Federal Appeals Ruling Increase To YAEC Damages	$ 17.0

The amount by which the Court of Federal Appeals increased damages in favor of YAEC by in 2012.

No definition available.

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Amount that the Court of Federal Claims deeded the DOE liable to MYAPC for in 2006.

No definition available.

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Amount of the 2006 Court of Federal Claims ruled in favor of CYAPC

No definition available.

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The amount the Court of Federal Claims deemed the DOE was liable to YAEC in 2006.

No definition available.

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Amount that the Trial Court ruled in favor of CYAPC in 2010.

No definition available.

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Amount that the Trial Court ruled in favor of MYAPC for in 2010.

No definition available.

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Period Type:	instant

Amount that the Trial Court ruled in favor of YAEC for in 2010.

No definition available.