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Inventories (Narrative) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Dec. 31, 2013
Inventory, Net [Abstract]
Inventories provided by customers and suppliers	$ 954	$ 1,300
Decline in Uranium Spot Price Indicator	3.00%
Decline in Uranium Quantities Provided by Customers and Suppliers	23.00%

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Decline in Uranium Quantities Provided by Customers and Suppliers

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Decline in Uranium Spot Price Indicator

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Uranium held by USEC to which title was held by customers and suppliers and for which no assets or liabilities were recorded on the balance sheet

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