Inventories (Schedule of Inventories) (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Inventory, Net [Abstract]
Separative work units inventory	$ 8.8	$ 17.0
Uranium inventory	82.3	47.8
Inventories	91.1	64.8
Separative work units owed to customers and suppliers	0.0	4.6
Uranium owed to customers and suppliers	8.4	0.3
Inventories owed to customers and suppliers	8.4	4.9
Separative work units net of liability	8.8	12.4
Uranium inventory net of liability	73.9	47.5
Inventories, net	$ 82.7	$ 59.9

Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

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