Debt Disclosure [Abstract] Summary of Deferred Financing Costs Summary of Deferred Financing Costs Summary of Deferred Financing Costs Research and Development [Abstract] Statement [Table] Statement [Table] Customer [Axis] Customer [Axis] Customer [Domain] Customer [Domain] Government [Member] Government [Member] Scenario [Axis] Scenario [Axis] Scenario, Unspecified [Domain] Scenario, Unspecified [Domain] Scenario, Forecast [Member] Scenario, Forecast [Member] Scenario, Actual [Member] Scenario, Actual [Member] Statement [Line Items] Statement [Line Items] RD&D Program Qualifying Expenditures - DOE Share Other Operating Income Maximum RD&D Program Funding by DOE Maximum RD&D Program Funding by DOE Maximum RD&D Program Funding by DOE RD&D Program Funding by DOE RD&D Program Funding by DOE RD&D Program Funding by DOE RD&D Program Funding by USEC RD&D Program Funding by USEC RD&D Program Funding by DOE RD&D Program Qualifying Expenditures RD&D Program Qualifying Expenditures To Date RD&D Program Qualifying Expenditures To Date RD&D Program Qualifying Expenditures - DOE Share RD&D Program Qualifying Expenditures To Date - DOE Share RD&D Program Qualifying Expenditures To Date - DOE Share RD&D Program Qualifying Expenditures – USEC Share RD&D Program Qualifying Expenditures – USEC Share RD&D Program Qualifying Expenditures – USEC Share RD&D Program Qualifying Expenditures To Date - DOE Share - Receivable RD&D Program Qualifying Expenditures To Date - DOE Share - Receivable RD&D Program Qualifying Expenditures To Date - DOE Share - Receivable Other advanced technology costs Other Research and Development Expense Statement of Cash Flows [Abstract] Predecessor [Member] Predecessor [Member] Successor [Member] Successor [Member] Cash Flows from Operating Activities Net Cash Provided by (Used in) Operating Activities, Continuing Operations [Abstract] Net income (loss) Net Income (Loss) Attributable to Parent Adjustments to reconcile net income (loss) to net cash (used in) operating activities: Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] Depreciation and amortization Depreciation, Depletion and Amortization Immediate recognition of net actuarial loss Defined Benefit Plan, Amortization of Gains (Losses) Reorganization items, non-cash Other Noncash Expense Transfers and retirements of machinery and equipment Gain (Loss) on Disposition of Property Plant Equipment, Excluding Oil and Gas Property and Timber Property Convertible preferred stock dividends payable-in-kind Other Noncash Income (Expense) Gain on sales of assets and subsidiary Gain (Loss) on Disposition of Business Inventory valuation adjustments Asset Impairment Charges Changes in operating assets and liabilities: Increase (Decrease) in Operating Liabilities [Abstract] Accounts receivable – (increase) decrease Increase (Decrease) in Accounts Receivable Inventories, net – (increase) decrease Increase (Decrease) in Inventories Payables under Russian Contract – increase (decrease) Increase (Decrease) in Accounts Payable, Trade Deferred revenue, net of deferred costs – increase (decrease) Increase (Decrease) in Deferred Revenue Accounts payable and other liabilities – (decrease) Increase (Decrease) in Accounts Payable and Accrued Liabilities Accrued depleted uranium disposition - increase (decrease) Increase (Decrease) in Other Accrued Liabilities Other, net Increase (Decrease) in Other Operating Assets and Liabilities, Net Net Cash (Used in) Operating Activities Net Cash Provided by (Used in) Operating Activities Cash Flows Provided by Investing Activities Net Cash Provided by (Used in) Investing Activities [Abstract] Deposits for surety bonds - net (increase) decrease Increase (Decrease) in Restricted Cash Proceeds from sales of assets and subsidiary Proceeds from Divestiture of Businesses Net Cash Provided by Investing Activities Net Cash Provided by (Used in) Investing Activities Cash Flows Used in Financing Activities Net Cash Provided by (Used in) Financing Activities [Abstract] Repayment of credit facility term loan Repayments of Debt, Maturing in More than Three Months Payments for deferred financing costs Payments of Financing Costs Common stock issued (purchased), net Proceeds from (Repurchase of) Equity Net Cash (Used in) Financing Activities Net Cash Provided by (Used in) Financing Activities Net (Decrease) Cash and Cash Equivalents, Period Increase (Decrease) Cash and Cash Equivalents at Beginning of Period Cash and Cash Equivalents, at Carrying Value Cash and Cash Equivalents at End of Period Supplemental Cash Flow Information: Supplemental Cash Flow Information [Abstract] Interest paid Interest Paid, Net Income taxes paid, net of refunds Income Taxes Paid Defined Benefit Plan, Information about Plan Assets [Abstract] Fair Value, Hierarchy [Axis] Fair Value, Hierarchy [Axis] Fair Value Hierarchy [Domain] Fair Value Hierarchy [Domain] Fair Value, Inputs, Level 1 [Member] Fair Value, Inputs, Level 1 [Member] Fair Value, Inputs, Level 2 [Member] Fair Value, Inputs, Level 2 [Member] Fair Value, Inputs, Level 3 [Member] Fair Value, Inputs, Level 3 [Member] Defined Benefit Plans and Other Postretirement Benefit Plans [Axis] Defined Benefit Plans and Other Postretirement Benefit Plans [Axis] Defined Benefit Plan and Other Postretirement Benefit Plan [Domain] Defined Benefit Plan and Other Postretirement Benefit Plan [Domain] Pension Plan, Defined Benefit [Member] Pension Plan [Member] Other Postretirement Benefit Plan, Defined Benefit [Member] Other Postretirement Benefit Plan [Member] Money Market Funds Money Market Funds Money Market Funds Bond Mutual Funds Bond Mutual Funds Bond Mutual Funds Equity Mutual Funds Equity Mutual Funds Equity Mutual Funds US Government Securities US Government Securities, at Carrying Value Collective Trust - Money Market Funds Money Market Funds, at Carrying Value Collective Trust - Bond Funds Collective Trust Bond Funds Collective Trust Bond Funds Collective Trust - Equity Funds Collective trust - equity funds Collective trust - equity funds Corporate Debt Corporate debt Corporate debt Municipal Bonds Municipal Debt Securities, at Carrying Value Fair Value of Investments by Hierarchy Level Fair value of investments by hierarchy level Fair value of investments by hierarchy level Accrued Interest Receivable Accrued interest receivable Accrued interest receivable Unsettled Transactions Receivable Unsettled transactions receivable Unsettled transactions receivable Defined Benefit Plan, Fair Value of Plan Assets Defined Benefit Plan, Fair Value of Plan Assets Accounts Payable and Accrued Liabilities [Abstract] Schedule of Accounts Payable and Accrued Liabilities [Table Text Block] Schedule of Accounts Payable and Accrued Liabilities [Table Text Block] Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases, (Sales), Issuances, (Settlements) [Abstract] Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3 Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3 Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3 Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3 Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract] Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Discount Rate Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Discount Rate Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Expected Long-term Return on Assets Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Expected Long-term Return on Assets Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Rate of Compensation Increase Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Rate of Compensation Increase Advanced Technology Costs and Other Income Research, Development, and Computer Software Disclosure [Text Block] Reorganizations Items, Net [Abstract] Reorganizations Items, Net [Abstract] Reorganization items, professional fees Debtor Reorganization Items, Legal and Advisory Professional Fees Reorganization items, expense of deferred financing costs Debtor Reorganization Items, Write-off of Deferred Financing Costs and Debt Discounts Gain on cancellation of convertible senior notes, net Gain on cancellation of convertible senior notes, net Gain on cancellation of convertible senior notes, net Gain on cancellation of convertible preferred stock, net Gain on cancellation of convertible preferred stock, net Gain on cancellation of convertible preferred stock, net Expense of unamortized restricted stock Expense of unamortized restricted stock Expense of unamortized restricted stock Gain related to the freeze of SERP benefits Gain related to the freeze of SERP benefits Gain related to the freeze of SERP benefits Revaluation of deferred revenue, net of deferred costs Revaluation of deferred revenue, net of deferred costs Revaluation of deferred revenue, net of deferred costs Revaluation of inventory Revaluation of inventory Revaluation of inventory Valuation of intangible assets Valuation of intangible assets Valuation of intangible assets Remeasurement of pension and postretirement benefit obligations Remeasurement of pension and postretirement benefit obligations Remeasurement of pension and postretirement benefit obligations Elimination of Predecessor Company accumulated other comprehensive loss related to pension and postretirement benefit obligations Elimination of Predecessor Company accumulated other comprehensive loss related to pension and postretirement benefit obligations Elimination of Predecessor Company accumulated other comprehensive loss related to pension and postretirement benefit obligations Reorganization items, net Reorganization Items Reorganization items, net, paid Reorganization Items, Net, Paid Reorganization Items, Net, Paid Accrued professional fees, current Accrued Professional Fees, Current Defined Benefit Plan, Assumed Health Care Cost Trend Rates [Abstract] Defined Benefit Plan, Health Care Cost Trend Rate Assumed for Next Fiscal Year Defined Benefit Plan, Health Care Cost Trend Rate Assumed for Next Fiscal Year Defined Benefit Plan, Ultimate Health Care Cost Trend Rate Defined Benefit Plan, Ultimate Health Care Cost Trend Rate Defined Benefit Plan, Year that Rate Reaches Ultimate Trend Rate Defined Benefit Plan, Year that Rate Reaches Ultimate Trend Rate Discontinued Operation, Additional Disclosures [Abstract] Schedule of Discontinued Operations Income Statement Disclosures [Table Text Block] Schedule of Disposal Groups, Including Discontinued Operations, Income Statement, Balance Sheet and Additional Disclosures [Table Text Block] Reorganization Items, Net [Text Block] Reorganization Items, Net [Text Block] Reorganization Items, Net [Text Block] Fair Value Disclosures [Abstract] Fair Value, Assets and Liabilities Measured on Nonrecurring Basis, Disclosure Items [Axis] Fair Value, Assets and Liabilities Measured on Nonrecurring Basis, Disclosure Items [Domain] Level 2 [Member] Cash equivalents Cash and Cash Equivalents, Fair Value Disclosure Deferred compensation asset Cash Surrender Value, Fair Value Disclosure Deferred compensation obligation Obligations, Fair Value Disclosure Share-based Compensation [Abstract] Share-based Goods and Nonemployee Services Transaction, Valuation Method, Risk Free Interest Rate Share-based Goods and Nonemployee Services Transaction, Valuation Method, Risk Free Interest Rate Share-based Goods and Nonemployee Services Transaction, Valuation Method, Expected Volatility Rate Share-based Goods and Nonemployee Services Transaction, Valuation Method, Expected Volatility Rate Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term, Simplified Method Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term, Simplified Method Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross Income Tax Disclosure [Abstract] Liability for Uncertain Tax Positions, Noncurrent Liability for Uncertain Tax Positions, Noncurrent Unrecognized Tax Benefits, Decrease Resulting from Prior Period Tax Positions Unrecognized Tax Benefits, Decrease Resulting from Prior Period Tax Positions Stock-Based Compensation Disclosure of Compensation Related Costs, Share-based Payments [Text Block] Earnings Per Share [Abstract] Schedule of Long-term Debt Instruments [Table] Schedule of Long-term Debt Instruments [Table] Long-term Debt, Type [Axis] Long-term Debt, Type [Axis] Long-term Debt, Type [Domain] Long-term Debt, Type [Domain] Convertible Debt [Member] Convertible Debt [Member] Debt Instrument [Line Items] Debt Instrument [Line Items] Net (loss) from continuing operations Income (Loss) from Continuing Operations, Including Portion Attributable to Noncontrolling Interest Income from discontinued operations Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Parent Interest expense Interest Expense, Debt Net income (loss) if converted - diluted Net Income (Loss) Attributable to Parent, Diluted Weighted average common shares Weighted Average Number of Shares Issued, Basic Less: Weighted average unvested restricted stock Weighted Average Number of Shares, Restricted Stock Denominator for basic calculation Weighted Average Number of Shares Outstanding, Basic Convertible notes Incremental Common Shares Attributable to Dilutive Effect of Conversion of Debt Securities Convertible preferred stock - equivalent common shares Total Common Shares Attributable To Conversion Of Debt Securities Total Common Shares Attributable To Conversion Of Debt Securities Convertible preferred stock - less: share issuance limitation Unallowable Common Shares Attributable To Conversion Of Debt Securities Unallowable Common Shares Attributable To Conversion Of Debt Securities Convertible preferred stock - net allowable shares Incremental Common Shares Attributable to Dilutive Effect of Conversion of Preferred Stock Subtotal Unadjusted weighted average effect of dilutive securities Unadjusted weighted average effect of dilutive securities Less: shares excluded in a period of net loss or antidilution Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount Weighted average effect of dilutive securities Weighted Average Number Diluted Shares Outstanding Adjustment Denominator for diluted calculation Weighted Average Number of Shares Outstanding, Diluted Income (loss) from continuing operations - per basic share Income (Loss) from Continuing Operations, Per Basic Share Income (loss) from continuing operations - per diluted share Income (Loss) from Continuing Operations, Per Diluted Share Income per share from discontinued operations - basic and diluted Income (Loss) from Discontinued Operations and Disposal of Discontinued Operations, Net of Tax, Per Basic and Diluted Share Net income (loss) per basic share Earnings Per Share, Basic Net income (loss) per diluted share Earnings Per Share, Diluted Schedule of Components of Income Tax Expense (Benefit) [Table Text Block] Schedule of Components of Income Tax Expense (Benefit) [Table Text Block] Schedule of Deferred Tax Assets and Liabilities [Table Text Block] Schedule of Deferred Tax Assets and Liabilities [Table Text Block] Schedule of Effective Income Tax Rate Reconciliation [Table Text Block] Schedule of Effective Income Tax Rate Reconciliation [Table Text Block] Summary of Income Tax Contingencies [Table Text Block] Summary of Income Tax Contingencies [Table Text Block] Quarterly Results of Operations (Unaudited) [Abstract] Quarterly Results of Operations (Unaudited) [Abstract] Quarterly Financial Information [Text Block] Quarterly Financial Information [Text Block] CONDENSED CONSOLIDATED BALANCE SHEET (Parenthetical) [Abstract] CONDENSED CONSOLIDATED BALANCE SHEET (Parenthetical) [Abstract] Class of Stock [Axis] Class of Stock [Axis] Class of Stock [Domain] Class of Stock [Domain] Preferred Stock, Par or Stated Value Per Share Preferred Stock, Par or Stated Value Per Share Preferred Stock, Shares Authorized Preferred Stock, Shares Authorized Preferred Stock, Shares Issued Preferred Stock, Shares Issued Common Stock, Par or Stated Value Per Share Common Stock, Par or Stated Value Per Share Common Stock, Shares Authorized Common Stock, Shares Authorized Common Stock, Shares, Issued Common Stock, Shares, Issued Treasury Stock, Shares Treasury Stock, Shares Summary of Significant Accounting Policies [Abstract] Summary of Significant Accounting Policies [Abstract] Significant Accounting Policies [Text Block] Significant Accounting Policies [Text Block] Restricted Stock or Unit Expense Restricted Stock or Unit Expense Stock or Unit Option Plan Expense Stock or Unit Option Plan Expense Allocated Share-based Compensation Expense Allocated Share-based Compensation Expense Accounts Receivable, Net, Current [Abstract] Schedule of Accounts, Notes, Loans and Financing Receivable [Table] Schedule of Accounts, Notes, Loans and Financing Receivable [Table] Legal Entity of Counterparty, Type [Axis] Legal Entity of Counterparty, Type [Axis] Legal Entity Type of Counterparty [Domain] Legal Entity Type of Counterparty [Domain] Corporation [Member] Corporation [Member] Government - portion related to retiree benefits [Member] Government - portion related to retiree benefits [Member] Government - portion related to retiree benefits [Member] Government - portion related to duplicative credit [Member] Government - portion related duplicative credit [Member] Government - portion related duplicative credit [Member] Accounts, Notes, Loans and Financing Receivable [Line Items] Accounts, Notes, Loans and Financing Receivable [Line Items] Valuation allowance and allowance for doubtful accounts Allowance for Doubtful Accounts Receivable Accounts Receivable, Gross, Noncurrent Accounts Receivable, Gross, Noncurrent Proceeds from DOE on Claims Proceeds from Customers Accounts Receivable, Net, Noncurrent Accounts Receivable, Net, Noncurrent Other long-term liabilities Other Liabilities, Noncurrent Range [Axis] Range [Axis] Range [Domain] Range [Domain] Maximum [Member] Maximum [Member] Debt Instrument [Axis] Debt Instrument [Axis] Debt Instrument, Name [Domain] Debt Instrument, Name [Domain] PIK toggle notes [Member] PIK toggle notes [Member] PIK toggle notes [Member] Long-term debt Long-term Debt Debt instrument interest rate Debt Instrument, Interest Rate, Stated Percentage Debt Interest Rate, PIK Debt Interest Rate, PIK Debt Interest Rate, PIK Interest Payable Interest Payable Interest Payable, Current Interest Payable, Current Interest Payable, Noncurrent Accounts Payable and Accrued Liabilities, Noncurrent Statement of Stockholders' Equity [Abstract] Equity Components [Axis] Equity Components [Axis] Equity Component [Domain] Equity Component [Domain] Common Stock Par Value $.10 per Share [Member] Common Stock [Member] Excess of Capital over Par Value [Member] Additional Paid-in Capital [Member] Retained Earnings (Deficit) [Member] Retained Earnings [Member] Treasury Stock [Member] Treasury Stock [Member] Accumulated Other Comprehensive Income (Loss) [Member] Accumulated Other Comprehensive Income (Loss) [Member] Beginning Balance Stockholders' Equity Attributable to Parent Other comprehensive income, net of tax (Note 20) Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Net Unamortized Gain (Loss) Arising During Period, Net of Tax Restricted and other common stock issued, net of amortization Stock Issued During Period, Value, Share-based Compensation, Net of Forfeitures Restricted Stock Award, Forfeitures Restricted Stock Award, Forfeitures Elimination of Predecessor Company equity Elimination of Predecessor Company equity Elimination of Predecessor Company equity Issuance of Successor Company common stock and excess of capital over par value Issuance of Successor Company common stock and excess of capital over par value Issuance of Successor Company common stock and excess of capital over par value Ending Balance Net Income (Loss) Per Share Earnings Per Share [Text Block] Payments of Financing Costs [Abstract] Statement, Scenario [Axis] Convertible notes, non-current [Member] Convertible notes, non-current [Member] Convertible notes, non-current [Member] Bank credit facilities [Member] Bank Credit Facilities [Member] Bank credit facilities [Member] Convertible notes [Member] Convertible Notes [Member] Convertible notes [Member] Deferred Finance Costs, Beginning Balance Deferred Finance Costs, Noncurrent, Net Deferred financing costs, additions Deferred financing costs, additions Deferred financing costs, additions Deferred financing costs, reductions Deferred financing costs, amortization Deferred financing costs, amortization Deferred Finance Costs, End Balance Stockholders' Equity Attributable to Parent [Abstract] Schedule of Stock by Class [Table] Schedule of Stock by Class [Table] Common Class A [Member] Common Class A [Member] Common Class B [Member] Common Class B [Member] Class of Stock [Line Items] Class of Stock [Line Items] Common Stock, Shares Reserved for Future Issuance Under Management Incentive Plan Common Stock, Capital Shares Reserved for Future Issuance Restructuring and Related Activities [Abstract] Transition Charges Restructuring and Related Activities Disclosure [Text Block] Inventory, Net [Abstract] Inventories Inventory Disclosure [Text Block] Organization, Consolidation and Presentation of Financial Statements [Abstract] Basis of Presentation Organization, Consolidation and Presentation of Financial Statements Disclosure [Text Block] Fresh Start Accounting [Abstract] Fresh Start Accounting [Abstract] Reconciliation Of Enterprise Value To Estimated Fair Value [Table Text Block] Reconciliation Of Enterprise Value To Estimated Fair Value [Table Text Block] Reconciliation Of Enterprise Value To Estimated Fair Value [Table Text Block] Reconciliation Of Enterprise Value To Estimated Reorganization Value [Table Text Block] Reconciliation Of Enterprise Value To Estimated Reorganization Value [Table Text Block] Reconciliation Of Enterprise Value To Estimated Reorganization Value [Table Text Block] Schedule of Fresh-Start Adjustments [Table Text Block] Schedule of Fresh-Start Adjustments [Table Text Block] Schedule Of Cash Payments For Reorganization Adjustments [Table Text Block] Schedule Of Cash Payments For Reorganization Adjustments [Table Text Block] Schedule Of Cash Payments For Reorganization Adjustments [Table Text Block] Schedule Of Cumulative Impact Of Reorganization Adjustments [Table Text Block] Schedule Of Cumulative Impact Of Reorganization Adjustments [Table Text Block] Schedule Of Cumulative Impact Of Reorganization Adjustments [Table Text Block] Schedule Of Allocation of Reorganization Value to Assets [Table Text Block] Schedule Of Allocation of Reorganization Value to Assets [Table Text Block] Schedule Of Allocation of Reorganization Value to Assets [Table Text Block] Schedule Of Cumulative Impact Of Fresh Start Adjustments [Table Text Block] Cumulative Impact Of Fresh Start Adjustments [Table Text Block] Cumulative Impact Of Fresh Start Adjustments [Table Text Block] Components of Deferred Tax Assets and Liabilities [Abstract] Deferred Tax Assets, Plant Lease Turnover and Other Exit Costs Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals, Asset Retirement Obligations Deferred Tax Assets, Employee Benefits Costs Deferred Tax Assets, Tax Deferred Expense, Compensation and Benefits, Employee Benefits Deferred Tax Assets, Inventory Deferred Tax Assets, Inventory Deferred Tax Assets, Property, Plant and Equipment Deferred Tax Assets, Property, Plant and Equipment Deferred Tax Assets, Depleted Uranium and Stored Wastes Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals, Other Deferred Tax Assets, Net Operating Loss and Credit Carryforwards Deferred Tax Assets, Operating Loss Carryforwards Deferred Tax Assets, Accrued Expenses Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals, Accrued Liabilities Deferred Tax Assets, Other Deferred Tax Assets, Tax Deferred Expense, Other Deferred Tax Assets, Gross Deferred Tax Assets, Gross Deferred Tax Assets, Valuation Allowance Deferred Tax Assets, Valuation Allowance Deferred Tax Assets, Net of Valuation Allowance Deferred Tax Assets, Net of Valuation Allowance Deferred Tax Liabilities, Intangible Assets Deferred Tax Liabilities, Intangible Assets Deferred Tax Liabilities, Prepaid Expenses Deferred Tax Liabilities, Deferred Expense, Other Capitalized Costs Deferred Tax Liabilities Deferred Tax Liabilities, Net Sale of NAC Subsidiary Disposal Groups, Including Discontinued Operations, Disclosure [Text Block] Utility Customer Receivables Utility Customer Receivables Utility Customer Receivables DOE pro-rata share of Cooperative Agreement funding Contract Services Customer Receivables Contract Services Customer Receivables Contract Services Customer Receivables Accounts Receivable, Net Accounts Receivable, Net, Current Schedule of Quarterly Financial Information [Table Text Block] Schedule of Quarterly Financial Information [Table Text Block] Restricted Shares, Number of Shares Restricted Shares, Number of Shares Restricted Shares, Number of Shares Restricted Shares, Number of Shares Vested Restricted Shares, Number of Shares Vested Restricted Shares, Number of Shares Vested Restricted Shares, Number of Shares Forfeited Stock Issued During Period, Shares, Restricted Stock Award, Forfeited Restricted Shares, Unvested, Weighted-Average Grant Date Fair Value Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value Restricted Shares, Vested, Weighted-Average Grant Date Fair Value Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value Restricted Shares, Forfeited or Surrendered, Weighted-Average Grant Date Fair Value Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value Effective Income Tax Rate Reconciliation, Deduction, Percent [Abstract] Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent Effective Income Tax Rate Reconciliation, State and Local Income Taxes, Percent Effective Income Tax Rate Reconciliation, State and Local Income Taxes, Percent Effective Income Tax Rate Reconciliation, Tax Exempt Income, Percent Effective Income Tax Rate Reconciliation, Tax Exempt Income, Percent Effective Income Tax Rate Reconciliation, Nondeductible Expense, Percent Effective Income Tax Rate Reconciliation, Nondeductible Expense, Percent Effective Income Tax Rate Reconciliation, Deduction, Other, Percent Effective Income Tax Rate Reconciliation, Deduction, Other, Percent Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance, Percent Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance, Percent Effective Income Tax Rate Reconciliation, Nondeductible Expense, Restructuring Charges, Percent Effective Income Tax Rate Reconciliation, Nondeductible Expense, Restructuring Charges, Percent Effective Income Tax Rate Reconciliation, Other Adjustments, Percent Effective Income Tax Rate Reconciliation, Other Adjustments, Percent Effective Income Tax Rate Reconciliation, Percent Effective Income Tax Rate Reconciliation, Percent Schedule of Compensation Cost for Share-based Payment Arrangements, Allocation of Share-based Compensation Costs by Plan [Table Text Block] Schedule of Compensation Cost for Share-based Payment Arrangements, Allocation of Share-based Compensation Costs by Plan [Table Text Block] Nonvested Restricted Stock Shares Activity [Table Text Block] Nonvested Restricted Stock Shares Activity [Table Text Block] Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block] Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block] Schedule of Share-based Compensation, Stock Options, Activity [Table Text Block] Schedule of Share-based Compensation, Stock Options, Activity [Table Text Block] Schedule of Share-based Compensation, Shares Authorized under Stock Option Plans, by Exercise Price Range [Table Text Block] Schedule of Share-based Compensation, Shares Authorized under Stock Option Plans, by Exercise Price Range [Table Text Block] Chapter 11 Filing [Abstract] Chapter 11 Filing [Abstract] Total Stock, Shares Authorized Total Stock, Shares Authorized Total Stock, Shares Authorized Debt Instrument, Interest Rate, Stated Percentage Convertible senior notes Long-term Debt, Current Maturities Convertible Noteholders, Percent of New Common Stock Convertible Noteholders, Percent of New Common Stock Convertible Noteholders, Percent of New Common Stock Interest Paid Interest Paid Convertible Noteholders, New Notes Convertible Noteholders, New Notes Convertible Noteholders, New Notes Preferred Stock, Dividend Rate, Percentage Preferred Stock, Dividend Rate, Percentage Preferred Stock, Shares Outstanding Preferred Stock, Shares Outstanding Convertible preferred stock (Predecessor), 85,900 shares issued Other Long-term Debt, Current Class of Warrant or Right, Outstanding Class of Warrant or Right, Outstanding Preferred Investors, Each, Percent of New Common Stock Preferred Investors, Each, Percent of New Common Stock Preferred Investors, Each, Percent of New Common Stock Preferred Investors, Aggregate, Percent of New Common Stock Preferred Investors, Aggregate, Percent of New Common Stock Preferred Investors, Aggregate, Percent of New Common Stock Preferred Investors, Each, New Notes Preferred Investors, Each, New Notes Preferred Investors, Each, New Notes Government Funding Condition for Preferred Investor Investment Government Funding Condition for Preferred Investor Investment Government Funding Condition for the ACP for Further Preferred Investor Investment Preferred Investors, Aggregate, New Notes Preferred Investors, Aggregate, New Notes Preferred Investors, Aggregate, New Notes Stockholders, Percent of New Common Stock Stockholders, Percent of New Common Stock Stockholders, Percent of New Common Stock Secured Intercompany Financing Secured Intercompany Financing Secured Intercompany Financing Funds for Payments under Reorganization Plan Funds for Payments under Reorganization Plan Funds for Payments under Reorganization Plan Funds for Working Capital under Reorganization Plan Funds for Working Capital under Reorganization Plan Funds for Working Capital under Reorganization Plan Debtor in Possession Financing Repayments Debtor in possession financing repayments Debtor in possession financing repayments Professional Fees Professional Fees Trade payables Accounts Payable, Other, Current Compensation and benefits payable CompensationAndBenefitsPayable Compensation and benefits payable Accrued lease turnover - current Accrued lease turnover - current Accrued lease turnover - current Accrued interest payable on debt Accrued severance payments Accrued severance payments Accrued severance payments Other accrued liabilities Other Accrued Liabilities, Current Accounts payable and accrued liabilities Accounts Payable and Accrued Liabilities, Current Defined Benefit Plan, Effect of One-Percentage Point Change in Assumed Health Care Cost Trend Rates [Abstract] Defined Benefit Plan, Effect of One Percentage Point Increase on Accumulated Postretirement Benefit Obligation Defined Benefit Plan, Effect of One Percentage Point Increase on Accumulated Postretirement Benefit Obligation Defined Benefit Plan, Effect of One Percentage Point Decrease on Accumulated Postretirement Benefit Obligation Defined Benefit Plan, Effect of One Percentage Point Decrease on Accumulated Postretirement Benefit Obligation Defined Benefit Plan, Effect of One Percentage Point Increase on Service and Interest Cost Components Defined Benefit Plan, Effect of One Percentage Point Increase on Service and Interest Cost Components Defined Benefit Plan, Effect of One Percentage Point Decrease on Service and Interest Cost Components Defined Benefit Plan, Effect of One Percentage Point Decrease on Service and Interest Cost Components Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested Options Forfeited, Number of Shares Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested Options Forfeited, Number of Shares Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested Options Forfeited, Weighted Average Grant Date Fair Value Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested Options Forfeited, Weighted Average Grant Date Fair Value Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Outstanding Options, Weighted Average Exercise Price Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Outstanding Options, Weighted Average Exercise Price Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Outstanding Options, Weighted Average Remaining Contractual Term Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Outstanding Options, Weighted Average Remaining Contractual Term Cash and Cash Equivalents, Policy [Policy Text Block] Cash and Cash Equivalents, Policy [Policy Text Block] Inventory, Policy [Policy Text Block] Inventory, Policy [Policy Text Block] Income Tax, Policy [Policy Text Block] Income Tax, Policy [Policy Text Block] Property, Plant and Equipment, Policy [Policy Text Block] Property, Plant and Equipment, Policy [Policy Text Block] Advanced Technology Costs, Policy [Policy Text Block] Research and Development Expense, Policy [Policy Text Block] Goodwill and Intangible Assets, Policy [Policy Text Block] Goodwill and Intangible Assets, Policy [Policy Text Block] Fair Value of Financial Instruments, Policy [Policy Text Block] Fair Value of Financial Instruments, Policy [Policy Text Block] Revenue Recognition, Policy [Policy Text Block] Revenue Recognition, Policy [Policy Text Block] Pension and Other Postretirement Plans, Policy [Policy Text Block] Pension and Other Postretirement Plans, Policy [Policy Text Block] Share-based Compensation, Policy [Policy Text Block] Share-based Compensation, Option and Incentive Plans Policy [Policy Text Block] Use of Estimates, Policy [Policy Text Block] Use of Estimates, Policy [Policy Text Block] New Accounting Pronouncements, Policy [Policy Text Block] New Accounting Pronouncements, Policy [Policy Text Block] Schedule of Financial Instruments Recorded at Fair Value Fair Value, Measurement Inputs, Disclosure [Text Block] Schedule of Fair Value of Debt Fair Value of Debt Table Text Block Fair Value of Debt Table Text Block Plan of Reorganization Acceptance Rate Plan of Reorganization Acceptance Rate Plan of Reorganization Acceptance Rate Reduction in amount of third party debt obligations Reduction in amount of third party debt obligations Reduction in amount of third party debt obligations Property, Plant and Equipment [Abstract] Schedule of Property, Plant and Equipment [Table] Property, Plant and Equipment [Table] Property, Plant and Equipment [Line Items] Property, Plant and Equipment [Line Items] Property, Plant and Equipment, Gross Property, Plant and Equipment, Gross Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment Property, Plant and Equipment, Net Property, Plant and Equipment, Net Schedule of Net Income Per Share Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Schedule of Securities Excluded from Net Income Per Share Schedule of Securities Excluded from Net Income Per Share [Table Text Block] [Table Text Block] for Schedule of Securities Excluded from Net Income Per Share [Table] Debt Debt Disclosure [Text Block] General Discussion of Pension and Other Postretirement Benefits [Abstract] Defined Benefit Plan, Benefit Obligation Defined Benefit Plan, Benefit Obligation Defined Benefit Plan, Actuarial Gain (Loss) Defined Benefit Plan, Actuarial Gain (Loss) Defined Benefit Plan, Service Cost Defined Benefit Plan, Service Cost Defined Benefit Plan, Interest Cost Defined Benefit Plan, Interest Cost Defined Benefit Plan, Benefits Paid Defined Benefit Plan, Benefits Paid Defined Benefit Plan, Lump Sum Benefits Paid Defined Benefit Plan, Lump Sum Benefits Paid Defined Benefit Plan, Lump Sum Benefits Paid Defined Benefit Plan, Gross Prescription Drug Subsidy Receipts Received Defined Benefit Plan, Gross Prescription Drug Subsidy Receipts Received Defined Benefit Plan, Plan Amendments Defined Benefit Plan, Plan Amendments Defined Benefit Plan, Curtailments Defined Benefit Plan, Curtailments Defined Benefit Plan, Special Termination Benefits Defined Benefit Plan, Special Termination Benefits Defined Benefit Plan, Actual Return on Plan Assets Defined Benefit Plan, Actual Return on Plan Assets Defined Benefit Plan, Contributions by Employer Defined Benefit Plan, Contributions by Employer Defined Benefit Plan, Funded Status of Plan Defined Benefit Plan, Funded Status of Plan Amounts Recognized In Current Liabilities Amounts Recognized In Current Liabilities Amounts Recognized In Current Liabilities Amounts Recognized In Noncurrent Liabilities Amounts Recognized In Noncurrent Liabilities Amounts Recognized In Noncurrent Liabilities Defined Benefit Plan, Amounts Recognized in Balance Sheet Defined Benefit Plan, Amounts Recognized in Balance Sheet Amounts Recognized In Accumulated Other Comprehensive Income Pre Tax Net Actuarial Loss Amounts Recognized In Accumulated Other Comprehensive Income Pre Tax Net Actuarial Loss Amounts Recognized In Accumulated Other Comprehensive Income Pre Tax Net Actuarial Loss Recognized In Accumulated Other Comprehensive Income Pre Tax Prior Service Cost Credit Recognized In Accumulated Other Comprehensive Income Pre Tax Prior Service Cost Credit Recognized In Accumulated Other Comprehensive Income Pre Tax Prior Service Cost Credit AmountsRecognizedInAccumulatedOtherComprehensiveIncomePreTax AmountsRecognizedInAccumulatedOtherComprehensiveIncomePreTax Amounts Recognized In Accumulated Other Comprehensive Income Pre Tax Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Rate of Compensation Increase Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Rate of Compensation Increase Commitments and Contingencies Disclosure [Abstract] Minimum [Member] Minimum [Member] FY16 budget request for centrifuge program FY16 budget request for centrifuge program FY16 budget request for centrifuge program ACTDO DOE Funding – Monthly ACTDO DOE Funding – Monthly ACTDO DOE Funding – Monthly Liability for decontamination and decommissioning Asset Retirement Obligation D&D financial assurance ARO financial assurance ARO financial assurance Accrued liabilities for stored wastes Accrued liabilities for stored wastes Accrued liabilities for stored wastes Accrued lease turnover - Portsmouth, current Accrued lease turnover - Portsmouth, current Accrued lease turnover - Portsmouth, current Operating Leases, Rent Expense Operating Leases, Rent Expense ACP Sales Royalty Rate ACP Sales Royalty Rate American Centrifuge Plant (ACP) Sales Royalty Rate ACP Sales Royalty ACP Sales Royalty American Centrifuge Plant (ACP) Sales Royalty Commitments and Contingencies Commitments and Contingencies Disclosure [Text Block] Inventory, Current [Table] Inventory, Current [Table] Inventory [Axis] Inventory [Axis] Inventory [Domain] Inventory [Domain] Inventory [Line Items] Inventory [Line Items] Separative work units inventory Separative work units inventory Carrying amount as of the balance sheet date of separative work unit ("SWU") inventory. SWU is held as the SWU component of low enriched uranium. A SWU is the standard measure of uranium enrichment using a standard formula derived from the physics of enrichment. SWU costs are based on production costs and purchase costs. SWU inventory is valued at the lower of cost or market. Uranium inventory Uranium Inventory Carrying amount as of the balance sheet date of uranium inventory. Uranium is held in the form of natural uranium and as the uranium component of low enriched uranium. Uranium inventory is valued at the lower of cost or market. Materials and supplies Other Inventory, Supplies, Gross Inventories Inventory, Net Separative work units owed to customers and suppliers Separative work units owed to customers and suppliers Separative work units owed to customers and suppliers Uranium owed to customers and suppliers Uranium owed to customers and suppliers Uranium owed to customers and suppliers Inventories owed to customers and suppliers Inventories owed to customers and suppliers Cost of SWU and uranium inventories owed related to the transfer of title from USEC to customer at fabricator whereby fabricator has elected to order less material from USEC than is required. Amounts owed are satisfied when fabricator orders future bulk deliveries. Separative work units net of liability Separative work units net of liability Separative work units inventory net of liability Uranium inventory net of liability Uranium inventory net of liability Uranium inventory net of liability Inventories, net Inventory net of Liability Inventory net of Liability Defined Benefit Plan, Amounts Recognized in Other Comprehensive Income (Loss) [Abstract] Defined Benefit Plan, Amounts Recognized in Other Comprehensive Income (Loss), Net Actuarial Gain (Loss), before Tax Defined Benefit Plan, Amounts Recognized in Other Comprehensive Income (Loss), Net Actuarial Gain (Loss), before Tax Defined Benefit Plan, Amounts Recognized in Other Comprehensive Income (Loss), Net Prior Service Cost (Credit), before Tax Defined Benefit Plan, Amounts Recognized in Other Comprehensive Income (Loss), Net Prior Service Cost (Credit), before Tax Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI, Pension and Other Postretirement Benefit Plans, for Net Gain (Loss), before Tax Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI, Pension and Other Postretirement Benefit Plans, for Net Gain (Loss), before Tax Other Comprehensive (Income) Loss, Amortization Adjustment from AOCI, Pension and Other Postretirement Benefit Plans, for Net Prior Service Cost (Credit), before Tax Other Comprehensive (Income) Loss, Amortization Adjustment from AOCI, Pension and Other Postretirement Benefit Plans, for Net Prior Service Cost (Credit), before Tax Other Comprehensive (Income) Loss, Pension and Other Postretirement Benefit Plans, Adjustment, before Tax Other Comprehensive (Income) Loss, Pension and Other Postretirement Benefit Plans, Adjustment, before Tax Total recognized in net periodic benefit costs (income) and other comprehensive income (loss), pre-tax Total recognized in net periodic benefit costs (income) and other comprehensive income (loss), pre-tax Total recognized in net periodic benefit costs (income) and other comprehensive income (loss), pre-tax Schedule of Defined Benefit Plans Disclosures [Table] Schedule of Defined Benefit Plans Disclosures [Table] Defined Benefit Plans Disclosures, Defined Benefit Plans [Axis] Defined Benefit Plans [Domain] Pension Plan, Defined Benefit [Member] Pension Plan C [Member] Pension Plan C [Member] Pension Plan C [Member] Approximate Number of Plan Participants Approximate Number of Plan Participants Approximate Number of Plan Participants Defined Benefit Plan, Accumulated Benefit Obligation Defined Benefit Plan, Accumulated Benefit Obligation Curtailment (gain) loss Defined Benefit Plan, Recognized Net Gain (Loss) Due to Curtailments Decrease in pension liability, curtailments Additional credited service charge Defined Benefit Plan, Recognized Net Gain (Loss) Due to Settlements Increase in pension liability, additional credit service Defined Benefit Plan, Other Changes Fresh-Start Adjustment, Increase (Decrease), Accumulated Other Comprehensive Income (Loss) Fresh-Start Adjustment, Increase (Decrease), Accumulated Other Comprehensive Income (Loss) Expected defined benefit plan contributions for next fiscal year for non-qualified plans Expected defined benefit plan contributions for next fiscal year for non-qualified plans Expected defined benefit plan contributions for next fiscal year for non-qualified plans Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Net Unamortized Gain (Loss) Arising During Period, before Tax Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Net Unamortized Gain (Loss) Arising During Period, before Tax Defined Contribution Plan, Cost Recognized Defined Contribution Plan, Cost Recognized Schedule of Changes in Projected Benefit Obligations [Table Text Block] Schedule of Changes in Projected Benefit Obligations [Table Text Block] Schedule of Net Benefit Costs Schedule of Net Benefit Costs [Table Text Block] Schedule of Defined Benefit Plan Amounts Recognized in Other Comprehensive Income (Loss) [Table Text Block] Schedule of Defined Benefit Plan Amounts Recognized in Other Comprehensive Income (Loss) [Table Text Block] Schedule of Assumptions Used [Table Text Block] Schedule of Assumptions Used [Table Text Block] Schedule of Health Care Cost Trend Rates [Table Text Block] Schedule of Health Care Cost Trend Rates [Table Text Block] Schedule of Effect of One-Percentage-Point Change in Assumed Health Care Cost Trend Rates [Table Text Block] Schedule of Effect of One-Percentage-Point Change in Assumed Health Care Cost Trend Rates [Table Text Block] Schedule of Allocation of Plan Assets [Table Text Block] Schedule of Allocation of Plan Assets [Table Text Block] Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Table Text Block] Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Table Text Block] Schedule of Expected Benefit Payments [Table Text Block] Schedule of Expected Benefit Payments [Table Text Block] Goodwill Goodwill Proceeds from sale of subsidiary Gain on sale of subsidiary Net assets and liabilities of subsidiary Net assets and liabilities of subsidiary Net assets and liabilities of subsidiary Transaction costs for sale of subsidiary Transaction costs for sale of subsidiary Transaction costs for sale of subsidiary Income Taxes Income Tax Disclosure [Text Block] Intangible Assets Disclosure [Abstract] Intangible Assets Disclosure [Abstract] Finite-Lived Intangible Assets, Amortization Expense, Next Twelve Months Finite-Lived Intangible Assets, Amortization Expense, Next Twelve Months Finite-Lived Intangible Assets, Amortization Expense, Year Two Finite-Lived Intangible Assets, Amortization Expense, Year Two Finite-Lived Intangible Assets, Amortization Expense, Year Three Finite-Lived Intangible Assets, Amortization Expense, Year Three Finite-Lived Intangible Assets, Amortization Expense, Year Four Finite-Lived Intangible Assets, Amortization Expense, Year Four Finite-Lived Intangible Assets, Amortization Expense, Year Five Finite-Lived Intangible Assets, Amortization Expense, Year Five Finite-Lived Intangible Assets, Amortization Expense, after Year Five Finite-Lived Intangible Assets, Amortization Expense, after Year Five Finite-Lived Intangible Assets, Net Finite-Lived Intangible Assets, Net Property, Plant and Equipment, Disposals Property, Plant and Equipment, Disposals Asset Retirement Charges Production Related Impairments or Charges Depreciation Depreciation Property, Plant and Equipment, Transfers and Changes Property, Plant and Equipment, Transfers and Changes Accumulated Depreciation, Depletion and Amortization, Sale or Disposal of Property, Plant and Equipment Accumulated Depreciation, Depletion and Amortization, Sale or Disposal of Property, Plant and Equipment Net gains on sales of assets and property Proceeds from Sale of Property, Plant, and Equipment Proceeds from Sale of Property, Plant, and Equipment Compensation and Retirement Disclosure [Abstract] Defined Benefit Plan, Expected Future Benefit Payments, Next Twelve Months Defined Benefit Plan, Expected Future Benefit Payments, Next Twelve Months Defined Benefit Plan, Expected Future Benefit Payments, Year Two Defined Benefit Plan, Expected Future Benefit Payments, Year Two Defined Benefit Plan, Expected Future Benefit Payments, Year Three Defined Benefit Plan, Expected Future Benefit Payments, Year Three Defined Benefit Plan, Expected Future Benefit Payments, Year Four Defined Benefit Plan, Expected Future Benefit Payments, Year Four Defined Benefit Plan, Expected Future Benefit Payments, Year Five Defined Benefit Plan, Expected Future Benefit Payments, Year Five Defined Benefit Plan, Expected Future Benefit Payments, Five Fiscal Years Thereafter Defined Benefit Plan, Expected Future Benefit Payments, Five Fiscal Years Thereafter Postretirement Health and Life Benefits Plans [Member] Service costs Interest costs Expected return on plan assets (gains) Defined Benefit Plan, Expected Return on Plan Assets Amortization of prior service costs Defined Benefit Plan, Amortization of Prior Service Cost (Credit) Amortization of actuarial (gains) losses, net Curtailment (gains) Net benefit costs Defined Benefit Plan, Net Periodic Benefit Cost Total Revenue Revenues Cost of sales Cost of Revenue Gross profit (loss) Gross Profit Advanced technology costs Research and Development Expense Selling, general and administrative Selling, General and Administrative Expense Amortization of intangible assets Amortization of Intangible Assets Special charges for workforce reductions and advisory costs Restructuring Charges Other (income) Operating (loss) Operating Income (Loss) Interest (income) Investment Income, Interest Reorganization items, net Provision (benefit) for income taxes Income Tax Expense (Benefit) Net (loss) from continuing operations per share – basic and diluted Income (Loss) from Continuing Operations, Per Basic and Diluted Share Net (loss) per share – basic and diluted Earnings Per Share, Basic and Diluted Schedule of Restructuring and Related Costs [Table] Schedule of Restructuring and Related Costs [Table] Cash Payable [Member] Cash Payable [Member] Cash Payable [Member] Noncash [Member] Noncash [Member] Noncash [Member] Severance [Member] Severance [Member] Severance [Member] Advisory Costs [Member] Advisory Costs [Member] Advisory Costs [Member] Restructuring Type [Axis] Restructuring Type [Axis] Type of Restructuring [Domain] Type of Restructuring [Domain] Products and Services [Axis] Products and Services [Axis] Products and Services [Domain] Products and Services [Domain] Restructuring Cost and Reserve [Line Items] Restructuring Cost and Reserve [Line Items] Inventory Valuation Adjustments Inventory Write-down Non-production expenses Other Cost of Operating Revenue Site expenses Cost of Other Property Operating Expense Power Contract Losses Gain (Loss) on Sale of Commodity Contracts Accelerated property, plant and equipment expenses Accelerated propery, plant and equipment expenses Accelerated propery, plant and equipment expenses One-time termination benefit costs Severance Costs Payments for one-time termination benefits Payments for Restructuring Restructuring Liability Balance Restructuring Liability Balance Restructuring Liability Balance DOE Share of Paducah Termination Benefit Costs DOE Share of Paducah Termination Benefit Costs DOE Share of Paducah Termination Benefit Costs Structuring advisory costs Other Restructuring Costs Accounts Receivable, Net, Current Statement of Comprehensive Income [Abstract] Prior service credit arising during the period Other Comprehensive (Income) Loss, Pension and Other Postretirement Benefit Plans, Net Prior Service Cost (Credit) Arising During Period, before Tax Curtailment (gain) recognized in net income Amortization of actuarial (gains) losses, net Amortization of prior service costs (credits) Gain arising during the period Other comprehensive income (loss), before tax Other Comprehensive Income (Loss), before Tax Income tax expense related to items of other comprehensive income Other Comprehensive Income (Loss), Tax Other comprehensive income (loss), net of tax Other Comprehensive Income (Loss), Net of Tax Elimination of Predecessor Company accumulated other comprehensive loss Elimination of Predecessor Company accumulated other comprehensive loss Elimination of Predecessor Company accumulated other comprehensive loss Comprehensive income (loss) Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest Document and Entity Information Document and Entity Information Entity Registrant Name Entity Registrant Name Entity Central Index Key Entity Central Index Key Current Fiscal Year End Date Current Fiscal Year End Date Document Type Document Type Amendment Flag Amendment Flag Document Period End Date Document Period End Date Entity Filer Category Entity Filer Category Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Document Fiscal Year Focus Document Fiscal Year Focus Document Fiscal Period Focus Document Fiscal Period Focus Entity Well-known Seasoned Issuer Entity Well-known Seasoned Issuer Entity Public Float Entity Public Float Entity Current Reporting Status Entity Current Reporting Status Entity Voluntary Filers Entity Voluntary Filers Segment Reporting [Abstract] Revenue from top 10 customers Revenue from top 10 customers Revenue from top 10 customers Revenue from top 3 customers Revenue from top 3 customers Revenue from top 3 customers Revenue from first customer over 10 percent Revenue from first customer over 10 percent Revenue from first customer over 10 percent Revenue from second customer over 10 percent Revenue from second customer over 10 percent Revenue from second customer over 10 percent Revenue from third customer over 10 percent Revenue from third customer over 10 percent Revenue from third customer over 10 percent Revenue from fourth customer over 10 percent Revenue from fourth customer over 10 percent Revenue from fourth customer over 10 percent Segment Reporting Information, Revenue for Reportable Segment [Abstract] Revenues [Abstract] Revenues [Abstract] Separative work units Separative work units Revenue derived from sales of the separative work unit (SWU) component of low enriched uranium (LEU). Uranium Uranium Revenue derived from sales of uranium and the uranium component of low enriched uranium (LEU). Revenue from low enriched uranium segment Revenue from low enriched uranium segment Revenue from low enriched uranium segment Contract services Contracts Revenue LEU segment gross profit Gross Profit From Low Enriched Uranium Segment Gross Profit From Low Enriched Uranium Segment Contract services segment gross profit Contracts Gross Profit Contracts Gross Profit Gross profit Gross profits all segments Gross profits all segments LEU Segment Assets LEU Segment Assets LEU Segment Assets Contract Services Segment Assets Contract Services Segment Assets Contract Services Segment Assets Total Assets Assets Geographic Areas, Revenues from External Customers [Abstract] Schedule of Revenues from External Customers and Long-Lived Assets [Table] Schedule of Revenues from External Customers and Long-Lived Assets [Table] Consolidation Items [Axis] Consolidation Items [Axis] Consolidation Items [Domain] Consolidation Items [Domain] Geographical [Axis] Geographical [Axis] Geographical [Domain] Geographical [Domain] Revenues from External Customers and Long-Lived Assets [Line Items] Revenues from External Customers and Long-Lived Assets [Line Items] Revenue United States Revenue United States Revenue United States Revenue Japan Revenue Japan Revenue Japan Revenue Other Countries Revenue Other Countries Revenue Other Countries Revenue Foreign Revenue Foreign Revenue Foreign Stockholders' Equity Note Disclosure [Text Block] Stockholders' Equity Note Disclosure [Text Block] Major Types of Debt and Equity Securities [Axis] Major Types of Debt and Equity Securities [Axis] Major Types of Debt and Equity Securities [Domain] Major Types of Debt and Equity Securities [Domain] Equity Securities [Member] Equity Securities [Member] Debt Securities [Member] Debt Securities [Member] Defined Benefit Plan, Actual Plan Asset Allocations Defined Benefit Plan, Actual Plan Asset Allocations Defined Benefit Plan, Target Plan Asset Allocations Range Minimum Defined Benefit Plan, Target Plan Asset Allocations Range Minimum Defined Benefit Plan, Target Plan Asset Allocations Range Maximum Defined Benefit Plan, Target Plan Asset Allocations Range Maximum Income Statement [Abstract] Revenue: Total revenue Cost of Sales: Cost of Revenue [Abstract] Separative work units and uranium Cost of Goods Sold Contract services Contract Revenue Cost Total cost of sales Gross profit (loss) Special charges for workforce reductions and advisory costs Operating (loss) Income (loss) from continuing operations before income taxes Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Extraordinary Items, Noncontrolling Interest Income (loss) from continuing operations Net income (loss) Weighted-average number of shares outstanding: Weighted Average Number of Shares Outstanding, Diluted [Abstract] Weighted average number of shares outstanding - basic Weighted average number of shares outstanding - diluted Schedule of Accounts Receivable Schedule of Accounts, Notes, Loans and Financing Receivable [Table Text Block] Reorganization under Chapter 11 of US Bankruptcy Code Disclosure Reorganization under Chapter 11 of US Bankruptcy Code Disclosure [Text Block] Property, Plant and Equipment Disclosure Property, Plant and Equipment Disclosure [Text Block] Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract] Other comprehensive income, net of tax Intangible Assets Disclosure [Text Block] Goodwill and Intangible Assets Disclosure [Text Block] Property, Plant and Equipment Property, Plant and Equipment [Table Text Block] Property, Plant and Equipment, Sales Property, Plant and Equipment, Schedule of Significant Acquisitions and Disposals [Table Text Block] Accounts Receivable Loans, Notes, Trade and Other Receivables Disclosure [Text Block] Finite-Lived Intangible Assets by Major Class [Axis] Finite-Lived Intangible Assets by Major Class [Axis] Finite-Lived Intangible Assets, Major Class Name [Domain] Finite-Lived Intangible Assets, Major Class Name [Domain] Contract-Based Intangible Assets [Member] Contract-Based Intangible Assets [Member] Payments of Financing Costs Enterprise Value Enterprise Value Enterprise Value Long-term debt Common Stock, Value, Outstanding Common Stock, Value, Outstanding Common Stock, Shares, Outstanding Common Stock, Shares, Outstanding Shares Issued, Price Per Share Shares Issued, Price Per Share Other Liabilities, Fair Value Disclosure Other Liabilities, Fair Value Disclosure Reorganization Value Reorganization Value Payments for Fees Payments for Fees Payment of Claims Payment Of Claims Payment Of Claims Payment of Reorganization Adjustments Payment of Reorganization Adjustments Payment of Reorganization Adjustments Liabilities Subject to Compromise, 3% Convertible Senior Notes and Accrued Interest Liabilities Subject to Compromise, Debt and Accrued Interest Liabilities Subject to Compromise, Convertible Preferred Stock and Paid-in-Kind Dividends Payable Liabilities Subject to Compromise, Other Liabilities Liabilities Subject to Compromise, Accounts Payable and Accrued Liabilities Liabilities Subject to Compromise, Accounts Payable and Accrued Liabilities Liabilities subject to compromise Liabilities Subject to Compromise Fresh-Start Adjustment, Increase (Decrease), Inventories Fresh-Start Adjustment, Increase (Decrease), Inventories Fresh-Start Adjustment, Increase (Decrease), Other Deferred Costs Fresh-Start Adjustment, Increase (Decrease), Other Deferred Costs Fresh-Start Adjustment, Increase (Decrease), Other Deferred Costs Fresh-Start Adjustment, Increase (Decrease), Other Current Liabilities Fresh-Start Adjustment, Increase (Decrease), Other Current Liabilities Revaluation of deferred revenue, net of deferred costs Fresh-Start Adjustment, Increase (Decrease), Amortizable Intangible Assets Fresh-Start Adjustment, Increase (Decrease), Amortizable Intangible Assets Intangible assets Intangible Assets, Net (Excluding Goodwill) Income Tax Authority [Axis] Income Tax Authority [Axis] Income Tax Authority [Domain] Income Tax Authority [Domain] Domestic Tax Authority [Member] Domestic Tax Authority [Member] State and Local Jurisdiction [Member] State and Local Jurisdiction [Member] Foreign Tax Authority [Member] Foreign Tax Authority [Member] Current Income Tax Expense (Benefit) Current Income Tax Expense (Benefit) Deferred income taxes Deferred Income Tax Expense (Benefit) Schedule of Intangible Assets and Excess Reorganization Value [Table Text Block] Schedule of Intangible Assets and Excess Reorganization Value [Table Text Block] Schedule of Intangible Assets and Excess Reorganization Value [Table Text Block] Schedule of Finite-Lived Intangible Assets, Future Amortization Expense [Table Text Block] Schedule of Finite-Lived Intangible Assets, Future Amortization Expense [Table Text Block] Options excluded from diluted net income per share Options with exercise price greater than market price Options with exercise price greater than market price Warrants excluded from diluted net income per share Warrants with exercise price greater than market price Warrants with exercise price greater than market price Exercise price of excluded options Investment Options, Exercise Price Exercise price of excluded warrants Investment Warrants, Exercise Price Fresh-Start Adjustments [Table] Fresh-Start Adjustments [Table] Pre Eliminations [Member] Pre Eliminations [Member] Pre Eliminations [Member] Fresh-Start Adjustments [Axis] Fresh-Start Adjustments [Axis] Type of Fresh-Start Adjustment [Domain] Type of Fresh-Start Adjustment [Domain] Reorganization Adjustments [Member] Reorganization Adjustments [Member] Reorganization Adjustments [Member] Fresh Start Adjustments [Member] Fresh Start Adjustments [Member] Fresh Start Adjustments [Member] Fresh-Start Adjustment [Line Items] Fresh-Start Adjustment [Line Items] ASSETS Assets [Abstract] Current Assets Assets, Current [Abstract] Cash and cash equivalents Accounts receivable, net Inventories Deferred costs associated with deferred revenue Other Deferred Costs, Net Other current assets Prepaid Expense and Other Assets, Current Total current assets Assets, Current Property, plant and equipment, net Deferred income taxes Deferred Tax Assets, Net, Noncurrent Deposits for surety bonds Deposits Assets, Noncurrent Excess reorganization value Other long-term assets Other Assets, Noncurrent LIABILITIES AND STOCKHOLDERS’ EQUITY (DEFICIT) Liabilities and Equity [Abstract] Current Liabilities Liabilities, Current [Abstract] Accounts payable and accrued liabilities Payables under SWU purchase agreements Accounts Payable, Current Deferred taxes Deferred Tax Liabilities, Net, Current Inventories owed to customers and suppliers Deferred revenue Deferred Revenue and Credits, Current Convertible senior notes (Predecessor) Short-term Bank Loans and Notes Payable Total current liabilities Liabilities, Current Postretirement health and life benefit obligations Other Postretirement Defined Benefit Plan, Liabilities, Noncurrent Pension benefit liabilities Defined Benefit Pension Plan, Liabilities, Noncurrent Total liabilities not subject to compromise Total liabilities not subject to compromise Total liabilities not subject to compromise Total liabilities Liabilities, Noncurrent Commitments and contingencies (Note 19) Commitments and Contingencies Common stock Common Stock, Value, Issued Excess of capital over par value Additional Paid in Capital Retained earnings (deficit) Retained Earnings (Accumulated Deficit) Treasury stock Treasury Stock, Value Accumulated other comprehensive income (loss), net of tax Accumulated Other Comprehensive Income (Loss), Net of Tax Total stockholders’ equity (deficit) Total Liabilities and Stockholders’ Equity (Deficit) Liabilities and Equity Adjustment, Assets Fresh-Start Adjustment, Increase (Decrease), Assets [Abstract] Cash and Cash Equivalents Fresh-Start Adjustment, Increase (Decrease), Cash and Cash Equivalents Inventories Deferred costs associated with deferred revenue Other current assets Fresh-Start Adjustment, Increase (Decrease), Prepaid and Other Current Assets Total current assets Fresh-Start Adjustment, Increase (Decrease), Current Assets Deferred taxes Fresh-Start Adjustment, Increase (Decrease), Deferred Income Tax Assets, Noncurrent Intangible assets Excess reorganization value Fresh-Start Adjustment, Increase (Decrease), Goodwill Other long-term assets Fresh-Start Adjustment, Increase (Decrease), Other Assets, Noncurrent Total Assets Fresh-Start Adjustment, Increase (Decrease), Assets Adjustment, Liabilities and Stockholders' Equity (Deficit) Fresh-Start Adjustment, Increase (Decrease), Liabilities and Stockholders' Equity [Abstract] Accounts payable and accrued liabilities Fresh-Start Adjustment, Increase (Decrease), Accrued Liabilities Deferred taxes Fresh-Start Adjustment, Increase (Decrease), Deferred Income Tax Liabilities, Current Deferred revenue Long-term debt Fresh-Start Adjustment, Increase (Decrease), Other Long-term Debt Postretirement health and life benefit obligations Fresh-Start Adjustment, Increase (Decrease), Other Postretirement Obligations Pension benefit liabilities Fresh-Start Adjustment, Increase (Decrease), Pension Obligations Liabilities Subject to Compromise, Debt and Accrued Interest Liabilities Subject to Compromise, Other Liabilities Liabilities Subject to Compromise Total liabilities Fresh-Start Adjustment, Increase (Decrease), Liabilities Common stock Fresh-Start Adjustment, Increase (Decrease), Common Stock Excess of capital over par value Fresh-Start Adjustment, Increase (Decrease), Additional Paid-in Capital Treasury stock Fresh-Start Adjustment, Increase (Decrease), Preferred and Common Stock Held in Treasury Accumulated other comprehensive loss, net of tax Retained earnings (deficit) Fresh-Start Adjustment, Increase (Decrease), Retained Earnings (Deficit) Total stockholders' equity (deficit) Fresh-Start Adjustment, Increase (Decrease), Stockholders' Equity Total Liabilties and Stockholders' Equity (Deficit) Fresh-Start Adjustment, Increase (Decrease), Liabilities and Stockholders' Equity Segment Information Segment Reporting Disclosure [Text Block] Accumulated Other Comprehensive Income (Loss) Comprehensive Income (Loss) Note [Text Block] Reorganization Items, Net [Table Text Block] Reorganization Items, Net [Table Text Block] Reorganization Items, Net [Table Text Block] Fresh Start Accounting [Text Block] Fresh Start Accounting [Text Block] Fresh Start Accounting [Text Block] Warrants with exercise price greater than market price Pension and Postretirement Health and Life Benefits Pension and Other Postretirement Benefits Disclosure [Text Block] Increase (decrease) in deferred tax asset valuation allowance Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount Deferred Tax Liabilities, Net, Current Deferred Tax Assets, Net, Noncurrent Operating Loss Carryforwards Operating Loss Carryforwards Annual limitation of NOL carryforwards and tax credits generated prior to ownership change Annual limitation of NOL carryforwards and tax credits generated prior to ownership change Annual limitation of net operating loss carryforwards and tax credits generated prior to ownership change (that are not reduced by attribute reduction) Benefit for tax basis written off related to asset retirements Benefit for tax basis written off related to asset retirements Benefit for additional tax basis written off related to asset retirements for depreciation previously allocated to exempt income under the extraterritorial income exclusion. Provision (benefit) for income taxes Other Comprehensive Income (Loss), Tax Discontinued Operation, Tax Effect of Discontinued Operation Discontinued Operation, Tax Effect of Discontinued Operation Unrecognized Tax Benefits, Income Tax Penalties Expense Reduction Unrecognized Tax Benefits, Income Tax Penalties Expense Income Tax Examination, Penalties and Interest Expense Reduction Income Tax Examination, Penalties and Interest Expense Income Tax Examination, Penalties and Interest Accrued Income Tax Examination, Penalties and Interest Accrued Special Charges Summary [Table Text Block] Restructuring and Related Costs [Table Text Block] Schedule of Revenue from External Customers Attributed to Foreign Countries by Geographic Area [Table Text Block] Schedule of Revenue from External Customers Attributed to Foreign Countries by Geographic Area [Table Text Block] Segment Reporting Information Schedule of Segment Reporting Information, by Segment [Table Text Block] Award Type [Axis] Award Type [Axis] Equity Award [Domain] Equity Award [Domain] Employee Stock Option [Member] Employee Stock Option [Member] Restricted Stock [Member] Restricted Stock [Member] Weighted-average period in years of costs to be recognized Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized Long-term debt, fair value Long-term Debt, Fair Value Convertible senior notes, fair value Convertible Debt, Fair Value Disclosures Accounts Payable and Accrued Liabilities [Text Block] Accounts Payable and Accrued Liabilities Disclosure [Text Block] Inventories provided by customers and suppliers Inventories Provided by Customers and Suppliers 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 Decline in Uranium Quantities Provided by Customers and Suppliers Decline in Uranium Quantities Provided by Customers and Suppliers Decline in Uranium Quantities Provided by Customers and Suppliers Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract] Operating Leases, Future Minimum Payments Due, Next Twelve Months Operating Leases, Future Minimum Payments Due, Next Twelve Months Operating Leases, Future Minimum Payments, Due in Two Years Operating Leases, Future Minimum Payments, Due in Two Years Operating Leases, Future Minimum Payments, Due in Three Years Operating Leases, Future Minimum Payments, Due in Three Years Operating Leases, Future Minimum Payments, Due in Four Years Operating Leases, Future Minimum Payments, Due in Four Years Operating Leases, Future Minimum Payments, Due in Five Years Operating Leases, Future Minimum Payments, Due in Five Years Operating Leases, Future Minimum Payments, Due Thereafter Operating Leases, Future Minimum Payments, Due Thereafter Operating Leases, Future Minimum Payments Due Operating Leases, Future Minimum Payments Due Fair Value Measurements Fair Value Disclosures [Text Block] Statement of Financial Position [Abstract] Total current assets Total Assets Total current liabilities Total liabilities Total stockholders’ equity (deficit) Total Liabilities and Stockholders’ Equity (Deficit) Operating Activities [Axis] Operating Activities [Axis] Operating Activities [Domain] Operating Activities [Domain] Segment, Discontinued Operations [Member] Discontinued Operations [Member] Contract services costs Gross profit Operating income Income before income taxes Discontinued Operation, Income (Loss) from Discontinued Operation, before Income Tax Provision for income taxes Net income from discontinued operations Income (Loss) from Discontinued Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest Goodwill and Intangible Assets Disclosure [Abstract] Schedule of Finite-Lived Intangible Assets [Table] Schedule of Finite-Lived Intangible Assets [Table] Customer-Related Intangible Assets [Member] Customer-Related Intangible Assets [Member] Finite-Lived Intangible Assets [Line Items] Finite-Lived Intangible Assets [Line Items] Accumulated amortization Finite-Lived Intangible Assets, Accumulated Amortization Average useful life of finite-lived intangible assets Finite-Lived Intangible Asset, Useful Life Schedule of Future Minimum Rental Payments for Operating Leases [Table Text Block] Schedule of Future Minimum Rental Payments for Operating Leases [Table Text Block] Schedule of Inventories Schedule of Inventory, Current [Table Text Block]