v3.26.3
Segment Information (Segment Reporting Information) (Details) - USD ($)
$ in Millions
3 Months Ended 9 Months Ended
Sep. 30, 2026
Sep. 30, 2025
Sep. 30, 2026
Sep. 30, 2025
Segment Reporting [Line Items]        
Revenue $ 55.5 $ 74.9 $ 308.3 $ 302.5
Cost of sales 66.1 79.2 237.5 220.0
Advanced technology license and decommissioning costs 4.7 1.7 34.4 8.0
Selling, general and administrative 13.2 9.5 49.4 31.2
Intangible Asset, Finite-Lived, Amortization Expense 1.2 1.1 5.5 5.9
Nonoperating components of net periodic benefit expense (income) 1.0 1.0 3.0 2.9
Interest expense 3.6 3.2 10.8 8.8
Investment income (16.9) (12.9) (50.2) (28.2)
Other Nonoperating Income 0.0 (0.1) 0.2 0.0
Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest 28.7 (8.0) 62.8 64.6
Gross Profit (10.6) (4.3) $ 70.8 82.5
NumberOfReportableSegmentsNotDisclosedFlag     true  
Low Enriched Uranium Segment [Member]        
Segment Reporting [Line Items]        
Cost of sales 38.7 59.0 $ 161.8 158.4
Low Enriched Uranium Segment [Member] | Operating Segments        
Segment Reporting [Line Items]        
Gross Profit (6.9) (7.9) 74.8 75.8
Technical Solutions Segment [Member] | Operating Segments        
Segment Reporting [Line Items]        
Revenue 55.5 81.2 315.1 314.9
Cost of sales 66.1 85.6 242.1 230.7
Gross Profit (3.7) 3.5 (1.8) 8.4
Product [Member]        
Segment Reporting [Line Items]        
Revenue 31.8 44.8 229.8 221.8
Cost of sales 38.7 52.6 157.2 147.7
Product [Member] | Low Enriched Uranium Segment [Member]        
Segment Reporting [Line Items]        
Revenue 31.8 51.1 236.6 234.2
Gross Profit (6.9) (7.8) 72.6 74.1
Product [Member] | Low Enriched Uranium Segment [Member] | Intersegment Eliminations        
Segment Reporting [Line Items]        
Revenue 0.0 6.3 6.8 12.4
Cost of sales 0.0 6.4 4.6 10.7
Gross Profit 0.0 (0.1) 2.2 1.7
Separative Work Units [Member]        
Segment Reporting [Line Items]        
Revenue 14.1 10.7 155.7 187.7
Uranium [Member]        
Segment Reporting [Line Items]        
Revenue 17.7 34.1 74.1 34.1
Service [Member]        
Segment Reporting [Line Items]        
Revenue 23.7 30.1 78.5 80.7
Cost of sales 27.4 26.6 80.3 72.3
Gross Profit (3.7) 3.5 (1.8) 8.4
Service [Member] | Intersegment Eliminations        
Segment Reporting [Line Items]        
Revenue 0.0 (6.3) (6.8) (12.4)
Cost of sales 0.0 (6.4) (4.6) (10.7)
Gross Profit $ 0.0 $ 0.1 $ (2.2) $ (1.7)