Consolidated Balance Sheets Consolidated Balance Sheets Parenthetical (USD $) In Thousands, except Share data, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Nuclear fuel; fuel in process	$ 37,294	$ 56,129
Allowance for Doubtful Accounts Receivable, Current	$ 2,799	$ 2,906
Common Stock, Par or Stated Value Per Share	$ 1	$ 1
Common Stock, Shares Authorized	100,000,000	100,000,000
Common Stock, Shares, Issued	65,625,339	65,520,551
Common stock, restricted shares	121,363	84,446
Treasury Stock, Shares	25,492,919	25,492,919