Commitment and Contingencies (Details) (USD $)	Jun. 30, 2011	Dec. 31, 2010
Commitments and Contingencies
Amount of application under DOE Loan Guarantee Program	$ 2,000,000,000
Maximum investment under securities purchase agreement	200,000,000
Maximum investment under securities purchase agreement, each party	100,000,000
First installment under securities purchase agreement, total	75,000,000
Second installment under securities purchase agreement, total (planned)	50,000,000
Potential financing from Japanese export credit agencies under discussion	1,000,000,000
Minimum annual SWU capacity for American Centrifuge Plant under 2002 DOE-USEC milestone agreement	3,500,000
Estimated maximum potential severance liability	2,000,000	25,000,000
Estimated maximum potential severance liability, DOE share		$ 18,500,000

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Amount of application under DOE Loan Guarantee Program

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First installment under securities purchase agreement, total

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Maximum investment under securities purchase agreement

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Maximum investment under securities purchase agreement, each party

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Maximum potential severance liability

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Maximum potential severance liability shared by others (DOE)

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Minimum annual SWU capacity for American Centrifuge Plant under 2002 DOE-USEC milestone agreement

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Potential financing from Japanese export credit agencies under discussion

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Second installment under securities purchase agreement, total

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