Name:	us-gaap_CommitmentsAndContingenciesDisclosureAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

Carrying amount of long-term debt, net of unamortized discount or premium, excluding amounts to be repaid within one year or the normal operating cycle, if longer (current maturities). Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

Commitment and Contingencies (Details) (USD $)	19 Months Ended
Commitment and Contingencies (Details) (USD $)	Dec. 31, 2013	Sep. 30, 2013	Dec. 31, 2012	Sep. 30, 2012	Dec. 31, 2011
Commitments and Contingencies Disclosure [Abstract]
Maximum funding for RD&D Program - Revised Estimate	$ 320,000,000
RD&D Program Funding by DOE	80.00%
RD&D Program Funding by USEC	20.00%
RD&D Program Funding by DOE To Date	241,300,000
RD&D Program Funding by DOE - Increment 5	13,600,000
Amount of application under DOE Loan Guarantee Program		2,000,000,000
Potential financing from Japanese export credit agencies under discussion		1,000,000,000
Minimum additional financing needed for ACP beyond DOE and Japanese		1,000,000,000
NYSE 30-day average minimum market capitalization		50,000,000
NYSE Minimum 30 Day Average Closing Price		$ 1.00
NYSE 30-Day Market Capitalization Subject to Suspension		15,000,000
Stockholders’ Equity (Deficit)		(462,100,000)	(472,900,000)	652,200,000	752,400,000
PBGC estimate of potential Portsmouth pension liability		130,000,000
Long-Term Debt		$ 530,000,000	$ 530,000,000
Minimum Paducah SWU Production Under 2002 DOE-USEC Agreement		3,500,000