XML 40 R50.htm IDEA: XBRL DOCUMENT v2.4.0.8
Accounts Receivable (Details) (USD $)
In Millions, unless otherwise specified
Mar. 31, 2014
Dec. 31, 2013
Dec. 31, 2012
Accounts, Notes, Loans and Financing Receivable [Line Items]      
Utility Customer Receivables $ 6.2 $ 129.3  
DOE pro-rata share of Cooperative Agreement funding 17.5 20.1  
Contract Services Billed Revenue 16.2 15.7  
Contract Services Unbilled Revenue 2.7 1.9  
Contract Services Customer Receivables 18.9 17.6  
Accounts Receivable, Gross, Current 42.6 167.0  
Allowance for Doubtful Accounts Receivable 4.6 4.0  
Accounts Receivable, Net 38.0 163.0  
Accounts Receivable, Gross, Noncurrent     38.0
Government [Member]
      
Accounts, Notes, Loans and Financing Receivable [Line Items]      
Allowance for Doubtful Accounts Receivable 55.0 55.0  
Accounts Receivable, Gross, Noncurrent 80.8 80.8  
Accounts Receivable, Net, Noncurrent $ 25.8 $ 25.8