Deferred Contractual Obligations (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2011
Loss Contingency, Information about Litigation Matters [Abstract]
Court of Federal Claims Ruling To CYAPC	$ 34.2
Court Of Federal Claims Ruling To YAEC	32.9
Court Of Federal Claims Ruling To MYAPC	75.8
Trial Court Ruling To CYAPC	39.7
Trial Court Ruling To YAEC	21.2
Trial Court Ruling To MYAPC	$ 81.7

Amount that the Court of Federal Claims ruled the DOE was liable to CYAPC on October 4, 2006.

No definition available.

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Amount that the Court of Federal Claims ruled the DOE was liable to MYAPC on October 4, 2006.

No definition available.

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Amount that the Court of Federal Claims ruled the DOE was liable to YAEC on October 4, 2006.

No definition available.

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Amount that the Trial Court ruled the DOE was liable to CYAPC on September 9, 2010.

No definition available.

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Amount that the Trial Court ruled the DOE was liable to MYAPC on September 9, 2010.

No definition available.

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Amount that the Trial Court ruled the DOE was liable to YAEC on September 9, 2010.

No definition available.

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