Centrus Energy (LEU) 10-K 9 Feb 24 2023 FY Annual report Financial data

Cover Page

Cover Page - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2023	Feb. 01, 2024	Jun. 30, 2023
Document Annual Report	true
Document Transition Report	false
Document Period End Date	Dec. 31, 2023
Document Fiscal Year Focus	2023
Document Fiscal Period Focus	FY
Entity File Number	1-14287
Entity Registrant Name	Centrus Energy Corp.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	52-2107911
Entity Address, Address Line One	6901 Rockledge Drive, Suite 800
Entity Address, City or Town	Bethesda
Entity Address, State or Province	MD
Entity Address, Postal Zip Code	20817
City Area Code	(301)
Local Phone Number	564-3200
Title of 12(b) Security	Class A Common Stock, par value $0.10 per share
Trading Symbol	LEU
Security Exchange Name	NYSEAMER
Entity Interactive Data Current	Yes
Entity Filer Category	Accelerated Filer
Entity Central Index Key	0001065059
Current Fiscal Year End Date	--12-31
Amendment Flag	false
Entity Current Reporting Status	Yes
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Public Float			$ 411.7
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Document Type	10-K
ICFR Auditor Attestation Flag	true
Documents Incorporated by Reference	DOCUMENTS INCORPORATED BY REFERENCE Portions of the definitive proxy statement for the 2024 annual meeting of shareholders to be filed with the Securities and Exchange Commission within 120 days after the end of fiscal year 2023 are incorporated by reference into Part III of this Annual Report on Form 10-K.
Document Financial Statement Error Correction [Flag]	false
Common Class A [Member]
Common Stock, Par or Stated Value Per Share	$ 0.10
Entity Common Stock, Shares Outstanding		14,956,434
Common Class B [Member]
Common Stock, Par or Stated Value Per Share	$ 0.10
Entity Common Stock, Shares Outstanding		719,200

Audit Information

Audit Information	12 Months Ended
	Dec. 31, 2023
Audit Information [Abstract]
Auditor Name	DELOITTE & TOUCHE LLP
Auditor Firm ID	34
Auditor Location	McLean, Virginia

CONSOLIDATED BALANCE SHEETS

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Current Assets
Cash and cash equivalents	$ 201.2	$ 179.9
Accounts receivable, net	49.4	38.1
Inventories	306.4	209.2
Deferred costs associated with deferred revenue	117.6	135.7
Other current assets	10.8	24.2
Total current assets	685.4	587.1
Property, Plant and Equipment, Net	7	5.5
Deposits for surety bonds	32.4	32.3
Intangible assets	39.4	45.7
Deferred tax assets, net	28.5	26.8
Other long-term assets	3.5	8.1
Total Assets	796.2	705.5
Current Liabilities
Accounts payable and accrued liabilities	56.2	65.5
Payables under SWU purchase agreements	41.9	43.6
Inventories owed to customers and suppliers	84.3	60.8
Deferred revenue and advances from customers	282.6	273.2
Current debt	6.1	6.1
Total current liabilities	471.1	449.2
Long-term debt	89.6	95.7
Postretirement health and life benefit obligations	81.2	84.5
Pension benefit liabilities	17.3	43.6
Advances from customers	32.8	46.2
Long-term SWU Loans	63.1	48.7
Other long-term liabilities	8.8	11.7
Total liabilities	$ 763.9	779.6
Stockholders' Deficit
Common Stock, Shares, Issued	15,675,634
Excess of capital over par value	$ 180.5	158.1
Accumulated deficit	(149.5)	(233.9)
Accumulated other comprehensive income (loss), net of tax	(0.3)	0.2
Total stockholders' deficit	32.3	(74.1)
Total Liabilities and Stockholders’ Equity (Deficit)	796.2	705.5
Preferred Series A [Member]
Stockholders' Deficit
Preferred stock	0	0
Preferred Series B [Member]
Stockholders' Deficit
Preferred stock	$ 0	$ 0
Common Class A [Member]
Stockholders' Deficit
Common Stock, Shares Authorized	70,000,000
Common Stock, Par or Stated Value Per Share	$ 0.10
Common Stock, Shares, Issued	14,956,434	13,919,646
Common stock	$ 1.5	$ 1.4
Common Class B [Member]
Stockholders' Deficit
Common Stock, Shares Authorized	30,000,000
Common Stock, Par or Stated Value Per Share	$ 0.10
Common Stock, Shares, Issued	719,200
Common stock	$ 0.1	$ 0.1
Series B Preferred Stock [Member]
Current Liabilities
Preferred Stock, Par Value Per Share	$ 1

CONSOLIDATED BALANCE SHEETS (Pa

CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2017
Preferred Stock, Shares Authorized	20,000,000
Preferred Stock, Shares Issued			104,574
Common Stock, Shares, Issued	15,675,634
Series B Preferred Stock [Member]
Preferred Stock, Par Value Per Share	$ 1
Common Class A [Member]
Common Stock, Par or Stated Value Per Share	$ 0.10
Common Stock, Shares Authorized	70,000,000
Common Stock, Shares, Issued	14,956,434	13,919,646
Common Class B [Member]
Common Stock, Par or Stated Value Per Share	$ 0.10
Common Stock, Shares Authorized	30,000,000
Common Stock, Shares, Issued	719,200

CONSOLIDATED STATEMENTS OF OPER

CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Total revenue	$ 320.2	$ 293.8	$ 298.3
Cost of sales	208.1	175.9	183.8
Gross profit (loss)	112.1	117.9	114.5
Advanced technology license and decommissioning costs	14.2	14.8	2.1
Selling, general and administrative	35.6	33.9	36
Amortization of intangible assets	6.3	9	8.1
Special charges for workforce reductions and advisory costs	3.6	0.5	0
Operating income (loss)	52.4	59.7	68.3
Nonoperating components of net periodic benefit expense (income)	(23.2)	(6.6)	(67.6)
Interest expense	1.3	0.5	0.1
Investment income	(8.7)	(2)	(0.1)
Other Nonoperating Income	(1.5)	0	0
Income (loss) before income taxes	84.5	67.8	135.9
Provision (benefit) for income taxes	0.1	15.6	(39.1)
Net income (loss)	84.4	52.2	175
Distributed earnings allocable to warrant modification	0	1.5	0
Preferred stock dividends, undeclared and cumulative	0	0	2.1
Distributed earnings allocable to retired preferred shares	0		37.6
Net income (loss) allocable to common stockholders	$ 84.4	$ 50.7	$ 135.3
Net income (loss) per common share - basic	$ 5.55	$ 3.47	$ 10.03
Net income (loss) per common share - diluted	$ 5.44	$ 3.38	$ 9.75
Weighted-average number of shares outstanding:
Average number of shares outstanding, basic	15,212	14,601	13,493
Average number of shares outstanding, diluted	15,501	14,988	13,879
Accumulated Deficit [Member]
Net income (loss)	$ 84.4	$ 52.2	$ 175
Distributed earnings allocable to warrant modification	0	1.5	0
Product [Member]
Total revenue	269	235.6	186.1
Cost of sales	163.9	105	113.1
Separative Work Units [Member]
Total revenue	208.2	196.2	163.3
Uranium [Member]
Total revenue	60.8	39.4	22.8
Service [Member]
Cost of sales	$ 44.2	$ 70.9	$ 70.7

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Cash Flows from Operating Activities
Net income	$ 84.4	$ 52.2	$ 175
Adjustments to reconcile net income (loss) to net cash (used in) operating activities:
Depreciation and amortization	7.1	9.6	8.6
Accrued loss on long-term contract	(20)	19.5	(7.2)
Increase (Decrease) in Deferred Income Taxes	1.6	(14.7)	39.5
Retirement benefit plans (gains) losses, net	(24.6)	7.8	(50.5)
Revaluation of inventory borrowing	7.4	8	4.8
Equity Related Compensation	2.3	1.9	12.1
Other Operating Activities, Cash Flow Statement	(1.6)	0	0
Changes in operating assets and liabilities:
Accounts receivable – (increase) decrease	(11.3)	(9)	0.5
Increase (Decrease) in Inventories	(83.8)	(88.5)	(14.2)
Increase Decrease in Inventories Owed to Suppliers	23.5	52.4	3.5
Increase (Decrease) in Other Current Assets	14.9	(15.6)	(1)
Payables under SWU purchase agreements – increase (decrease)	(1.7)	5.7	16.6
Deferred revenue, net of deferred costs – increase (decrease)	12.1	(22.5)	13.2
Accounts payable and other liabilities – increase (decrease)	8.5	2.6	(4.6)
Pension and postretirement liabilities - increase (decrease)	(5.7)	(18.1)	(67)
Other, net	(0.8)	(0.1)	(0.3)
Net cash used in operating activities	9.1	20.6	50
Cash Flows Provided by Investing Activities
Capital expenditures	(1.6)	(0.7)	(1.2)
Net Cash Provided by (Used in) Investing Activities	(1.6)	(0.7)	(1.2)
Cash Flows Used in Financing Activities
Proceeds from the sale of common stock, net	(23.2)	(3.6)	(42.1)
Redemption of preferred stock, net	0	0	(44.4)
Repayments of Debt	(6.1)	(6.1)	(6.1)
Exercise of stock options	0	0.4	0.9
Shares withheld for employee taxes	(3)	(1.9)	(2.4)
Proceeds from (Payments for) Other Financing Activities	(0.2)	(0.3)	0
Net cash used in financing activities	13.9	(4.3)	(9.9)
Decrease in cash, cash equivalents and restricted cash	21.4	15.6	38.9
Cash, cash equivalents and restricted cash, start of period	212.4	196.8	157.9
Cash, cash equivalents and restricted cash, end of period	233.8	212.4	196.8
Property, plant and equipment included in accounts payable and accrued liabilities
Supplemental Cash Flow Information:
Other Significant Noncash Transaction, Value of Consideration Given	0.9	0.2	0
Other Significant Noncash Transaction, Value of Consideration Given	(0.9)	(0.2)	0
Equity issuance costs included in accounts payable and accrued liabilities [Member]
Supplemental Cash Flow Information:
Other Significant Noncash Transaction, Value of Consideration Given	0	0.2	0.4
Other Significant Noncash Transaction, Value of Consideration Given	0	(0.2)	(0.4)
Disposal of right to use lease assets [Member]
Supplemental Cash Flow Information:
Other Significant Noncash Transaction, Value of Consideration Given	0	0	1
Other Significant Noncash Transaction, Value of Consideration Given	0	0	(1)
Reclassification of equity compensation liability to equity [Member]
Supplemental Cash Flow Information:
Other Significant Noncash Transaction, Value of Consideration Given	0	10.6	7.5
Other Significant Noncash Transaction, Value of Consideration Given	0	(10.6)	(7.5)
Common stock and warrant issued in exchange for preferred stock [Member]
Supplemental Cash Flow Information:
Other Significant Noncash Transaction, Value of Consideration Given	0	0	7.5
Other Significant Noncash Transaction, Value of Consideration Given	0	0	(7.5)
Adjustment to Right of Use Lease due to Modification [Domain]
Supplemental Cash Flow Information:
Other Significant Noncash Transaction, Value of Consideration Given	(4.2)	6.6	0
Other Significant Noncash Transaction, Value of Consideration Given	4.2	(6.6)	0
Distributed Earnings Allocable to Warrant Modification [Domain]
Supplemental Cash Flow Information:
Other Significant Noncash Transaction, Value of Consideration Given	0	1.5	0
Other Significant Noncash Transaction, Value of Consideration Given	$ 0	$ (1.5)	$ 0

CONSOLIDATED STATEMENTS OF STOC

CONSOLIDATED STATEMENTS OF STOCKHOLDERS' DEFICIT - USD ($) $ in Millions	Total	Preferred Stock [Member]	Common Stock [Member] Common Class A [Member]	Common Stock [Member] Common Class B [Member]	Excess of Capital over Par Value [Member]	Accumulated Deficit [Member]	Accumulated Other Comprehensive Income (Loss) [Member]
Beginning Balance at Dec. 31, 2020	$ (320.6)	$ 0.1	$ 1.1	$ 0.1	$ 85	$ (407.7)	$ 0.8
Net income	175	0	0	0	0	175	0
Stock issued during period	42.1	0	0.2	0	41.9	0	0
Exchange of preferred stock for common stock and common stock warrant	0	0	0.1	0	7.5	(7.6)	0
Stock Repurchased and Retired During Period, Value	(44.4)	(0.1)	0	0	0	(44.3)	0
Reclassification of stock-based compensation from liability to equity	7.5	0	0	0	7.5	0	0
Shares withheld for employee taxes	(2.4)	0	0	0	2.4	0	0
Other comprehensive income, net of tax	(0.3)	0	0	0	0	0	(0.3)
Restricted and other common stock issued, net of amortization	1.2	0	0	0	1.2	0	0
Ending Balance at Dec. 31, 2021	(141.9)	0	1.4	0.1	140.7	(284.6)	0.5
Net income	52.2	0	0	0	0	52.2	0
Stock issued during period	4	0	0	0	4	0	0
Reclassification of stock-based compensation from liability to equity	10.6	0	0	0	10.6	0	0
Shares withheld for employee taxes	(1.9)	0	0	0	1.9	0	0
Adjustments to Additional Paid in Capital, Other	0	0	0	0	(1.5)	1.5	0
Other comprehensive income, net of tax	(0.3)	0	0	0	0	0	(0.3)
Restricted and other common stock issued, net of amortization	3.2	0	0	0	3.2	0	0
Ending Balance at Dec. 31, 2022	(74.1)	0	1.4	0.1	158.1	(233.9)	0.2
Net income	84.4	0	0	0	0	84.4	0
Stock issued during period	23.2	0	0.1	0	23.1	0	0
Shares withheld for employee taxes	(3)	0	0	0	3	0	0
Other comprehensive income, net of tax	(0.5)	0	0	0	0	0	(0.5)
Restricted and other common stock issued, net of amortization	2.3	0	0	0	2.3	0	0
Ending Balance at Dec. 31, 2023	$ 32.3	$ 0	$ 1.5	$ 0.1	$ 180.5	$ (149.5)	$ (0.3)

Cash, Cash Equivalents and Rest

Cash, Cash Equivalents and Restricted Cash	12 Months Ended
	Dec. 31, 2023
Cash, Cash Equivalents and Restricted Cash [Abstract]
Cash and Cash Equivalents Disclosure	CASH, CASH EQUIVALENTS AND RESTRICTED CASH The following table summarizes the Company’s cash, cash equivalents and restricted cash as presented on the Consolidated Balance Sheets to amounts on the Consolidated Statements of Cash Flows (in millions): December 31, 2023 2022 Cash and cash equivalents $ 201.2 $ 179.9 Deposits for financial assurance - current (a) 0.2 0.2 Deposits for financial assurance - non current 32.4 32.3 Total cash, cash equivalents and restricted cash $ 233.8 $ 212.4 (a) Deposits for financial assurance - current is included within Other Current Assets in the Consolidated Balance Sheets. The Company has $6.8 million and $0 million denominated in euros as of December 31, 2023 and 2022, respectively, and recorded less than $0.1 million in transaction losses in each of the years ended December 31, 2023, 2022, and 2021. The following table provides additional detail regarding the Company’s deposits for financial assurance (in millions): December 31, 2023 December 31, 2022 Current Long-Term Current Long-Term Collateral for Inventory Loans $ — $ 29.8 $ — $ 29.8 Workers Compensation — 2.5 — 2.4 Other 0.2 0.1 0.2 0.1 Total deposits for financial assurance $ 0.2 $ 32.4 $ 0.2 $ 32.3 The Company has provided financial assurance to states in which it was previously self-insured for workers’ compensation in accordance with each state’s requirements in the form of a surety bond or deposit that is fully cash collateralized by Centrus. Each surety bond or deposit is subject to reduction and/or cancellation, as each state determines that the likelihood of further workers’ compensation obligations related to the period of self-insurance. In March, May, and October 2022, the Company entered into three inventory loans which required a cash deposit into an escrow fund. Refer to Note 4 , Inventories.

Property, Plant and Equipment

Property, Plant and Equipment	12 Months Ended
	Dec. 31, 2023
Property, Plant and Equipment [Abstract]
Property, Plant and Equipment	PROPERTY, PLANT AND EQUIPMENT, NET A summary of changes in property, plant and equipment follows (in millions): December 31, Additions / (Depreciation) December 31, Land $ 1.2 $ — $ 1.2 Buildings and leasehold improvements 4.8 0.2 5.0 Machinery and equipment 2.0 1.8 3.8 Other 1.1 0.2 1.3 Property, plant and equipment, gross 9.1 2.2 11.3 Accumulated depreciation (3.6) (0.7) (4.3) Property, plant and equipment, net $ 5.5 $ 1.5 $ 7.0 Depreciation expense was $0.7 million in 2023, $0.6 million in 2022 and $0.6 million in 2021.

Intangible Assets

Intangible Assets	12 Months Ended
	Dec. 31, 2023
Goodwill and Intangible Assets Disclosure [Abstract]
Intangible Assets	INTANGIBLE ASSETS, NET Intangible assets originated from the Company’s reorganization and application of fresh start accounting as of the date the Company emerged from bankruptcy, September 30, 2014, and reflect the conditions at that time. The intangible asset related to the Company’s Order Book is amortized as the Order Book, existing at emergence, is reduced, principally as a result of deliveries to customers. The intangible asset related to customer relationships is amortized using the straight-line method over the estimated average useful life of 15 years. Amortization expense is presented below gross profit on the Consolidated Statements of Operations. Intangible asset balances are as follows (in millions): December 31, 2023 December 31, 2022 Gross Carrying Amount Accumulated Amortization Net Amount Gross Carrying Amount Accumulated Amortization Net Amount Sales order book $ 54.6 $ 41.6 $ 13.0 $ 54.6 $ 39.9 $ 14.7 Customer relationships 68.9 42.5 26.4 68.9 37.9 31.0 Total $ 123.5 $ 84.1 $ 39.4 $ 123.5 $ 77.8 $ 45.7 The amount of amortization expense for intangible assets in each of the succeeding years is estimated to be as follows (in millions): 2024 $ 8.9 2025 9.1 2026 7.4 2027 6.0 2028 4.6 Thereafter 3.4 Total $ 39.4

Accounts Payable and Accrued Li

Accounts Payable and Accrued Liabilities	12 Months Ended
	Dec. 31, 2023
Accounts Payable and Accrued Liabilities [Abstract]
Accounts Payable and Accrued Liabilities [Text Block]	ACCOUNTS PAYABLE AND ACCRUED LIABILITIES Components of accounts payable and accrued liabilities follow (in millions): December 31, 2023 2022 Trade payables $ 6.1 $ 5.9 Compensation and employee benefits 21.1 15.7 Postretirement health and life benefit obligations - current 10.1 7.3 Accrued HALEU Operation Contract loss — 20.0 Short-term inventory loan 14.3 9.9 Operating lease liability 1.4 3.3 Other accrued liabilities 3.2 3.4 Total accounts payable and accrued liabilities $ 56.2 $ 65.5

Debt

Debt	12 Months Ended
	Dec. 31, 2023
Debt Disclosure [Abstract]
Debt	DEBT A summary of debt follows (in millions): December 31, 2023 December 31, 2022 Maturity Current Long-Term Current Long-Term 8.25% Notes: Feb. 2027 Principal $ — $ 74.3 $ — $ 74.3 Interest 6.1 15.3 6.1 21.4 Total $ 6.1 $ 89.6 $ 6.1 $ 95.7 Interest on the 8.25% Notes maturing in February 2027 is payable semi-annually in arrears as of February 28 and August 31 based on a 360-day year consisting of twelve 30-day months. The 8.25% Notes mature on February 28, 2027. The 8.25% Notes were issued in connection with a troubled debt restructuring, therefore, all future interest payment obligations on the 8.25% Notes are included in the carrying value of the 8.25% Notes. As a result, interest payments are reported as a reduction in the carrying value of the 8.25% Notes and not as interest expense. As of December 31, 2023, and December 31, 2022, $6.1 million of interest is recorded as current and classified as Current Debt in the Consolidated Balance Sheet. The 8.25% Notes rank equally in right of payment with all of the Company’s existing and future unsubordinated indebtedness other than its Issuer Senior Debt and its Limited Secured Acquisition Debt (each as defined below). The 8.25% Notes rank senior in right of payment to all of the Company’s existing and future subordinated indebtedness and to certain limited secured acquisition indebtedness of the Company (the “Limited Secured Acquisition Debt”). The Limited Secured Acquisition Debt includes (i) any indebtedness, the proceeds of which are used to finance all or a portion of an acquisition or similar transaction if any lender’s lien is solely limited to the assets acquired in such a transaction and (ii) any indebtedness, the proceeds of which are used to finance all or a portion of the American Centrifuge project or another next generation enrichment technology if any lender’s lien is solely limited to such assets, provided that a lien securing the 8.25% Notes that is junior with respect to the lien securing such indebtedness will be limited to the assets acquired with such Limited Secured Acquisition Debt. The indenture governing the 8.25% Notes includes restrictions on the ability of Enrichment Corp. to transfer cash and other assets to the Company, which could constrain the Company’s ability to pay dividends on its Common Stock or to fund its commitments or the commitments of its other subsidiaries, subject to certain exceptions, such as the transfer of inventory and other assets in the ordinary course of business of Enrichment Corp. The indenture also restricts the Company’s ability to engage in certain mergers or acquisitions and requires the Company to offer to repurchase all such outstanding notes at 101% of their outstanding principal amount in the event of certain change of control events. The 8.25% Notes are subordinated in right of payment to certain indebtedness and obligations of the Company, as described in the indenture governing the 8.25% Notes (the “Issuer Senior Debt”), including (i) any indebtedness of the Company (inclusive of any indebtedness of Enrichment Corp.) under a future credit facility up to $50 million with a maximum net borrowing of $40 million after taking into account any minimum cash balance (unless a higher amount is approved with the consent of the holders of a majority of the aggregate principal amount of the 8.25% Notes then outstanding), (ii) any revolving credit facility to finance inventory purchases and related working capital needs, and (iii) any indebtedness of the Company to Enrichment Corp. under the secured intercompany notes. The 8.25% Notes are guaranteed on a subordinated and limited basis by, and secured by substantially all of the assets of, Enrichment Corp. The Enrichment Corp. guarantee is a secured obligation and ranks equally in right of payment with all existing and future unsubordinated indebtedness of Enrichment Corp. (other than Designated Senior Claims (as defined below) and Limited Secured Acquisition Debt) and senior in right of payment to all existing and future subordinated indebtedness of Enrichment Corp. and Limited Secured Acquisition Debt. The Enrichment Corp. guarantee is subordinated in right of payment to certain obligations of, and claims against, Enrichment Corp. described in the indenture governing the 8.25% Notes (collectively, the “Designated Senior Claims”), including obligations and claims: • under a future credit facility up to $50 million with a maximum net borrowing of $40 million after taking into account any minimum cash balance; • under any revolving credit facility to finance inventory purchases and related working capital needs; • held by or for the benefit of the Pension Benefit Guaranty Corporation pursuant to any settlement (including any required funding of pension plans); and • under surety bonds or similar obligations held by or on behalf of the U.S. government pursuant to regulatory requirements. The lien securing the Enrichment Corp. guarantee of the 8.25% Notes is junior in priority with respect to the lien securing Limited Secured Acquisition Debt, which is limited to the assets acquired with such Limited Secured Acquisition Debt.

Fair Value Measurements

Fair Value Measurements	12 Months Ended
	Dec. 31, 2023
Fair Value Disclosures [Abstract]
Fair Value Measurements	FAIR VALUE Fair value is the price that would be received from selling an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. When determining the fair value of assets and liabilities, the following hierarchy is used in selecting inputs, with the highest priority given to Level 1, as these are the most transparent or reliable: • Level 1 assets include investments with quoted prices in active markets that the Company has the ability to liquidate as of the reporting date. • Level 2 assets include investments in U.S. government agency securities, corporate and municipal debt whose estimates are valued based on observable inputs, other than quoted prices. • Level 3 assets include investments with unobservable inputs, such as third-party valuations, due to little or no market activity. Financial Instruments Recorded at Fair Value (in millions): December 31, 2023 December 31, 2022 Level 1 Level 2 Level 3 Total Level 1 Level 2 Level 3 Total Assets: Cash and cash equivalents $ 201.2 $ — $ — $ 201.2 $ 179.9 $ — $ — $ 179.9 Deferred compensation asset (a) 3.3 — — 3.3 2.4 — — 2.4 Liabilities: Deferred compensation obligation (a) $ 3.3 $ — $ — $ 3.3 $ 2.4 $ — $ — $ 2.4 (a) The deferred compensation obligation represents the balance of deferred compensation plus net investment earnings. The deferred compensation plan is funded through a rabbi trust. Trust funds are invested in mutual funds for which unit prices are quoted in active markets and are classified within Level 1 of the valuation hierarchy. There were no transfers between Level 1, 2 or 3 during the periods presented. Other Financial Instruments As of December 31, 2023, and 2022, the Consolidated Balance Sheets carrying amounts for Accounts Receivable , Accounts Payable and Accrued Liabilities (excluding the deferred compensation obligation described above), and Payables under Inventory Purchase Agreements approximate fair value because of their short-term nature. The carrying value and estimated fair value of long-term debt are as follows (in millions): December 31, 2023 December 31, 2022 Carrying Value Estimated Fair Value (a) Carrying Value Estimated Fair Value (a) 8.25% Notes $ 95.7 (b) $ 71.7 $ 101.8 (b) $ 68.8 (a) Based on bid/ask quotes as of or near the balance sheet date, which are considered Level 2 inputs based on the frequency of trading. (b) The carrying value of the 8.25% Notes consists of the principal balance of $74.3 million and the sum of current and non current interest payment obligations until maturity. Refer to Note 8 , Debt

Pension and Postretirement Heal

Pension and Postretirement Health and Life Benefits	12 Months Ended
	Dec. 31, 2023
Retirement Benefits, Description [Abstract]
Pension and Postretirement Health and Life Benefits	PENSION AND POSTRETIREMENT HEALTH AND LIFE BENEFITS The Company provides retirement benefits to certain employees and retirees under two qualified defined benefit pension plans, one postretirement health and life benefit plan and two disqualified plans. There are approximately 2,900 employees and retirees covered by qualified defined benefit pension plans providing retirement benefits based on compensation and years of service, and approximately 2,900 employees and retirees covered by postretirement health and life benefit plans. The DOE retained the obligation for postretirement health and life benefits for workers who retired prior to July 28, 1998. Pursuant to non-qualified supplemental pension plans, Centrus provides certain executive officers additional retirement benefits in excess of qualified plan limits imposed by tax law based on a targeted benefit objective. Employees hired on or after September 1, 2008, who are not covered by a collective bargaining agreement that provides for participation do not participate in a qualified defined benefit pension plan or postretirement health and life benefit plans. Changes in the projected benefit obligations and plan assets and the funded status of the plans follow: Defined Benefit Pension Plans Postretirement Health ($ millions) Year Ended December 31, Year Ended December 31, 2023 2022 2023 2022 Changes in Benefit Obligations: Obligations at beginning of period $ 527.3 $ 696.2 $ 95.3 $ 131.1 Actuarial (gains) losses, net (25.2) (138.0) 1.4 (27.0) Service costs 2.9 2.7 — — Interest costs 27.8 19.1 5.0 3.5 Benefits paid from plan assets (50.2) (50.0) (10.4) (12.3) Benefits paid from Company assets (0.4) (0.4) — — Plan amendments 0.4 — — — Settlements (171.4) — — — Administrative expenses paid (3.0) (2.3) — — Obligations at end of period 308.2 527.3 91.3 95.3 Changes in Plan Assets: Fair value of plan assets at beginning of period 483.3 672.7 3.5 9.2 Actual return on plan assets 31.8 (137.1) 0.1 (0.1) Company contributions 0.4 0.4 6.8 6.7 Benefits paid (50.6) (50.4) (10.4) (12.3) Settlements (171.4) — — — Administrative expenses paid (3.0) (2.3) — — Fair value of plan assets at end of period 290.5 483.3 — 3.5 Unfunded status at end of period $ (17.7) $ (44.0) $ (91.3) $ (91.8) Amounts recognized in assets and liabilities: Current liabilities $ (0.4) $ (0.4) $ (10.1) $ (7.3) Non current liabilities (17.3) (43.6) (81.2) (84.5) $ (17.7) $ (44.0) $ (91.3) $ (91.8) Amounts in accumulated other comprehensive income (loss), pre-tax: Prior service credit $ (0.1) $ (0.7) $ (1.8) $ (1.9) The current liabilities reflect expected contributions for benefit payments for the non-qualified plans and the postretirement health and life benefit plans in the following year. The discount rates below, rounded to the nearest 0.1%, are the estimated rates at which the benefit obligations could be effectively settled on the measurement date and are based on yields of high quality fixed income investments whose cash flows match the timing and amount of expected benefit payments of the plans. Plan assets and benefit obligations are remeasured each year as of the balance sheet date resulting in differences between actual and projected results for the year. These actuarial gains and losses are recognized in the Consolidated Statements of Operations in the fourth quarter. In addition, an interim remeasurement and recognition of gains or losses may be required for a plan during the year when lump sum payments exceed, or are expected to exceed, the sum of the service cost and interest cost components of the annual net periodic benefit cost for that plan for the current year. There were no interim remeasurements in 2022. During the third quarter of 2023, the Company determined that it was probable that lump sum payouts for 2023 would be greater than the annual service and interest cost components of the annual net periodic benefit cost for one of its defined benefit pension plans, triggering a remeasurement. The Company’s defined benefit obligations for its pension plans was $527.3 million at December 31, 2022, of which $30.6 million related to this plan. The interim remeasurement resulted in a decrease in the benefit obligation and a corresponding net actuarial gain of $0.9 million in 2023. The defined benefit pension plans currently allow for a lump sum payment option to (a) active employees who are terminated as a result of Company reductions in force and (b) terminated vested participants who have not yet begun receiving their benefits and have been terminated as a result of a reduction in force by the Company, or due to voluntary termination or involuntary termination, other than involuntary termination as a termination for cause. On October 12, 2023, the Company entered into an agreement with an insurer (“Insurer”) for one of its defined benefit plans to purchase a group annuity contract and transferred approximately $186.5 million of its pension plan obligations to the Insurer. The purchase of the group annuity contract was funded directly by assets of the pension plan of approximately $171.4 million. The purchase resulted in a transfer of benefit administrative responsibilities for approximately 1,400 beneficiaries effective December 1, 2023. The Company recorded income related to the pension settlement in the fourth quarter of $28.6 million, which was included in Nonoperating Components of Net Periodic Benefit Income in its Consolidated Statements of Operations. Projected benefit obligations are based on actuarial assumptions including possible future increases in compensation. Accumulated benefit obligations are based on actuarial assumptions but do not include possible future increases in compensation. Effective August 2013, accrued benefits under the defined benefit pension plans are fixed and no longer increase to reflect changes in compensation or company service. Therefore, the accumulated benefit obligation equaled the projected benefit obligation of $308.2 million and $527.3 million as of December 31, 2023 and 2022, respectively. As of December 31, 2023 and 2022, none of Centrus’ plans had fair value of plan assets in excess of accumulated benefit obligations. Components of Net Periodic Benefit Costs and Other Amounts Recognized in Other Comprehensive Income The Company reports service costs for its defined benefit pension plans and its postretirement health and life benefit plans in Cost of Sales and Selling, General and Administrative Expenses . The remaining components of net periodic benefit (credits) costs are reported as Nonoperating Components of Net Periodic Benefit Income. Defined Benefit Pension Plans Postretirement Health (in millions) Year Ended December 31, Year Ended December 31, 2023 2022 2021 2023 2022 2021 Net Periodic Benefit (Credits) Costs Service costs $ 2.9 $ 2.7 $ 2.7 $ — $ — $ — Interest costs 27.8 19.1 18.1 5.0 3.5 3.4 Expected return on plan assets (31.0) (35.6) (38.3) (0.1) (0.1) — Amortization of prior service credits, net (0.2) (0.2) (0.2) (0.1) (0.1) (0.1) Actuarial (gains) losses, net (26.0) 34.7 (48.2) 1.4 (26.9) (2.3) Net periodic benefit (credits) costs $ (26.5) $ 20.7 $ (65.9) $ 6.2 $ (23.6) $ 1.0 Other Changes in Plan Assets and Benefit Obligations Recognized in Other Comprehensive Income (Loss) Amortization of prior service costs, net $ — $ — $ — $ (1.8) $ (1.9) $ (2.0) Prior service credit (0.1) (0.7) (0.9) — — — Total recognized in other comprehensive loss, pre-tax $ (0.1) $ (0.7) $ (0.9) $ (1.8) $ (1.9) $ (2.0) Total recognized in net periodic benefit costs (income) and other comprehensive income (loss), pre-tax $ (26.6) $ 20.0 $ (66.8) $ 4.4 $ (25.5) $ (1.0) Net periodic benefit costs include service and interest costs of providing pension benefits that are accrued over the years employees render service. Prior service costs or credits are amortized over the employees’ average remaining years of service from age 40 until the date of full benefit eligibility or the average expected future lifetime of all plan participants, as applicable. Participants in the postretirement health and life benefit plans are generally eligible for benefits at retirement after age 50 with 10 years of continuous credited service at the time of retirement. On September 7, 2021, the Company collected $43.5 million from the DOE, of which $33.8 million was contributed to the pension plan in September 2021 for its subsidiary Enrichment Corp. and $9.7 million was deposited in October 2021 in a trust for payment of postretirement health benefits payable by Enrichment Corp. Refer to Note 2, Revenue and Contracts with Customers. Effective January 1, 2014, or for certain plan participants formerly represented by a collective bargaining unit, January 1, 2015, plan participants age 65 or older (“post-65”) have access to a range of medical plan choices with varying costs and benefits through a Medicare Exchange implemented by the Company. The Company provides an annual stipend for each of the post-65 retirees and post-65 spouses who enroll in the coverage through the exchange. Depending on the level of benefits elected by the participant, the participant may be required to make contributions in excess of the stipend amount. The transition to the post-65 Medicare Exchange was reflected as a plan amendment that reduced plan obligations by $6.8 million as of December 31, 2014. This reduction in obligation was recognized in other comprehensive income in 2014 as a prior service credit. The prior service credit is being amortized into net periodic benefit cost as a credit over time. The post-65 Medicare Exchange stipend amount was increased for 2017. This increase in obligation of $3.6 million as of December 31, 2016, was recognized in other comprehensive income in 2016 as a prior service cost and is being amortized into net periodic benefit cost over time. The post-65 Medicare Exchange stipend amount was increased in 2018, as specified in a settlement agreement with the former collective bargaining unit. The settlement agreement also specifies the addition of catastrophic drug coverage effective January 1, 2019. The benefit enhancement for 2019 has been applied to all post-65 participants regardless of past representation by the collective bargaining agreement. The increase in obligation of $10.0 million as a result of the settlement agreement was recognized in net periodic benefit costs in 2017 as a plan change resulting from a legal settlement and is reported in Nonoperating Components of Net Periodic Benefit Income . The defined benefits pension plans were amended in March 2019 making permanent the option for pension-eligible employees to receive a lump sum payment upon termination, regardless of benefit size. The effect of these plan changes has been added to Accumulated Other Comprehensive Income (Loss) as an unrecognized prior service cost to be amortized over the average future service of active employees starting in 2020. Assumptions Used to Determine Net Periodic Benefit Costs Defined Benefit Pension Plans Postretirement Health Year Ended December 31, Year Ended December 31, 2023 2022 2021 2023 2022 2021 Discount rate 5.2% 5.5% 2.8% 5.2% 5.5% 2.8% Expected return on plan assets 6.8% 5.5% 6.3% 4.0% 0.8% — The expected return on plan assets is based on the weighted average of long-term return expectations for the composition of the plans’ equity and debt securities. Expected returns on equity securities are based on historical long-term returns of equity markets. Expected returns on debt securities are based on the current interest rate environment. Healthcare cost trend rates used to measure postretirement health benefit obligations follow: December 31, 2023 2022 Healthcare cost trend rate for the following year 7.0% 7.0% Long-term rate that the healthcare cost trend rate gradually declines to 5% 5% Year that the healthcare cost trend rate is expected to reach the long-term rate 2032 2031 Benefit Plan Assets Independent advisors manage investment assets of Centrus’ defined benefit pension plans and postretirement health and life benefit plans. Centrus has the fiduciary responsibility for reviewing performance of the various investment advisors. The goal of the investment policy of the plans is to maximize portfolio returns within reasonable and prudent levels of risk in order to meet projected liabilities and maintain sufficient cash to make timely payments of all participant benefits. Risk is reduced by diversifying plan assets and following a strategic asset allocation approach. Additionally, as the plans are frozen and funding status has improved, the Company has shifted the investment allocations to lower risk investments in order to minimize market exposure and will continue to do so based upon approved funding milestones. Asset classes and target weights are adjusted periodically to optimize the long-term portfolio risk/return trade off, to provide liquidity for benefit payments, and to align portfolio risk with the underlying obligations. The investment policy of the plans prohibits the use of leverage, direct investments in tangible assets, or any investment prohibited by applicable laws or regulations. The allocation of plan assets between equity and debt securities and the target allocation range by asset category for the defined benefit pension plans follows: December 31, 2023 2022 2024 Target Equity securities 42 % 36 % 35 - 40% Debt securities 57 % 62 % 55 - 60% Cash 1 % 2 % 0 - 5% 100 % 100 % Plan assets are measured at fair value. Following are the plan investments as of December 31, 2023 and 2022, categorized by the fair value hierarchy levels described in Note 10, Fair Value : Defined Benefit Pension and Postretirement Health and Life Benefit Plans (in millions) Level 1 Level 2 Level 3 Total 2023 2022 2023 2022 2023 2022 2023 2022 U.S. government securities $ — $ — $ — $ — $ — $ — $ — $ — Corporate debt — — 9.6 60.3 — — 9.6 60.3 Municipal bonds and non-U.S. government securities — — — — — — — — Mutual funds (b) 245.7 320.4 — — — — 245.7 320.4 Mortgage and asset backed securities — — — — — — — — Fair value of investments by hierarchy level $ 245.7 $ 320.4 $ 9.6 $ 60.3 $ — $ — 255.3 380.7 Investments measured at NAV (a) 35.2 105.8 Accrued interest receivable 0.5 0.6 Unsettled transactions — (0.3) Plan assets $ 291.0 $ 486.8 (a) Equity, bond and money market investments held in collective trusts are valued based on the NAV provided by the administrator of the funds. The NAV for each fund is based on the underlying assets owned by the fund, less any expenses accrued against the fund, divided by the number of fund shares outstanding. While the underlying investments are traded on an exchange, the funds are not. Fair values for the collective trust investments are measured using the NAVs as a practical expedient and are not categorized in the fair value hierarchy. (b) Postretirement Health and Life Benefit Plan assets of $3.5 million as of December 31, 2022, are all included within Level 1 mutual funds. During 2023, the remaining assets of the Postretirement Health and Life Benefit Plan were expended and any related benefit costs are now primarily funded as incurred. Benefit Plan Cash Flows The Company expects to contribute $0.4 million to the qualified defined benefit pension plans, $0.4 million to the non-qualified defined benefit pension plans, and $10.1 million to the postretirement health and life benefit plans in 2024. There is no required contribution for the postretirement health and life benefit plans under Employee Retirement Income Security Act of 1974. Estimated future benefit plan payments follow (in millions): Defined Benefit Pension Plans Postretirement Health and Life Benefit Plans 2024 $ 30.0 $ 10.1 2025 28.5 9.5 2026 28.6 9.0 2027 26.9 8.4 2028 26.1 7.8 2029 to 2033 120.1 31.6 Other Plans The Company sponsors a 401(k) defined contribution plan for employees. Employee contributions are matched at established rates. Amounts contributed are invested in a range of investment options available to participants and the funds are administered by an independent trustee. Matching cash contributions by the Company amounted to $2.3 million, $2.1 million, and $2.0 million in 2023, 2022, and 2021. Under the Executive Deferred Compensation Plan, qualified employees may defer compensation on a tax-deferred basis subject to plan limitations. Any matching contributions under the Company’s 401(k) plan that are foregone due to annual compensation limitations of the Code are eligible to be received from the Company under the Executive Deferred Compensation Plan, provided that the employee deferred the maximum allowable pre-tax contribution in the 401(k) plan . The Company matching contributions amounted to less than $0.1 million in 2023, 2022, and 2021.

Compensation Related Costs, Ret

Compensation Related Costs, Retirement Benefits	12 Months Ended
	Dec. 31, 2023
Retirement Benefits [Abstract]
Compensation and Employee Benefit Plans	EXECUTIVE SEVERANCE PLAN The Company maintains the Severance Plan which provides severance benefits for covered executives. In addition, the Company also enters into employee agreements with key executives which incorporate severance benefits, including continuation of certain insurance benefits. The benefits payable under the Severance Plan (as well as applicable employment agreements) outline benefits based on salary level, amongst other variables. Accordingly, as the severance expenses are part of an on-going benefit arrangement, the Company recognizes the expense when payment of the severance is probable and can be reasonably estimated in accordance with ASC 712, Compensation — Nonretirement Postemployment Benefits . In December 2023, the Company recorded a severance charge of $3.6 million related to the separation of one executive, which was recorded in Special Charges for Workforce Reductions expenses in the Consolidated Statements of Operations. The Company expects the majority of the severance charge to be paid out in 2024, excluding the costs for the continuation of insurance benefits. The Company’s severance expenses were $3.6 million, $0.5 million, and $0 million for the years ended December 31, 2023, 2022, and 2021, respectively.

Stock-Based Compensation

Stock-Based Compensation	12 Months Ended
	Dec. 31, 2023
Share-Based Payment Arrangement, Noncash Expense [Abstract]
Stock-Based Compensation	STOCK-BASED COMPENSATION The Company’s 2014 Plan authorizes the issuance of stock options, SARs, restricted stock units, restricted stock, notional stock units, performance awards, dividend equivalent rights, and other stock-based awards, as well as cash-based awards, to employees, officers, directors, and other individuals providing services to the Company or its affiliates. As disclosed in Note 16, Stockholder’s Equity , in February 2021, the Company increased the available shares of Class A Common Stock under the Company’s 2014 Plan by an additional 700,000 shares. The 2014 Plan currently authorizes the issuance of up to 1,900,000 shares. As of December 31, 2023, there were 561,704 shares available for future awards. In January 2019, the Company adopted the 2019 Equity Incentive Plan, which is subject to the terms of the 2014 Plan, under which participating employees are eligible to receive grants of equity awards such as notional stock units and SARs. Under this plan, the Company has granted awards that are subject to either cliff-based or performance-based vesting. The cliff-based awards vest after three years of service. The performance-based awards vest if the Company reaches or exceeds a pre-defined net income target for the three-year award term. Equity awards may be payable in common stock, cash, or a combination of both, at the discretion of the Board of Directors. Compensation costs for awards that are likely to be settled with cash payments are remeasured each reporting period based on the closing price of the Company’s Class A Common Stock. These cumulative vested costs are accrued in Accounts Payable and Accrued Liabilities or Other Long-Term Liabilities . Equity awards that are payable in stock are accounted for as equity and compensation costs are amortized on a straight-line basis over the vesting period. In 2019, under the 2014 Plan, the Company awarded notional stock units to participating executives for the three-year period ending December 31, 2021. As the original award, at grant date, was expected to be settled in cash, the Company had recorded cumulative compensation costs in Other Long-Term Liabilities at December 31, 2020. There were 206,183 notional stock units (two-thirds of these awards) paid in shares in April 2021, with the remainder paid in April 2022. As of March 31, 2021, the Company reclassified these shares to equity as the Board of Directors approved settlement in shares. The related obligation of $7.5 million was reclassified from Accounts Payable and Accrued Liabilities to Excess of Capital over Par Value in the first quarter of 2021 based on the market share price at the time of the Board of Directors’ decision. In the second quarter of 2021, the Company withheld $2.4 million of shares to fund the grantees’ tax withholding obligations relating to the April 2021 interim payment. In 2020, the Company awarded participating executives notional stock units and stock appreciation rights for the three-year period ending April 26, 2023. These equity awards could have been paid in common stock, cash, or a combination of both at the discretion of the Board of Directors. The cumulative vested costs were accrued in Other Long-Term Liabilities as at that time they were likely to be settled in cash . In September 2021, the Company awarded participating executives notional stock units and SARs. The awards granted will be paid in shares on or before May 1, 2024, provided that a defined performance condition is achieved. In order to receive the award, the total cumulative net income as reported on the Company’s Form 10-Ks for the years ending December 31, 2021, 2022, and 2023 must be equal to or greater than $160 million. The grant date fair value of notional stock units is determined based on the closing price of Class A Common Stock on the grant date. The grant date fair value of the SARs were determined based on the Black-Scholes option-pricing model. The Company has concluded that it is probable that the performance condition will be achieved and therefore has recorded compensation cost. Compensation costs for these notional stock units and SARs are amortized to expense on a straight-line basis over the vesting period. In February 2022, the Compensation, Nominating and Governance Committee of the Board of Directors determined that remaining notional stock units granted in 2019 and 2020 would be paid in shares of the Company’s Class A Common Stock. The related obligation of $10.6 million was reclassified from Accounts Payable and Accrued Liabilities to Excess of Capital over Par Value in the first quarter of 2022 based on the market share price at the time of the Board’s decision. In the first quarter of 2022, the Company withheld $1.9 million of shares that vested during the period for the purpose of funding the grantees’ tax withholding obligations under the terms of the stock-based compensation plan. In March 2022, restricted stock was granted to participating executives with a vesting period ending in March 2025. In March 2023, restricted stock was granted to participating executives with a vesting period ending in March 2026. The March 2022 and 2023 awards are payable in shares of the Company’s Class A Common Stock and the grant-date value is included in Excess of Capital over Par Value as the value is amortized over the vesting period. The plan payouts for the 2020-2022 performance period were settled in Class A Common Stock in March and April 2023. In the first quarter of 2023, the Company withheld $1.9 million of shares that vested during the period for the purpose of funding the grantees’ tax withholding obligations under the terms of the stock-based compensation plan. Compensation cost for restricted stock units and stock options is measured at the grant date, based on the fair value of the award, and is recognized on a straight-line basis over the requisite service period. As of December 31, 2023, there was $1.4 million of unrecognized compensation cost, adjusted for actual forfeitures, related to non-vested stock-based payments granted, all of which relates to restricted stock units. That cost is expected to be recognized over a weighted-average period of 48 months. A summary of stock-based compensation costs is as follows (in millions): Year Ended December 31, 2023 2022 2021 Notional stock units and stock appreciation rights $ 1.0 $ 0.9 $ 11.6 Restricted stock 0.4 0.2 — BOD and employee restricted stock units 0.9 0.7 0.5 Stock options — 0.1 0.1 Total stock-based compensation costs $ 2.3 $ 1.9 $ 12.2 Total recognized tax benefit $ (0.3) $ (0.2) $ (1.5) The total recognized tax benefit is reported at the federal statutory rate net of the tax valuation allowance. Board Restricted Stock Units Non-employee, independent directors are granted restricted stock units as part of their compensation for serving on the Board of Directors. Settlement of these restricted stock units is made in shares of Class A Common Stock upon the director’s retirement, other end of service, or vesting, in accordance with the terms of the grant agreement. The restricted stock units generally vest over one year; however, vesting is accelerated upon (1) the director attaining eligibility for retirement, (2) termination of the director’s service by reason of death or disability, or (3) a change in control. As of December 31, 2023, approximately 160,000 shares of restricted stock units could potentially be converted to Class A Common Stock once vested and settled. The following table summarizes Centrus’ board restricted stock units activity: Shares (in thousands) Weighted Average Grant Date Fair Value (per share) Nonvested at December 31, 2020 47 $10.38 Granted 20 $25.13 Vested (47) $10.38 Forfeited — — Nonvested at December 31, 2021 20 $25.13 Granted 28 $38.80 Vested (20) $25.13 Forfeited — — Nonvested at December 31, 2022 28 $38.80 Granted 17 $35.95 Vested (28) $38.80 Forfeited — — Nonvested at December 31, 2023 17 $35.95 Employee Restricted Stock Units In 2021, certain employees were granted restricted stock units as part of their compensation. The restricted stock units generally vest over three years and will be settled in Class A Common Stock upon vesting. As of December 31, 2023, approximately 1,000 shares of these restricted stock units could potentially be converted to Class A Common Stock once vested and settled. In December 2023, the Company granted 20,000 restricted stock units to the new CEO as part of his compensation. The restricted stock units generally vest over five years and will be settled in Class A Common Stock. As of December 31, 2023, approximately 20,000 shares of these restricted stock units could potentially be converted to Class A Common Stock once vested and settled. The following table summarizes Centrus’ employee restricted stock units activity: Shares Weighted Average Grant Date Fair Value (per share) Nonvested at December 31, 2020 — — Granted 4 $24.01 Vested — — Forfeited — — Nonvested at December 31, 2021 4 $24.01 Granted — — Vested (1) $24.01 Forfeited — — Nonvested at December 31, 2022 3 $24.01 Granted 20 $55.54 Vested (1) $24.01 Forfeited (1) $24.01 Nonvested at December 31, 2023 21 $54.04 Stock Options The intrinsic value of an option, if any, represents the excess of the fair value of the common stock over the exercise price. The fair value of stock option awards is estimated using the Black-Scholes option pricing model, which includes a number of assumptions including Centrus’ estimates of stock price volatility, employee stock option exercise behaviors, future dividend payments, and risk-free interest rates. The expected term of options granted is the estimated period of time from the beginning of the vesting period to the date of expected exercise or other settlement, based on historical exercises and post-vesting terminations. Centrus has estimated the expected term using the simplified method described in SEC Staff Accounting Bulletin Topic 14, Share-Based Payment , due to the lack of historical exercise and post-vesting termination information available for the Company since its reorganization. Future stock price volatility is estimated based on the Company’s historical volatility. The risk-free interest rate for the expected option term is based on the U.S. Treasury yield curve in effect at the time of grant. No cash dividends are expected in the foreseeable future, and therefore, an expected dividend yield of zero is used in the option valuation model. There were no option grants in the years ended December 31, 2023, 2022, and 2021. Stock options vest and become exercisable in equal annual installments over a three or four year period and expire ten years from the date of grant. A summary of stock option activity follows: Stock Options (in thousands) Weighted Average Exercise Price Weighted Average Remaining Contractual Life in Years Aggregate Intrinsic Value (in millions) Outstanding at December 31, 2020 411 $4.18 5.3 $7.8 Granted — — — — Exercised (217) $4.17 — — Forfeited/Cancelled — — — — Outstanding at December 31, 2021 194 $4.18 4.4 $8.9 Granted — — — — Exercised (98) $4.00 — — Forfeited/Cancelled — — — — Outstanding at December 31, 2022 96 $4.37 2.2 $2.7 Granted — — — — Exercised — — — — Forfeited/Cancelled — — — — Outstanding at December 31, 2023 96 $4.37 0.3 $4.8 Exercisable at December 31, 2023 96 $4.37 0.3 $4.8 Stock options outstanding and options exercisable at December 31, 2023, are as follows: Stock Exercise Price Options Outstanding (thousands) Remaining Contractual Life in Years Options Exercisable (thousands) $4.37 96 0.3 96 Stock Appreciation Rights - 2020 Award The intrinsic value of a SAR, if any, represents the excess of the fair value of the common stock over the exercise price. The fair value of SAR awards is estimated using the Black-Scholes option pricing model, which includes a number of assumptions including Centrus’ estimates of stock price volatility, expected term, future dividend payments, and risk-free interest rates. These SARs generally have a defined term of three years from award and are automatically exercised at the end of its term. Future stock price volatility is estimated based on the Company’s historical volatility. The risk-free interest rate for the expected term is based on the U.S. Treasury yield curve in effect at the time of grant. No cash dividends are expected in the foreseeable future and, therefore, an expected dividend yield of zero is used in the valuation model. A summary of SARs with time-based vesting granted under the 2014 Plan for the year ended December 31, 2023, are as follows: Stock Appreciation Rights (in thousands) Weighted Average Exercise Price Weighted Average Remaining Contractual Life in Years Aggregate Intrinsic Value (in millions) Outstanding at December 31, 2020 84 $5.53 2.3 $1.5 Granted — — — — Exercised — — — — Forfeited/Cancelled — — — — Outstanding at December 31, 2021 84 $5.53 1.3 $3.7 Granted — — — — Exercised — — — — Forfeited/Cancelled (14) $5.53 — — Outstanding at December 31, 2022 70 $5.53 0.3 $2.7 Granted — — — — Exercised (74) $5.53 — — Forfeited/Cancelled 4 $5.53 — — Outstanding at December 31, 2023 — — — — Exercisable at December 31, 2023 — — — — Stock Appreciation Rights (Performance Condition) - 2021 Award The intrinsic value of a SAR, if any, represents the excess of the fair value of the common stock over the exercise price. The fair value of SAR awards is estimated using the Black-Scholes option pricing model, which includes a number of assumptions including Centrus’ estimates of stock price volatility, expected term, future dividend payments, and risk-free interest rates. These SARs generally have a defined term of three years from award and are automatically exercised at the end of its term if the performance condition has been met. Future stock price volatility is estimated based on the Company’s historical volatility. The risk-free interest rate for the expected term is based on the U.S. Treasury yield curve in effect at the time of grant. No cash dividends are expected in the foreseeable future and, therefore, an expected dividend yield of zero is used in the valuation model. A summary of SARs with performance-based vesting granted under the 2014 Plan in the year ended December 31, 2023, are as follows: Stock Appreciation Rights (Performance Condition) (in thousands) Weighted Average Exercise Price Weighted Average Remaining Contractual Life in Years Aggregate Intrinsic Value (in millions) Outstanding at December 31, 2020 — — — — Granted 21 $19.44 — — Exercised — — — — Forfeited/Cancelled — — — — Outstanding at December 31, 2021 21 $19.44 2.3 $0.6 Granted — — — — Exercised — — — — Forfeited/Cancelled (3) $19.44 — — Outstanding at December 31, 2022 18 $19.44 1.3 — Granted — — — — Exercised — — — — Forfeited/Cancelled (1) $19.44 — — Outstanding at December 31, 2023 17 $19.44 0.2 $0.3 Exercisable at December 31, 2023 17 $19.44 0.2 $0.3 The weighted-average assumptions used in the valuation models to determine the fair value of SARs granted to employees under the 2014 Plan are as follows: Year Ended December 31, 2023 2022 2021 Stock Appreciation Rights Granted (in thousands) n/a n/a 21.0 Average Risk-Free Rate n/a n/a 0.3% Expected Volatility n/a n/a 82.8% Expected Term (Years) n/a n/a 2.5 Dividend Yield n/a n/a — Notional Stock Units - 2019 and 2020 Awards A summary of notional stock units with time-based vesting granted under the 2014 Plan for the year ended December 31, 2023, are as follows: Shares (thousands) Weighted Average Grant Date Fair Value (per share) Nonvested at December 31, 2020 571 $3.68 Granted — — Vested (319) — Forfeited/Cancelled — — Nonvested at December 31, 2021 252 $4.33 Granted — — Vested (128) $3.16 Forfeited (2) $5.53 Nonvested at December 31, 2022 122 $5.53 Granted — — Vested (104) $5.53 Forfeited (18) $5.53 Nonvested at December 31, 2023 — — Notional Stock Units (Performance Condition) - 2021 Award A summary of notional stock units with performance-based vesting granted under the 2014 Plan for the year ended December 31, 2023, are as follows: Shares Weighted Average Grant Date Fair Value (per share) Nonvested at December 31, 2020 — — Granted 10 $39.55 Vested — — Forfeited — — Nonvested at December 31, 2021 10 $39.55 Granted — — Vested — — Forfeited (2) $39.55 Nonvested at December 31, 2022 8 $39.55 Granted — — Vested — — Forfeited — — Nonvested at December 31, 2023 8 $39.55 Restricted Stock (Performance Condition) - 2022 Award A summary of restricted stock with performance-based vesting granted under the 2014 Plan for the year ended December 31, 2023, are as follows: Shares Weighted Average Grant Date Fair Value (per share) Nonvested at December 31, 2021 — — Granted 24 $33.70 Vested — — Forfeited (2) $33.70 Nonvested at December 31, 2022 22 $33.70 Granted — — Vested — — Forfeited (5) $33.70 Nonvested at December 31, 2023 17 $33.70 Restricted Stock (Performance Condition) - 2023 Award A summary of restricted stock with performance-based vesting granted under the 2014 Plan for the year ended December 31, 2023, are as follows: Shares Weighted Average Grant Date Fair Value (per share) Nonvested at December 31, 2022 — — Granted 17 $42.70 Vested — — Forfeited (6) $42.70 Nonvested at December 31, 2023 11 $42.70

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2023
Income Tax Disclosure [Abstract]
Income Taxes	INCOME TAXES Income Tax Expense (Benefit) The income tax expense (benefit) is as follows (in millions): Year Ended December 31, 2023 2022 2021 Current: Federal $ — $ — $ — State and local 1.6 1.0 0.4 Foreign — — — 1.6 1.0 0.4 Deferred: Federal (a) (0.7) 14.9 (40.7) State and local (0.8) (0.3) 1.2 Foreign — — — (1.5) 14.6 (39.5) Income tax expense (benefit) $ 0.1 $ 15.6 $ (39.1) (a) The income tax expense for 2023 and the income tax benefit for 2021 include the reversal of a portion of the federal valuation allowance on net deferred tax assets. See further discussion below. Deferred Taxes Future tax consequences of temporary differences between the carrying amounts for financial reporting purposes and the Company’s estimate of the tax bases of its assets and liabilities result in deferred tax assets and liabilities, as follows (in millions): December 31, 2023 2022 Deferred tax assets: Employee benefits costs $ 27.1 $ 33.5 Inventory 31.3 21.3 Property, plant and equipment 178.0 190.2 Research and experimental expenditures 3.3 3.5 Net operating loss and credit carryforwards 172.0 188.6 Accrued expenses 0.4 4.9 Long-term debt and financing costs 5.5 7.6 Lease liability 0.8 2.1 Other 0.6 0.4 Deferred tax assets 419.0 452.1 Valuation allowance (382.4) (414.1) Deferred tax assets, net of valuation allowance $ 36.6 $ 38.0 Deferred tax liabilities: Intangible assets $ 7.1 $ 9.0 Lease asset 0.6 1.8 Prepaid expenses 0.4 0.4 Deferred tax liabilities $ 8.1 $ 11.2 Deferred tax assets, net $ 28.5 $ 26.8 The valuation allowance reduces the net deferred tax assets to their net realizable value. The ultimate realization of the net deferred tax assets is dependent upon generating sufficient taxable income in future years when deferred tax assets are recoverable or are expected to reverse. The Company evaluated both positive and negative evidence that was objectively verifiable to determine the amount of the federal valuation allowance that was required on Centrus’ federal deferred tax assets. Centrus has visibility on a significant portion of revenue in the LEU segment for 2023 through 2026, primarily from its long-term sales contracts. Centrus determined that the positive evidence of increased forecasted future income in the LEU segment based on existing sales Order Book and supply contracts along with commodity market forward pricing indicators, supported the release of the federal valuation allowance. However, due to lack of objectively verifiable information in later years, it was determined that forecasted future income was not sufficient to realize all the deferred tax assets. Therefore, Centrus recorded a partial release of its federal valuation allowance. In the third and fourth quarters of 2023, respectively, Centrus released ($7.7) million and ($11.7) million of the valuation allowance against its federal net deferred tax assets. The Company continues to maintain a partial valuation allowance against its remaining federal and state net deferred tax assets due to significant federal and state net operating losses and insufficient future taxable income. As of December 31, 2023, the valuation allowance against the remaining federal and state net deferred tax assets was $382.4 million. In 2022, an analysis of the positive and negative evidence was performed to determine if a change to the federal valuation allowance was required. Centrus evaluated both positive and negative evidence that was objectively verifiable to determine the amount of the valuation allowance that was required on Centrus’ deferred tax assets. Centrus had visibility on a significant portion of revenue in the LEU segment for the next few years, primarily from its long-term sales contracts. Centrus considered both its achievement of sustained profitability and cumulative income in 2022, as well as the forecasted income to be significant forms of positive evidence. Negative evidence included uncertainty in and the lack of objectively verifiable evidence for profitability in later years in Centrus’ LEU segment when existing Order Book and supply contracts expire and in Centrus’ Technical Solutions segment related to future funding of the HALEU enrichment facility. Based on the analysis, positive evidence continued to outweigh negative evidence. However, it was determined that no further change to the federal valuation allowance was necessary in 2022, and the Company continued to maintain a partial valuation allowance against its remaining federal and state net deferred tax assets due to significant federal and state net operating losses and insufficient future taxable income. As of December 31, 2022, the valuation allowance against the remaining federal and state net deferred tax assets was $414.1 million. Going forward, Centrus will continue to evaluate both positive and negative evidence that would support any further changes to the remaining federal and state valuation allowances. Such evidence in the Company’s Technical Solutions segment may include events that could have a significant impact on pre-tax income, such as signing new contracts with significantly higher or lower margins than currently forecasted, follow-on work related to the HALEU program, or abandonment of the commercial deployment of the centrifuge technology. Such evidence in our LEU segment may include renewing SWU sales contracts with existing customers and/or signing new SWU sales or purchase contracts with significantly higher or lower margins than currently forecasted. Additional evidence in the LEU segment may include potential deferrals in the timing of deliveries requested by its customers, which could impact revenue recognition timing. The impact of these and other potential positive and negative events will be weighed and evaluated to determine if the valuation allowances should be increased or decreased in the future. The Company has federal NOLs of $568.0 million generated through December 31, 2017, that currently expire through 2037. In addition, the Company has federal NOL carryforwards of $131.4 million generated after December 31, 2017, that do not expire. Centrus also has state NOL carryforwards of $488.4 million, with a full valuation allowance, that currently expire through 2038. Effective Tax Rate A reconciliation of income taxes calculated based on the federal statutory income tax rate and the effective tax rate follows: Year Ended December 31, 2023 2022 2021 Federal statutory tax rate 21 % 21 % 21 % Valuation allowance against net deferred tax assets (38) (1) (53) State rate changes 15 2 1 Executive compensation 1 1 1 State income tax expense, net of federal benefit — (1) 1 Uncertain tax positions 1 1 — Effective tax rate — % 23 % (29) % The effective tax rate for the year ended December 31, 2023, includes a decrease to the valuation allowance against net deferred tax assets of $31.7 million, or a change to the effective tax rate of (38%). Included in the valuation allowance decrease is the release of the valuation allowance against federal net deferred taxes of $19.4 million, or a change to the effective tax rate of (23%), as well as a release of the valuation allowance against state net deferred taxes for state rate changes of $12.3 million during the year, as a result of state law changes, or a change to the effective tax rate of (15%). There is an offsetting increase to the effective tax rate for state rate changes of $12.1 million, or a change to the effective tax rate of 15% so that the impact for the state rate changes net of the corresponding valuation allowance decrease is zero. The effective tax rate for the year ended December 31, 2022, includes a decrease to the valuation allowance against state net deferred tax assets of $0.6 million, or a change to the effective tax rate of (1%). The effective tax rate for the year ended December 31, 2021, includes a decrease to the valuation allowance against net deferred tax assets of $71.3 million, or a change to the effective tax rate of (53%). Included in the valuation allowance decrease is the release of the valuation allowance against federal net deferred taxes of $40.7 million, or a change to the effective tax rate of (30%). Uncertain Tax Positions Accounting standards require that a tax position meet a minimum recognition threshold in order for the related tax benefit to be recognized in the financial statements. The liability for unrecognized tax benefits, included in Other Long-Term Liabilities , was $2.9 million as of December 31, 2023, and $1.9 million as of December 31, 2022. If recognized, these tax benefits would impact the effective tax rate. As a result of changes to unrecognized tax benefits, the income tax provision (state tax, net of federal benefit) increased by $1.0 million and $0.9 million during the year ended December 31, 2023 and 2022, respectively. The liability for unrecognized tax benefits in the table below relates to unrecognized state income tax benefits. Centrus believes that the liability for unrecognized tax benefits will not change significantly in the next 12 months. A reconciliation of the beginning and ending amount of unrecognized tax benefits follows (in millions): Year Ended December 31, 2023 2022 Balance at beginning of the period $ 1.9 $ 1.0 Additions to tax positions of current period 1.0 0.9 Reductions to tax positions of prior years — — Balance at end of the period $ 2.9 $ 1.9 Centrus and its subsidiaries file income tax returns with the U.S. government and various states and foreign jurisdictions. As of December 31, 2023, the federal, Maryland and Tennessee statutes of limitation are closed with respect to all tax years through 2019. Centrus recognizes accrued interest related to uncertain tax positions as a component of Interest Expense . Reversals of previously accrued interest for income taxes is typically offset against interest expense, but if the amount is significant, it is reclassified to interest income in the Consolidated Statements of Operations. Centrus recognizes the increase or decrease of accrued penalties for income taxes as a component of S elling, General and Administrative in the Consolidated Statements of Operations. The impact of accrued interest and penalties for income taxes in the Consolidated Statements of Operations was an increase to expenses of $0.2 million for the year ended December 31, 2023, and $0.1 million for the year ended December 31, 2022. Accrued interest and penalties for income taxes, included as a component of Other Long-Term Liabilities , totaled $0.3 million as of December 31, 2023, and $0.1 million as of December 31, 2022.

Net Income Per Share

Net Income Per Share	12 Months Ended
	Dec. 31, 2023
Earnings Per Share [Abstract]
Net Income (Loss) Per Share	NET INCOME PER COMMON SHARE Basic net income per share is calculated by dividing income allocable to common stockholders by the weighted average number of shares of common stock outstanding during the period. In calculating diluted net income per share, the number of shares is increased by the weighted average number of potential common shares related to stock compensation awards including restricted stock, stock options, stock appreciation rights and notional stock units, and the warrant. No dilutive effect is recognized in a period in which a net loss has occurred. On February 2, 2021, the Company completed the exchange of 3,873 shares of its outstanding Series B Senior Preferred Stock, par value $1.00 per share (“Preferred Stock”) for (i) 231,276 shares of Class A Common Stock and (ii) a warrant to purchase 250,000 shares of Class A Common Stock at an exercise price of $21.62 per share, for an aggregate valuation of approximately $7.5 million. The carrying value of the Series B Senior Preferred Stock on the Balance Sheet was $1.00 per share par value. The aggregate liquidation preference of the Series B Senior Preferred Stock, including accrued but unpaid dividends, was $1,291.04 per share as of December 31, 2020. On November 23, 2021, the Company completed the purchase of 36,867 shares of its outstanding Series B Senior Preferred Stock at a price per share of $1,145.20, less any applicable withholding taxes. The Company also completed the purchase of the remaining 980 shares of its outstanding Series B Senior Preferred Stock at a price per share of $1,149.99, less any applicable withholding taxes, on December 15, 2021 (Refer to Note 16, Stockholders’ Equity ). The aggregate purchase price of both transactions was $43.3 million. The carrying value of the Series B Senior Preferred Stock on the Consolidated Balance Sheet was $1.00 per share par value. The aggregate valuation of all 2021 preferred stock transactions of approximately $50.8 million, less accrued but unpaid dividends attributable to the acquired and retired shares of Series B Senior Preferred Stock, is considered for purposes of Net Income per Share to be a deemed dividend in the aggregate amount equal to the amount by which it exceeds the carrying value of the Preferred Stock on the Consolidated Balance Sheet, or $37.6 million. On December 29, 2022, the Company amended and restated the warrant issued on February 2, 2021, to extend the term to February 5, 2024. The change in the fair value of the warrant is considered as a reduction to net income available to common stockholders for purposes of Net Income per Share . On December 18, 2023, Kulayba LLC delivered a note of exercise with regard to all 250,000 shares issued under the warrant via a cashless exercise. The closing market price of a share of Class A Common Stock on the exercise date of the warrant was $53.61. Pursuant to the warrant, the exercise price was $21.62 per share. The cashless exercise resulted in the purchase of 149,179 Shares of Class A Common Stock by Kulayba LLC on December 18, 2023. For further detail, refer to Note 16, Stockholders’ Equity . The weighted average number of common and common equivalent shares and the calculation of basic and diluted income per common share are as follows: Year Ended December 31, 2023 2022 2021 Numerator (in millions): Net income $ 84.4 $ 52.2 $ 175.0 Warrant modification — 1.5 — Preferred stock dividends - undeclared and cumulative — — 2.1 Distributed earnings allocable to retired preferred shares — — 37.6 Net income allocable to common stockholders $ 84.4 $ 50.7 $ 135.3 Denominator (in thousands): Average common shares outstanding - basic 15,212 14,601 13,493 Potentially dilutive shares related to stock compensation awards and warrant 289 387 386 Average common shares outstanding - diluted 15,501 14,988 13,879 Net income per common share (in dollars): Basic $ 5.55 $ 3.47 $ 10.03 Diluted $ 5.44 $ 3.38 $ 9.75

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2023
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	COMMITMENTS AND CONTINGENCIES Commitments under SWU Purchase Agreements TENEX The Russian government-owned entity TENEX, is a major supplier of SWU to the Company. Under the 2011 TENEX Supply Contract, the Company purchases SWU contained in LEU received from TENEX, and the Company delivers natural uranium to TENEX for the LEU’s uranium component. The LEU that the Company obtains from TENEX is subject to quotas and other restrictions applicable to commercial Russian LEU. Further, the ability of the Company or TENEX to perform under the TENEX Supply Contract is vulnerable to (i) sanctions or restrictions that might be imposed by Russia, the United States, or other countries as a result of the war in Ukraine, or otherwise, (ii) customers and other parties who may object to receiving or handling Russian LEU or SWU, or (iii) suppliers and service providers seeking to limit their involvement with business related to Russia. The TENEX Supply Contract originally was signed with commitments through 2022, but was modified in 2015 to give the Company the right to reschedule certain quantities of SWU of the original commitments into the period 2023 and beyond, in return for the purchase of additional SWU in those years. The Company has exercised this right to reschedule in each year through December 31, 2023. As a result of exercising this right to reschedule, the Company will have purchase commitments that could extend through 2028. The TENEX Supply Contract provides that the Company must pay for all SWU in its minimum purchase obligation each year, even if it fails to submit orders for such SWU. In such a case, the Company would pay for the SWU, but have to take the unordered SWU in the following year. Pricing terms for SWU under the TENEX Supply Contract are based on a combination of market-related price points and other factors. This formula was subject to an adjustment at the end of 2018 that reduced the unit costs of SWU under this contract in 2019 and for the duration of the contract. Orano In 2018, the Company entered into the Orano Supply Agreement with the French company Orano Cycle for the long-term supply to the Company of SWU contained in LEU. The Orano Supply Agreement subsequently was assigned by Orano Cycle to its affiliate, Orano CE. Under the amended Orano Supply Agreement, the supply of SWU runs through 2030. The Orano Supply Agreement provides significant flexibility to adjust purchase volumes, subject to annual minimums and maximums in fixed amounts that vary year by year. The pricing for the SWU purchased by the Company is determined by a formula that uses a combination of market-related price points and other factors and is subject to certain floors and ceilings. Milestones Under the 2002 DOE-USEC Agreement The Company’s predecessor USEC Inc. and the DOE signed the 2002 DOE-USEC Agreement dated June 17, 2002, pursuant to which the parties made long-term commitments directed at resolving issues related to the stability and security of the domestic uranium enrichment industry. The 2002 DOE-USEC Agreement requires Centrus to develop, demonstrate and deploy advanced enrichment technology in accordance with milestones, including the deployment of a commercial American Centrifuge Plant, and provides for remedies in the event of a failure to meet a milestone under certain circumstances, including terminating the 2002 DOE-USEC Agreement, revoking Centrus’ access to the DOE’s centrifuge technology that is required for the success of the Company’s ongoing work with the American Centrifuge technology, requiring Centrus to transfer certain rights in the American Centrifuge technology and facilities to the DOE, and requiring Centrus to reimburse the DOE for certain costs associated with the American Centrifuge technology. The 2002 DOE-USEC Agreement provides that if a delaying event beyond the control and without the fault or negligence of Centrus occurs that could affect Centrus’ ability to meet the American Centrifuge Plant milestone under the 2002 DOE-USEC Agreement, the DOE and the Company will jointly meet to discuss in good faith possible adjustments to the milestones as appropriate to accommodate the delaying event. In 2014, the 2002 DOE-USEC Agreement and other agreements between the Company and the DOE were assumed by Centrus subject to an express reservation of all rights, remedies and defenses by the DOE and the Company under those agreements. The DOE and the Company have agreed that all rights, remedies and defenses of the parties with respect to any missed milestones and all other matters under the 2002 DOE-USEC Agreement continue to be preserved, and that the time limits for each party to respond to any missed milestones continue to be tolled. Legal Matters From time to time, the Company is involved in various pending legal proceedings, including the pending legal proceedings described below. In 1993, USEC-Government entered into a lease for the Paducah and Portsmouth GDPs with the DOE. As part of that lease, the DOE and USEC-Government also entered into a Power MOU regarding power purchase agreements between DOE and the providers of power to the GDPs. Under the Power MOU, the DOE and USEC-Government agreed upon the allocation of rights and liabilities under the power purchase agreements. In 1998, USEC-Government was privatized and became Enrichment Corp., now a principal subsidiary of the Company. Pursuant to legislation authorizing the privatization, the lease for the GDPs, which included the Power MOU as an Appendix, was transferred to Enrichment Corp. and Enrichment Corp. was given the right to purchase power from the DOE. The Paducah GDP was shut down in 2013 and deleased by Enrichment Corp. in 2014. On August 4, 2021, the DOE informally informed Enrichment Corp. that the Joppa power plant, which had supplied power to the Paducah GDP, was planned to be D&D. According to the DOE, the power purchase agreement with Electric Energy Inc. requires the DOE to pay for a portion of the D&D costs of the Joppa power plant and the DOE has asserted that a portion of the DOE liability is the responsibility of Enrichment Corp. under the Power MOU in the amount of approximately $9.6 million. The Company is assessing the DOE’s assertions including whether all or a portion of any such potential liability had been previously settled. The Company has not formed an opinion on the merits nor is it able to estimate the potential liability, if any, and no expense or liability has been accrued. On May 26, 2019, the Company, Enrichment Corp., and six other DOE contractors who have operated facilities at the Portsmouth GDP (including, in the case of the Company, the American Centrifuge Plant site located on the premises) were named as defendants in a class action complaint filed by Ursula McGlone, Jason McGlone, Julia Dunham, and K.D. and C.D., minor children by and through their parent and natural guardian Julia Dunham (collectively, the “McGlone Plaintiffs”) in the U.S. District Court in the Southern District of Ohio, Eastern Division. The complaint seeks damages for alleged off-site contamination allegedly resulting from activities on the Portsmouth GDP site. The McGlone Plaintiffs are seeking to represent a class of (i) all current or former residents within a seven-mile radius of the Portsmouth GDP site and (ii) all students and their parents at the Zahn’s Corner Middle School from 1993-present. The complaint was amended on December 10, 2019 and on January 10, 2020 to add additional plaintiffs and new claims. On July 31, 2020, the court granted in part and denied in part the defendants’ motion to dismiss the case. The court dismissed ten of the fifteen claims and allowed the remaining claims to proceed to the next stage of the litigation process. On August 18, 2020, the McGlone Plaintiffs filed a motion for leave to file a third amended complaint and notice of dismissal of three of the individual plaintiffs. On March 18, 2021, the McGlone Plaintiffs filed a motion for leave to file a fourth amended complaint to add new plaintiffs and allegations. On March 19, 2021, the court granted the McGlone Plaintiffs’ motion for leave to amend the complaint to include Price-Anderson Act and eight other state law claims. On May 24, 2021, the Company, Enrichment Corp., and the other defendants filed their motion to dismiss the complaint. On March 31, 2022, the court granted the Company’s motion in part by dismissing claims brought on behalf of the minor children but allowed the other claims to proceed. As such, the discovery stage of litigation is continuing. On April 28, 2022, the Company, Enrichment Corp., and the other defendants filed their answer to the fourth amended complaint. The Company believes that its operations at the Portsmouth GDP site were fully in compliance with the NRC’s regulations. Further, the Company and Enrichment Corp. believe that any such liability should be indemnified under the Price-Anderson Act. The Company and Enrichment Corp. have provided notifications to DOE required to invoke indemnification under the Price-Anderson Act and other contractual provisions. On June 8, 2022, the Company, Enrichment Corp., and six other DOE contractors who operated facilities at the Portsmouth GDP were named as defendants in a complaint filed by Brad Allen Lykins, as administrator of the estate of Braden Aaron Lee Lykins in the U.S. District Court in the Southern District of Ohio, Eastern Division (“Lykins Complaint”). In March 2021, Brayden Lykins, who was thirteen years old, passed away from leukemia. The complaint alleges that the defendants released radiation into the environment in violation of the Price-Anderson Act causing Lykins’ death and seeks monetary damages. On August 30, 2022, the Company, Enrichment Corp. and the other defendants filed their answer to the Lykins Compliant. The Company and Enrichment Corp. believe that their operations at the Portsmouth GDP site were fully in compliance with the NRC’s regulations. Further, the Company and Enrichment Corp. believe that any such liability should be indemnified under the Price-Anderson Act. The Company and Enrichment Corp. have provided notifications to the DOE required to invoke indemnification under the Price-Anderson Act and other contractual provisions. On March 8, 2023, the Company, Enrichment Corp., and six other DOE contractors that operated facilities at the Portsmouth GDP were named as defendants in a complaint filed by Christian Rose in the U.S. District Court in the Southern District of Ohio, Eastern Division (“Rose Complaint”). Christian Rose was diagnosed with cancer in June 2022. Although Mr. Rose is an adult, he attended the Zahn Corner Middle School, which was closed a few years ago due to contamination and is in the vicinity of the plant. The Rose Complaint alleges that the defendants released radiation into the environment in violation of the Price-Anderson Act causing death – even though the plaintiff is still alive – and seeks monetary damages in nature of past and future medical expenses, pain and suffering and punitive damages, among others. On May 15, 2023, the Company, Enrichment Corp. and the other defendants filed their answers to the Rose Complaint. The Company and Enrichment Corp. believe that their operations at the Portsmouth GDP site were fully in compliance with the NRC’s regulations. Further, the Company and Enrichment Corp. believe that any such liability should be indemnified under the Price-Anderson Act. The Company and Enrichment Corp. have provided notifications to the DOE required to invoke indemnification under the Price-Anderson Act and other contractual provisions. On November 27, 2023, the Company, Enrichment Corp. and six other DOE contractors who operated facilities at the Portsmouth GDP were named as defendants in a complaint filed by Joshua Shaw in the U.S. District Court in the Southern District of Ohio, Eastern Division (“Shaw Complaint”). Joshua Shaw was diagnosed with Acute Myeloid Leukemia (AML) in August 2008 and after going through chemotherapy continues to suffer from aftereffects of AML, including anxiety and fatigue. The Shaw Complaint alleges that the defendants released radiation into the environment exposing Mr. Shaw to radiation in violation of the Price-Anderson Act and causing Mr. Shaw’s AML and other injuries. Mr. Shaw seeks monetary damages in nature of past and future medical expenses for treatment and care, pain and suffering and punitive damages, among others. The Company and Enrichment Corp. believe that their operations at the Portsmouth GDP site were fully in compliance with the NRC’s regulations. Further, the Company and Enrichment Corp. believe that any such liability should be indemnified under the Price-Anderson Act. The Company and Enrichment Corp. have provided notifications to the DOE required to invoke indemnification under the Price-Anderson Act and other contractual provisions. Centrus is subject to various legal proceedings and claims, either asserted or unasserted, which arise in the ordinary course of business. While the outcome of these claims cannot be predicted with certainty, other than the above, Centrus does not believe that the outcome of any of these legal matters, individually and in the aggregate, will have a material adverse effect on its cash flows, results of operations or financial condition.

Accumulated Other Comprehensive

Accumulated Other Comprehensive Income (Loss)	12 Months Ended
	Dec. 31, 2023
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
Accumulated Other Comprehensive Income (Loss)	ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) The sole component of accumulated other comprehensive income (loss) relates to activity in the accounting for pension and postretirement health and life benefit plans. The amortization of prior service costs (credits) is reclassified from accumulated other comprehensive income (loss) and included in the computation of net periodic benefit cost. For further details, refer to Note 11, Pension and Postretirement Health and Life Benefits

Segment Information

Segment Information	12 Months Ended
	Dec. 31, 2023
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Segment Information	REVENUE BY GEOGRAPHIC AREA, MAJOR CUSTOMERS AND SEGMENT INFORMATION Revenue by customer location, including customers in a foreign country representing 10% or more of total revenue, follows (in millions): Year Ended December 31, 2023 2022 2021 United States $ 281.6 $ 154.3 $ 220.5 Foreign: Belgium 0.1 38.3 36.6 Japan 23.6 61.6 34.6 Other 14.9 39.6 6.6 Total foreign 38.6 139.5 77.8 Total revenue $ 320.2 $ 293.8 $ 298.3 The U.S. government and its contractors, in the Company’s Technical Solutions segment, represented approximately 16% of total revenue for the year ended December 31, 2023, 20% for the year ended December 31, 2022, and 38% for the year ended December 31, 2021. The ten largest customers in the Company’s LEU segment represented approximately 79% of total revenue for the year ended December 31, 2023. Revenue from Customer A , Customer B, and Customer C represented approximately 17%, 15%, and 13% respectively, of total revenue for the year ended December 31, 2023. The ten largest customers in the Company’s LEU segment represented approximately 75% of total revenue for the year ended December 31, 2022. Revenue from Kyushu Electric Power Company and Synatom represented approximately 15% and 13%, respectively, of total revenue for the year ended December 31, 2022. The ten largest customers in the Company’s LEU segment represented approximately 57% of total revenue for the year ended December 31, 2021. Revenue from Kyushu Electric Power Company and Synatom represented approximately 12% of total revenue for the year ended December 31, 2021. No other customer represented more than 10% of total revenue for the year ended December 31, 2023, 2022, or 2021. Centrus has two reportable segments: the LEU segment with two components, SWU and uranium, and the Technical Solutions segment. The LEU segment includes sales of the SWU component of LEU, sales of both the SWU and uranium components of LEU, and sales of uranium. The Technical Solutions segment includes revenue and cost of sales for work that Centrus performs under the HALEU Demonstration and Operation Contracts. The Technical Solutions segment also includes limited services provided by Centrus to DOE and its contractors at the Piketon facility. Gross profit is Centrus’ measure for segment reporting. Net sales of the Company’s business segments in the following tables exclude intersegment sales as these activities are eliminated in consolidation and thus are not included in management’s evaluation of performance of each segment. Sales between segments are recorded at market prices at the time of the sale. Such intercompany operating income is eliminated in consolidation, so that the company’s total sales and total operating income reflect only those transactions with external customers. Refer to Note 1, Summary of Significant Accounting Policies , and Note 2 , Revenue and Contracts with Customers, for additional details on revenue for each segment. The following table presents the Company’s segment information (in millions): Year Ended December 31, 2023 2022 2021 Revenue LEU segment: Separative work units $ 208.2 $ 196.2 $ 163.3 Uranium 60.8 39.4 22.8 Intersegment revenue, eliminated on consolidation 5.0 — — Total 274.0 235.6 186.1 Technical Solutions segment 51.2 58.2 112.2 Total revenue 325.2 293.8 298.3 Elimination of intersegment revenue (5.0) — — Total revenue $ 320.2 $ 293.8 $ 298.3 Segment Gross Profit (Loss) LEU segment: LEU segment $ 105.1 $ 130.6 $ 73.0 Intersegment gross profit, eliminated on consolidation 2.0 — — Total 107.1 130.6 73.0 Technical Solutions segment: Technical Solutions segment 7.0 (12.7) 41.5 Intersegment gross profit, eliminated on consolidation 3.0 Total 10.0 (12.7) 41.5 Elimination of intersegment gross profit (5.0) — — Gross profit $ 112.1 $ 117.9 $ 114.5 The Company’s total assets are not presented for each reportable segment as they are not reviewed by, nor otherwise regularly provided to the chief operating decision maker. Centrus’ long-term or long-lived assets, which include property, plant and equipment and other assets reported on the Consolidated Balance Sheet, were located in the United States as of December 31, 2023, and December 31, 2022.

Pay vs Performance Disclosure

Pay vs Performance Disclosure - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Pay vs Performance Disclosure
Net income	$ 84.4	$ 52.2	$ 175

Insider Trading Arrangements

Insider Trading Arrangements	3 Months Ended
	Dec. 31, 2023
Trading Arrangements, by Individual
Rule 10b5-1 Arrangement Adopted	false
Non-Rule 10b5-1 Arrangement Adopted	false
Rule 10b5-1 Arrangement Terminated	false
Non-Rule 10b5-1 Arrangement Terminated	false

Summary of Significant Accounti

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2023
Summary of Significant Accounting Policies [Abstract]
Basis of Accounting, Policy [Policy Text Block]	Basis of Presentation and Principles of Consolidation The Consolidated Financial Statements of Centrus Energy Corp. (“Centrus” or the “Company”), which include the accounts of the Company, its principal subsidiary Enrichment Corp., and its other subsidiaries, were prepared in conformity with U.S. GAAP. Certain prior year amounts have been reclassified for consistency with the current year presentation. All material intercompany transactions have been eliminated.
Use of Estimates, Policy [Policy Text Block]	Use of Estimates The preparation of Consolidated Financial Statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect reported amounts presented and disclosed in the Consolidated Financial Statements. Significant estimates and judgments include, but are not limited to, revenue and related costs, asset valuations, pension and postretirement health and life benefit costs and obligations, the tax bases of assets and liabilities, the future recoverability of deferred tax assets, and determination of the valuation allowance for deferred tax assets. Actual results may differ from such estimates, and estimates may change if the underlying conditions or assumptions change.
Cash and Cash Equivalents, Policy [Policy Text Block]	Cash and Cash Equivalents Cash and cash equivalents include short-term or highly liquid assets with original maturities of three months or less.
Inventory, Policy [Policy Text Block]	Inventories and Inventories Owed to Customers and Suppliers LEU consists of two components: SWU and UF 6 . SWU is a standard unit of measurement that represents the effort required to transform a given amount of natural uranium into two components: enriched uranium having a higher percentage of U 235 and depleted uranium having a lower percentage of U 235 . The SWU contained in LEU is calculated using an industry standard formula based on the physics of enrichment. The amount of enrichment deemed to be contained in LEU under this formula is commonly referred to as its SWU component and the quantity of natural uranium hexafluoride deemed to be used in the production of LEU under this formula is referred to as its uranium or “feed” component. SWU and uranium inventory costs are determined using the average cost method. SWU and uranium purchase costs include shipping costs when applicable. Inventories of SWU and uranium are valued at the lower of cost or NRV. NRV is the estimated selling price in the ordinary course of business less reasonably predictable costs of completion, disposal, and transportation. The estimated selling price for SWU and uranium is based on the pricing terms of contracts in the Company’s Order Book, and, for uranium not under contract, the estimated selling price is based primarily on published price indicators at the balance sheet date. Inventories owed to customers and suppliers, included in current liabilities, consist primarily of SWU and uranium inventories owed to fabricators. Fabricators process LEU into fuel for use in nuclear reactors. Under inventory optimization arrangements between Centrus and domestic fabricators, fabricators order quantities of LEU from Centrus based on scheduled or anticipated orders from utility customers, for deliveries in future periods. As delivery obligations under actual customer orders arise, Centrus typically satisfies these obligations by arranging for the transfer to the customer of title to the specified quantity of LEU at the fabricator. Centrus’ balances of SWU and uranium vary over time based on the timing and size of the fabricator’s LEU orders from Centrus and the fabricator’s needs for working stock of LEU. Balances can be positive or negative at the discretion of the fabricator. Fabricators have other inventory supplies and, where a fabricator has elected to order less material from Centrus than Centrus is required to deliver to its customers at the fabricator, the fabricator will use these other inventories to satisfy Centrus’ customer order obligations on Centrus’ behalf. In such cases, the transfer of title of LEU from Centrus to the customer results in quantities of SWU and uranium being owed by Centrus to the fabricator. The amounts of SWU and uranium owed to fabricators are satisfied as future deliveries of LEU to fabricators are made.
Income Tax, Policy [Policy Text Block]	Deferred Taxes Centrus follows the asset and liability approach to account for deferred taxes. Deferred tax assets and liabilities are recognized for the anticipated future tax consequences of temporary differences between the balance sheet carrying amounts of assets and liabilities and their respective tax bases. Deferred taxes are based on income tax rates in effect for the years in which temporary differences are expected to reverse. The effect on deferred taxes of a change in income tax rates is recognized in income when the change in rates is enacted in the law. A valuation allowance is provided if it is more likely than not that all, or some portion, of the deferred tax assets may not be realized.
Property, Plant and Equipment, Policy [Policy Text Block]	Property, Plant and Equipment Property, plant and equipment are recorded at acquisition cost. Leasehold improvements and machinery and equipment are depreciated on a straight-line basis over the shorter of the useful life of the assets or the lease term, if applicable. Refer also to Carrying Value of Long-Lived Assets below.
Intangible Assets, Policy [Policy Text Block]	Intangible Assets Centrus has intangible assets resulting from fresh start accounting as a result of emergence from Chapter 11 bankruptcy on September 30, 2014. The identifiable intangible assets relate to the sales Order Book and customer relationships. The Order Book intangible asset is amortized as the Order Book valued at emergence is reduced, principally as a result of deliveries to customers. The customer relationships intangible asset is amortized using the straight-line method over the estimated average useful life of 15 years, with 5 ¾ years of scheduled amortization remaining. Refer also to Carrying Value of Long-Lived Assets below. Carrying Value of Long-Lived Assets The Company evaluates the carrying values of property, plant and equipment and identifiable intangible assets when events or changes in business circumstances indicate that the carrying amount of asset, or asset group, may not be fully recoverable. The carrying amount of a long-lived asset is not recoverable if it exceeds the sum of the undiscounted cash flows expected to result from the use and eventual disposition of the asset. An impairment loss is measured as the amount by which the carrying amount of a long-lived asset, or asset group, exceeds its fair value.
Fair Value of Financial Instruments, Policy [Policy Text Block]	Financial Instruments and Fair Value Measurement Accounting standards define fair value as the price that would be received from selling an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. When determining the fair value measurements for assets and liabilities required or permitted to be recorded at fair value, consideration is given to the principal or most advantageous market and assumptions that market participants would use when pricing the asset or liability. Pursuant to accounting standards, Centrus’ 8.25% Notes due February 2027 are recorded at face value and the fair value is disclosed. The estimated fair value of the 8.25% Notes is based on bid/ask quotes as of or near the balance sheet date. Debt issuance costs are deferred and amortized over the life of the instrument. The balance sheet carrying amounts for accounts receivable, accounts payable and accrued liabilities, and payables under inventory purchase agreements approximate fair value because of the short-term nature of the instruments.
Concentration Risk, Credit Risk, Policy [Policy Text Block]	Concentrations of Credit Risk Credit risk could result from the possibility of a customer failing to perform or pay according to the terms of a contract. Extension of credit is based on an evaluation of each customer’s financial condition. Centrus regularly monitors credit risk exposure and takes steps intended to mitigate the likelihood of such exposure resulting in a loss.
Segment Reporting, Policy [Policy Text Block]	Segments
Revenue Recognition, Policy	Revenue The Company accounts for a contract when it has approval and commitment from both parties, the rights of the parties are identified, payment terms are identified, the contract has commercial substance and collectability of consideration is probable. Revenue for product and service sales is recognized when or as the Company transfers control of the promised products or services to the customer. Revenue is measured at the transaction price, which is based on the amount of consideration that the Company expects to receive in exchange for transferring the promised goods or services to the customer. The transaction price will include estimates of variable consideration until it is probable that a significant reversal of revenue recognized will not occur. SWU and Uranium Revenue Revenue for the Company’s LEU segment is derived from sales of the SWU component of LEU, from sales of both the SWU and uranium components of LEU, and from sales of UF 6 and U 3 0 8 . Contracts with customers are primarily medium and long-term, fixed-commitment, contracts under which its customers are obligated to purchase a specified quantity of the SWU component of LEU or the SWU and uranium components of LEU. The Company’s contracts for UF 6 and U 3 0 8 are generally shorter-term, fixed-commitment contracts. Revenue is recognized at the time the customer obtains control of the LEU or uranium. Customers generally obtain control of LEU at nuclear fuel fabricators. Centrus ships LEU to nuclear fuel fabricators for scheduled or anticipated orders from utility customers. Based on customer orders, Centrus arranges for the transfer of title of LEU from Centrus to the customer for the specified quantity of LEU at the fuel fabricator. Each such delivery to a customer is accounted for as a distinct performance obligation under a contract, and a contract may call for multiple deliveries over a number of periods. The contract’s transaction price is allocated to each performance obligation based on the observable standalone selling price of each distinct delivery of SWU or uranium. For certain contracts the customers may elect not to take control of the LEU or uranium and Centrus may have the right to enforce payment under the terms of the contractual agreement. The revenue recognition for these contracts is assessed when it occurs. Utility customers in general have the option to defer receipt of uranium products purchased from the Company beyond the contractual sale period. In such cases, title to SWU and/or uranium components are transferred to the customer and a performance obligation for Centrus is created and a receivable is recorded. Cash is collected for the receivable under normal credit terms. The performance obligation is represented as deferred revenue in Deferred Revenue and Advances from Customers on the Consolidated Balance Sheet and the customer-titled product is classified as Deferred Costs Associated with Deferred Revenue on the Consolidated Balance Sheet. Risk of loss remains with Centrus until the customer obtains control of the uranium product. The recognition of revenue and related cost of sales occurs at the point in time at which the customer obtains control of SWU or uranium and risk of loss of the product transfers to the customer, which may occur beyond one year. The timing of the transfer of control, subject to notice period requirements, is at the option of the customer. As such, deferred costs and deferred revenue are classified within current assets and current liabilities, respectively. On occasion, the Company will accept payment in the form of uranium. Revenue from the sale of SWU under such contracts is recognized at the time transfer of control of LEU occurs and is based on the fair value of the uranium at contract inception or, as the quantity of uranium is finalized, if variable. Amounts billed to customers for handling costs are included in sales. Handling costs are accounted for as a fulfillment cost and are included in cost of sales. The Company does not have shipping costs associated with outbound freight after control over a product has transferred to a customer. The Company’s contracts with customers do not provide for significant payment terms or financing components. Technical Solutions Revenue Revenue for the Technical Solutions segment, principally representing technical, manufacturing, engineering, procurement, construction and operations services offered to public and private sector customers, is recognized over the contractual period as services are rendered. The Company recognizes revenue over time as it performs on these contracts because of the continuous transfer of control to the customer. For public sector contracts, this continuous transfer of control to the customer is supported by clauses in the contract that allow the customer to unilaterally terminate the contract for convenience, pay the Company for costs incurred plus a reasonable profit and assume control of any work in progress. The Company’s government and private sector contracts generally contain contractual termination clauses or entitle the Company to payments for work performed to date for goods and services that do not have an alternative use. With control transferring over time, revenue is recognized based on the extent of progress towards completion of the performance obligation. A contract may contain one or more performance obligations. Two or more promises to transfer goods or services to a customer may be considered a single performance obligation if the goods or services are highly interdependent or highly interrelated such that utility of the promised goods or services to the customer includes integration services provided by the Company. The Company determines the transaction price for each contract based on the consideration it expects to receive for the products or services being provided under the contract. If transaction prices are not stated in the contract for each performance obligation, contractual prices are allocated to performance obligations based on estimated relative standalone selling prices of the promised services. For contracts with multiple performance obligations, the Company allocates the transaction price to each performance obligation based on the estimated standalone selling price of the product or service underlying each performance obligation. The standalone selling price represents the amount the Company would sell the product or service to a customer on a standalone basis (i.e., not bundled with any other products or services). The Company's contracts with the U.S. government are subject to the FAR and the price is typically based on estimated or actual costs plus a reasonable profit margin. As a result of these regulations, the standalone selling price of products or services in the Company’s contracts with the U.S. government are typically equal to the selling price stated in the contract. The Company does not contemplate future modifications, including unexercised options until they become legally enforceable. Contracts may be subsequently modified to include changes in specifications, requirements or price, which may create new or change existing enforceable rights and obligations. Depending on the nature of the modification, the Company considers whether to account for the modification as an adjustment to the existing contract or as a separate contract. The Company generally uses the cost-to-cost input method of progress for performance obligations to deliver products with continual transfer of control to the customer because it best depicts the transfer of control to the customer that occurs as the Company incurs costs. Under the cost-to-cost method, the extent of progress towards completion is measured based on the proportion of direct costs incurred to date to the total estimated direct costs at completion of the performance obligation. Revenues are recorded proportionally as costs are incurred. For performance obligations to provide services to the customer, revenue is recognized over time based on direct costs incurred or the right to invoice method (in situations where the value transferred matches the Company’s billing rights) as the customer receives and consumes the benefits. Use of the cost-to-cost method requires the Company to make reasonably dependable estimates of costs at completion associated with the design, manufacture and delivery of products and services in order to calculate revenue. Significant judgment is used to estimate total revenue and costs at completion, particularly in the assumptions related to internal labor hours and third-party services for which a vendor invoice or quote is not yet available. As a significant change in one or more estimates could affect the profitability of the Company’s contracts, the Company reviews and updates its contract-related estimates regularly. Adjustments in estimated profits/losses are recognized under the cumulative catch-up method. Under this method, the impact of the adjustments is recognized in the period the adjustment is recognized. When estimates of total costs at completion for such an integrated, construction type contract exceed total estimates of revenue to be earned on a performance obligation related to complex equipment or related services, a provision for the remaining loss on the performance obligation is recognized in the period the loss is determined. The Company applied the practical expedient in paragraph ASC 606-10-50-14 and does not disclose the value of remaining performance obligations under service contracts having original expected terms of one year or less. The timing of revenue recognition may differ from the timing of invoicing to customers. Progress on satisfying performance obligations under contracts with customers and the related billings and cash collections are recorded on the Consolidated Balance Sheet as contract assets or contract liabilities. Contract balances are classified as assets or liabilities on a contract-by-contract basis at the end of each reporting period. Unbilled receivables are included in Accounts Receivable on the Consolidated Balance Sheet and arise when the timing of cash collected from customers differs from the timing of revenue recognition. Those assets are recognized when the revenue associated with the contract is recognized prior to billing and derecognized when billed in accordance with the terms of the contract. To the extent billings to the customer precede the recognition of Technical Solutions revenue, the Company recognizes a liability included in Deferred Revenue and Advances from Customers
Advanced Technology Costs, Policy [Policy Text Block]	Advanced Technology Costs American Centrifuge and related expenses that are outside of the Company’s customer contracts are included in Advanced Technology Costs
Pension and Other Postretirement Plans, Policy [Policy Text Block]	Pension and Postretirement Health and Life Benefit Plans The Company provides retirement benefits to certain employees and retirees under defined benefit pension plans and postretirement health and life benefit plans. The valuation of benefit obligations and costs is based on provisions of the plans and actuarial assumptions that involve judgments and estimates. Plan assets and benefit obligations are remeasured each year as of the balance sheet date, or when lump sum payments exceed certain levels, resulting in differences between actual and projected results. The Company has elected to recognize these actuarial gains and losses immediately in the statement of operations to provide transparency regarding the impacts of changes in plan assets and benefit obligations. Executive Severance Plan The Company provides severance benefits to certain covered executives, which may also include continuation of certain insurance benefits, under an Executive Severance Plan (the “Severance Plan”). The benefits payable under the Severance Plan are based on salary level, amongst other variables. As the severance expenses are part of an on-going benefit arrangement, the Company recognizes the expense when payment of the severance is probable and can be reasonably estimated in accordance with ASC 712, Compensation — Nonretirement Postemployment Benefits .
Stock-based Compensation, Policy [Policy Text Block]	Stock-Based Compensation Centrus has a stock-based compensation plan which authorizes the issuance of common stock to the Company’s employees, officers, directors, and other individuals providing services to the Company or its affiliates pursuant to options, notional stock units, stock appreciation rights, restricted stock units, restricted stock, performance awards, dividend equivalent rights, and other stock-based awards. Stock-based compensation cost for options and stock-settled awards are measured at the grant date based on the fair value of the award. The cost is recognized over the requisite service period on a straight-line basis over the vesting period. Stock-based compensation cost for awards likely to be settled with cash payments is recognized over the requisite service period and accrued as a liability and re-measured each reporting period based on the trading price of the Company’s common stock. The Company recognizes forfeitures as they occur. New Accounting Standards Accounting Standards Effective in Future Periods In November 2023, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update ("ASU") 2023-07, Segment Reporting , to improve reportable segment disclosure requirements, primarily through enhanced disclosures about significant segment expenses. This pronouncement is effective for fiscal years beginning after December 15, 2023, and interim periods within fiscal years beginning after December 15, 2024 and early adoption is permitted. The Company is evaluating the impact this will have on its Consolidated Financial Statements. In December 2023, the FASB issued ASU 2023-09, Income Taxes , to improve the transparency of income tax disclosures, primarily through requiring consistent categories and greater disaggregation in the rate reconciliation and requiring disaggregation of income taxes paid by jurisdiction. This pronouncement is effective for fiscal years beginning after December 15, 2024 and early adoption is permitted. Based on the Company’s review, it does not expect the pronouncement to have any material impact on its Consolidated Financial Statements.

Revenue and Contracts with Cust

Revenue and Contracts with Customers (Tables)	12 Months Ended
	Dec. 31, 2023
Revenue from Contract with Customer [Abstract]
Revenue from External Customers by Geographic Areas	The following table presents revenue from SWU and uranium sales disaggregated by geographical region, including foreign countries representing 10% or more of revenue, based on the billing addresses of customers (in millions): Year Ended December 31, 2023 2022 2021 United States $ 230.4 $ 96.1 $ 108.3 Foreign: Belgium 0.1 38.3 36.6 Japan 23.6 61.6 34.6 Other 14.9 39.6 6.6 Total foreign 38.6 139.5 77.8 Revenue - SWU and uranium $ 269.0 $ 235.6 $ 186.1 Revenue by customer location, including customers in a foreign country representing 10% or more of total revenue, follows (in millions): Year Ended December 31, 2023 2022 2021 United States $ 281.6 $ 154.3 $ 220.5 Foreign: Belgium 0.1 38.3 36.6 Japan 23.6 61.6 34.6 Other 14.9 39.6 6.6 Total foreign 38.6 139.5 77.8 Total revenue $ 320.2 $ 293.8 $ 298.3
Contract with Customer, Asset and Liability	The following table presents changes in contract liability balances (in millions): December 31, 2023 2022 Change Accrued losses on HALEU Operation Contract: Current - Accounts payable and accrued liabilities $ — $ 20.0 $ (20.0) Deferred revenue - current $ 252.4 $ 258.4 $ (6.0) Advances from customers - current $ 30.2 $ 14.8 $ 15.4 Advances from customers - non current $ 32.8 $ 46.2 $ (13.4)

Cash, Cash Equivalents and Re_2

Cash, Cash Equivalents and Restricted Cash (Tables)	12 Months Ended
	Dec. 31, 2023
Cash, Cash Equivalents and Restricted Cash [Abstract]
Schedule of Cash and Cash Equivalents	The following table summarizes the Company’s cash, cash equivalents and restricted cash as presented on the Consolidated Balance Sheets to amounts on the Consolidated Statements of Cash Flows (in millions): December 31, 2023 2022 Cash and cash equivalents $ 201.2 $ 179.9 Deposits for financial assurance - current (a) 0.2 0.2 Deposits for financial assurance - non current 32.4 32.3 Total cash, cash equivalents and restricted cash $ 233.8 $ 212.4 (a) Deposits for financial assurance - current is included within Other Current Assets in the Consolidated Balance Sheets.
Schedule of Restricted Cash and Cash Equivalents	The following table provides additional detail regarding the Company’s deposits for financial assurance (in millions): December 31, 2023 December 31, 2022 Current Long-Term Current Long-Term Collateral for Inventory Loans $ — $ 29.8 $ — $ 29.8 Workers Compensation — 2.5 — 2.4 Other 0.2 0.1 0.2 0.1 Total deposits for financial assurance $ 0.2 $ 32.4 $ 0.2 $ 32.3

Inventories (Tables)

Inventories (Tables)	12 Months Ended
	Dec. 31, 2023
Inventory, Net [Abstract]
Schedule of Inventories	Components of inventories are as follows (in millions): December 31, 2023 December 31, 2022 Current Current Inventories, Net Current Current Inventories, Net Separative work units $ 21.9 $ — $ 21.9 $ 24.1 $ — $ 24.1 Uranium 284.5 84.3 200.2 185.1 60.8 124.3 Total $ 306.4 $ 84.3 $ 222.1 $ 209.2 $ 60.8 $ 148.4 (a)

Property, Plant and Equipment (

Property, Plant and Equipment (Tables)	12 Months Ended
	Dec. 31, 2023
Property, Plant and Equipment [Abstract]
Property, Plant and Equipment	A summary of changes in property, plant and equipment follows (in millions): December 31, Additions / (Depreciation) December 31, Land $ 1.2 $ — $ 1.2 Buildings and leasehold improvements 4.8 0.2 5.0 Machinery and equipment 2.0 1.8 3.8 Other 1.1 0.2 1.3 Property, plant and equipment, gross 9.1 2.2 11.3 Accumulated depreciation (3.6) (0.7) (4.3) Property, plant and equipment, net $ 5.5 $ 1.5 $ 7.0

Intangible Assets (Tables)

Intangible Assets (Tables)	12 Months Ended
	Dec. 31, 2023
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of Finite-Lived Intangible Assets [Table Text Block]	Intangible asset balances are as follows (in millions): December 31, 2023 December 31, 2022 Gross Carrying Amount Accumulated Amortization Net Amount Gross Carrying Amount Accumulated Amortization Net Amount Sales order book $ 54.6 $ 41.6 $ 13.0 $ 54.6 $ 39.9 $ 14.7 Customer relationships 68.9 42.5 26.4 68.9 37.9 31.0 Total $ 123.5 $ 84.1 $ 39.4 $ 123.5 $ 77.8 $ 45.7
Finite-lived Intangible Assets Amortization Expense [Table Text Block]	The amount of amortization expense for intangible assets in each of the succeeding years is estimated to be as follows (in millions): 2024 $ 8.9 2025 9.1 2026 7.4 2027 6.0 2028 4.6 Thereafter 3.4 Total $ 39.4

Accounts Payable and Accrued _2

Accounts Payable and Accrued Liabilities (Tables)	12 Months Ended
	Dec. 31, 2023
Accounts Payable and Accrued Liabilities [Abstract]
Schedule of Accounts Payable and Accrued Liabilities [Table Text Block]	Components of accounts payable and accrued liabilities follow (in millions): December 31, 2023 2022 Trade payables $ 6.1 $ 5.9 Compensation and employee benefits 21.1 15.7 Postretirement health and life benefit obligations - current 10.1 7.3 Accrued HALEU Operation Contract loss — 20.0 Short-term inventory loan 14.3 9.9 Operating lease liability 1.4 3.3 Other accrued liabilities 3.2 3.4 Total accounts payable and accrued liabilities $ 56.2 $ 65.5

Debt Schedule of Debt (Tables)

Debt Schedule of Debt (Tables)	12 Months Ended
	Dec. 31, 2023
Debt Disclosure [Abstract]
Schedule of Debt	A summary of debt follows (in millions): December 31, 2023 December 31, 2022 Maturity Current Long-Term Current Long-Term 8.25% Notes: Feb. 2027 Principal $ — $ 74.3 $ — $ 74.3 Interest 6.1 15.3 6.1 21.4 Total $ 6.1 $ 89.6 $ 6.1 $ 95.7

Leases (Tables)

Leases (Tables)	12 Months Ended
	Dec. 31, 2023
Leases [Abstract]
Lessee, Operating Lease, Liability, Maturity [Table Text Block]	The table below presents the lease-related assets and liabilities recorded on the Consolidated Balance Sheets (in millions). December 31, 2023 2022 Classification on the Balance Sheet Lease assets $ 2.7 $ 7.9 Other long-term assets Lease liabilities: Current $ 1.4 $ 3.3 Accounts payable and accrued liabilities Non current 2.6 6.1 Other long-term liabilities Total lease liabilities $ 4.0 $ 9.4 The table below reconciles undiscounted payments for operating leases with terms greater than 12 months to the operating lease liabilities recorded on the balance sheet as of December 31, 2023 (in millions). 2024 $ 1.9 2025 1.9 2026 1.0 2027 0.8 2028 — Thereafter — Total lease payments 5.6 Less imputed interest 1.6 Present value of lease payments $ 4.0

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	12 Months Ended
	Dec. 31, 2023
Fair Value Disclosures [Abstract]
Schedule of Financial Instruments Recorded at Fair Value	Financial Instruments Recorded at Fair Value (in millions): December 31, 2023 December 31, 2022 Level 1 Level 2 Level 3 Total Level 1 Level 2 Level 3 Total Assets: Cash and cash equivalents $ 201.2 $ — $ — $ 201.2 $ 179.9 $ — $ — $ 179.9 Deferred compensation asset (a) 3.3 — — 3.3 2.4 — — 2.4 Liabilities: Deferred compensation obligation (a) $ 3.3 $ — $ — $ 3.3 $ 2.4 $ — $ — $ 2.4

Pension and Postretirement He_2

Pension and Postretirement Health and Life Benefits (Tables)	12 Months Ended
	Dec. 31, 2023
Defined Benefit Plan Disclosure [Line Items]
Schedule of Changes in Projected Benefit Obligations [Table Text Block]	Changes in the projected benefit obligations and plan assets and the funded status of the plans follow: Defined Benefit Pension Plans Postretirement Health ($ millions) Year Ended December 31, Year Ended December 31, 2023 2022 2023 2022 Changes in Benefit Obligations: Obligations at beginning of period $ 527.3 $ 696.2 $ 95.3 $ 131.1 Actuarial (gains) losses, net (25.2) (138.0) 1.4 (27.0) Service costs 2.9 2.7 — — Interest costs 27.8 19.1 5.0 3.5 Benefits paid from plan assets (50.2) (50.0) (10.4) (12.3) Benefits paid from Company assets (0.4) (0.4) — — Plan amendments 0.4 — — — Settlements (171.4) — — — Administrative expenses paid (3.0) (2.3) — — Obligations at end of period 308.2 527.3 91.3 95.3 Changes in Plan Assets: Fair value of plan assets at beginning of period 483.3 672.7 3.5 9.2 Actual return on plan assets 31.8 (137.1) 0.1 (0.1) Company contributions 0.4 0.4 6.8 6.7 Benefits paid (50.6) (50.4) (10.4) (12.3) Settlements (171.4) — — — Administrative expenses paid (3.0) (2.3) — — Fair value of plan assets at end of period 290.5 483.3 — 3.5 Unfunded status at end of period $ (17.7) $ (44.0) $ (91.3) $ (91.8) Amounts recognized in assets and liabilities: Current liabilities $ (0.4) $ (0.4) $ (10.1) $ (7.3) Non current liabilities (17.3) (43.6) (81.2) (84.5) $ (17.7) $ (44.0) $ (91.3) $ (91.8) Amounts in accumulated other comprehensive income (loss), pre-tax: Prior service credit $ (0.1) $ (0.7) $ (1.8) $ (1.9)
Schedule of Net Benefit Costs [Table Text Block]	Components of Net Periodic Benefit Costs and Other Amounts Recognized in Other Comprehensive Income The Company reports service costs for its defined benefit pension plans and its postretirement health and life benefit plans in Cost of Sales and Selling, General and Administrative Expenses . The remaining components of net periodic benefit (credits) costs are reported as Nonoperating Components of Net Periodic Benefit Income. Defined Benefit Pension Plans Postretirement Health (in millions) Year Ended December 31, Year Ended December 31, 2023 2022 2021 2023 2022 2021 Net Periodic Benefit (Credits) Costs Service costs $ 2.9 $ 2.7 $ 2.7 $ — $ — $ — Interest costs 27.8 19.1 18.1 5.0 3.5 3.4 Expected return on plan assets (31.0) (35.6) (38.3) (0.1) (0.1) — Amortization of prior service credits, net (0.2) (0.2) (0.2) (0.1) (0.1) (0.1) Actuarial (gains) losses, net (26.0) 34.7 (48.2) 1.4 (26.9) (2.3) Net periodic benefit (credits) costs $ (26.5) $ 20.7 $ (65.9) $ 6.2 $ (23.6) $ 1.0 Other Changes in Plan Assets and Benefit Obligations Recognized in Other Comprehensive Income (Loss) Amortization of prior service costs, net $ — $ — $ — $ (1.8) $ (1.9) $ (2.0) Prior service credit (0.1) (0.7) (0.9) — — — Total recognized in other comprehensive loss, pre-tax $ (0.1) $ (0.7) $ (0.9) $ (1.8) $ (1.9) $ (2.0) Total recognized in net periodic benefit costs (income) and other comprehensive income (loss), pre-tax $ (26.6) $ 20.0 $ (66.8) $ 4.4 $ (25.5) $ (1.0)
Schedule of Assumptions Used [Table Text Block]	Assumptions Used to Determine Net Periodic Benefit Costs Defined Benefit Pension Plans Postretirement Health Year Ended December 31, Year Ended December 31, 2023 2022 2021 2023 2022 2021 Discount rate 5.2% 5.5% 2.8% 5.2% 5.5% 2.8% Expected return on plan assets 6.8% 5.5% 6.3% 4.0% 0.8% —
Schedule of Health Care Cost Trend Rates [Table Text Block]	Healthcare cost trend rates used to measure postretirement health benefit obligations follow: December 31, 2023 2022 Healthcare cost trend rate for the following year 7.0% 7.0% Long-term rate that the healthcare cost trend rate gradually declines to 5% 5% Year that the healthcare cost trend rate is expected to reach the long-term rate 2032 2031
Schedule of Allocation of Plan Assets [Table Text Block]	Plan assets are measured at fair value. Following are the plan investments as of December 31, 2023 and 2022, categorized by the fair value hierarchy levels described in Note 10, Fair Value : Defined Benefit Pension and Postretirement Health and Life Benefit Plans (in millions) Level 1 Level 2 Level 3 Total 2023 2022 2023 2022 2023 2022 2023 2022 U.S. government securities $ — $ — $ — $ — $ — $ — $ — $ — Corporate debt — — 9.6 60.3 — — 9.6 60.3 Municipal bonds and non-U.S. government securities — — — — — — — — Mutual funds (b) 245.7 320.4 — — — — 245.7 320.4 Mortgage and asset backed securities — — — — — — — — Fair value of investments by hierarchy level $ 245.7 $ 320.4 $ 9.6 $ 60.3 $ — $ — 255.3 380.7 Investments measured at NAV (a) 35.2 105.8 Accrued interest receivable 0.5 0.6 Unsettled transactions — (0.3) Plan assets $ 291.0 $ 486.8
Schedule of Expected Benefit Payments [Table Text Block]	Estimated future benefit plan payments follow (in millions): Defined Benefit Pension Plans Postretirement Health and Life Benefit Plans 2024 $ 30.0 $ 10.1 2025 28.5 9.5 2026 28.6 9.0 2027 26.9 8.4 2028 26.1 7.8 2029 to 2033 120.1 31.6

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	3 Months Ended	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2023
Share-Based Payment Arrangement, Noncash Expense [Abstract]
Schedule of Compensation Cost for Share-based Payment Arrangements, Allocation of Share-based Compensation Costs by Plan [Table Text Block]		A summary of stock-based compensation costs is as follows (in millions): Year Ended December 31, 2023 2022 2021 Notional stock units and stock appreciation rights $ 1.0 $ 0.9 $ 11.6 Restricted stock 0.4 0.2 — BOD and employee restricted stock units 0.9 0.7 0.5 Stock options — 0.1 0.1 Total stock-based compensation costs $ 2.3 $ 1.9 $ 12.2 Total recognized tax benefit $ (0.3) $ (0.2) $ (1.5)
Share-based Payment Arrangement, Nonemployee Director Award Plan, Activity [Table Text Block]		The following table summarizes Centrus’ board restricted stock units activity: Shares (in thousands) Weighted Average Grant Date Fair Value (per share) Nonvested at December 31, 2020 47 $10.38 Granted 20 $25.13 Vested (47) $10.38 Forfeited — — Nonvested at December 31, 2021 20 $25.13 Granted 28 $38.80 Vested (20) $25.13 Forfeited — — Nonvested at December 31, 2022 28 $38.80 Granted 17 $35.95 Vested (28) $38.80 Forfeited — — Nonvested at December 31, 2023 17 $35.95
Schedule of Nonvested Restricted Stock Units Activity [Table Text Block]		The following table summarizes Centrus’ employee restricted stock units activity: Shares Weighted Average Grant Date Fair Value (per share) Nonvested at December 31, 2020 — — Granted 4 $24.01 Vested — — Forfeited — — Nonvested at December 31, 2021 4 $24.01 Granted — — Vested (1) $24.01 Forfeited — — Nonvested at December 31, 2022 3 $24.01 Granted 20 $55.54 Vested (1) $24.01 Forfeited (1) $24.01 Nonvested at December 31, 2023 21 $54.04
Share-based Compensation, Stock Options, Activity [Table Text Block]		A summary of stock option activity follows: Stock Options (in thousands) Weighted Average Exercise Price Weighted Average Remaining Contractual Life in Years Aggregate Intrinsic Value (in millions) Outstanding at December 31, 2020 411 $4.18 5.3 $7.8 Granted — — — — Exercised (217) $4.17 — — Forfeited/Cancelled — — — — Outstanding at December 31, 2021 194 $4.18 4.4 $8.9 Granted — — — — Exercised (98) $4.00 — — Forfeited/Cancelled — — — — Outstanding at December 31, 2022 96 $4.37 2.2 $2.7 Granted — — — — Exercised — — — — Forfeited/Cancelled — — — — Outstanding at December 31, 2023 96 $4.37 0.3 $4.8 Exercisable at December 31, 2023 96 $4.37 0.3 $4.8
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding and Exercisable [Table Text Block]		Stock options outstanding and options exercisable at December 31, 2023, are as follows: Stock Exercise Price Options Outstanding (thousands) Remaining Contractual Life in Years Options Exercisable (thousands) $4.37 96 0.3 96
Share-based Payment Arrangement, Stock Appreciation Right, Activity [Table Text Block]		A summary of SARs with time-based vesting granted under the 2014 Plan for the year ended December 31, 2023, are as follows: Stock Appreciation Rights (in thousands) Weighted Average Exercise Price Weighted Average Remaining Contractual Life in Years Aggregate Intrinsic Value (in millions) Outstanding at December 31, 2020 84 $5.53 2.3 $1.5 Granted — — — — Exercised — — — — Forfeited/Cancelled — — — — Outstanding at December 31, 2021 84 $5.53 1.3 $3.7 Granted — — — — Exercised — — — — Forfeited/Cancelled (14) $5.53 — — Outstanding at December 31, 2022 70 $5.53 0.3 $2.7 Granted — — — — Exercised (74) $5.53 — — Forfeited/Cancelled 4 $5.53 — — Outstanding at December 31, 2023 — — — — Exercisable at December 31, 2023 — — — —
Share-based Payment Arrangement, Stock Appreciation Right, Performance Condition, Activity [Table Text Block]	A summary of SARs with performance-based vesting granted under the 2014 Plan in the year ended December 31, 2023, are as follows: Stock Appreciation Rights (Performance Condition) (in thousands) Weighted Average Exercise Price Weighted Average Remaining Contractual Life in Years Aggregate Intrinsic Value (in millions) Outstanding at December 31, 2020 — — — — Granted 21 $19.44 — — Exercised — — — — Forfeited/Cancelled — — — — Outstanding at December 31, 2021 21 $19.44 2.3 $0.6 Granted — — — — Exercised — — — — Forfeited/Cancelled (3) $19.44 — — Outstanding at December 31, 2022 18 $19.44 1.3 — Granted — — — — Exercised — — — — Forfeited/Cancelled (1) $19.44 — — Outstanding at December 31, 2023 17 $19.44 0.2 $0.3 Exercisable at December 31, 2023 17 $19.44 0.2 $0.3
Schedule of Share-based Payment Award, Stock Appreciation Rights, Performance Condition, Valuation Assumptions [Table Text Block]		The weighted-average assumptions used in the valuation models to determine the fair value of SARs granted to employees under the 2014 Plan are as follows: Year Ended December 31, 2023 2022 2021 Stock Appreciation Rights Granted (in thousands) n/a n/a 21.0 Average Risk-Free Rate n/a n/a 0.3% Expected Volatility n/a n/a 82.8% Expected Term (Years) n/a n/a 2.5 Dividend Yield n/a n/a —
Schedule of Notional Stock Units, Activity [Table Text Block]		A summary of notional stock units with time-based vesting granted under the 2014 Plan for the year ended December 31, 2023, are as follows: Shares (thousands) Weighted Average Grant Date Fair Value (per share) Nonvested at December 31, 2020 571 $3.68 Granted — — Vested (319) — Forfeited/Cancelled — — Nonvested at December 31, 2021 252 $4.33 Granted — — Vested (128) $3.16 Forfeited (2) $5.53 Nonvested at December 31, 2022 122 $5.53 Granted — — Vested (104) $5.53 Forfeited (18) $5.53 Nonvested at December 31, 2023 — —
Schedule of Notional Stock Units, Performance Condition, Activity [Table Text Block]		A summary of notional stock units with performance-based vesting granted under the 2014 Plan for the year ended December 31, 2023, are as follows: Shares Weighted Average Grant Date Fair Value (per share) Nonvested at December 31, 2020 — — Granted 10 $39.55 Vested — — Forfeited — — Nonvested at December 31, 2021 10 $39.55 Granted — — Vested — — Forfeited (2) $39.55 Nonvested at December 31, 2022 8 $39.55 Granted — — Vested — — Forfeited — — Nonvested at December 31, 2023 8 $39.55 Restricted Stock (Performance Condition) - 2022 Award A summary of restricted stock with performance-based vesting granted under the 2014 Plan for the year ended December 31, 2023, are as follows: Shares Weighted Average Grant Date Fair Value (per share) Nonvested at December 31, 2021 — — Granted 24 $33.70 Vested — — Forfeited (2) $33.70 Nonvested at December 31, 2022 22 $33.70 Granted — — Vested — — Forfeited (5) $33.70 Nonvested at December 31, 2023 17 $33.70 A summary of restricted stock with performance-based vesting granted under the 2014 Plan for the year ended December 31, 2023, are as follows: Shares Weighted Average Grant Date Fair Value (per share) Nonvested at December 31, 2022 — — Granted 17 $42.70 Vested — — Forfeited (6) $42.70 Nonvested at December 31, 2023 11 $42.70

Income Taxes Income Taxes (Tabl

Income Taxes Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2023
Income Tax Disclosure [Abstract]
Schedule of Components of Income Tax Expense (Benefit) [Table Text Block]	The income tax expense (benefit) is as follows (in millions): Year Ended December 31, 2023 2022 2021 Current: Federal $ — $ — $ — State and local 1.6 1.0 0.4 Foreign — — — 1.6 1.0 0.4 Deferred: Federal (a) (0.7) 14.9 (40.7) State and local (0.8) (0.3) 1.2 Foreign — — — (1.5) 14.6 (39.5) Income tax expense (benefit) $ 0.1 $ 15.6 $ (39.1)
Schedule of Deferred Tax Assets and Liabilities [Table Text Block]	Future tax consequences of temporary differences between the carrying amounts for financial reporting purposes and the Company’s estimate of the tax bases of its assets and liabilities result in deferred tax assets and liabilities, as follows (in millions): December 31, 2023 2022 Deferred tax assets: Employee benefits costs $ 27.1 $ 33.5 Inventory 31.3 21.3 Property, plant and equipment 178.0 190.2 Research and experimental expenditures 3.3 3.5 Net operating loss and credit carryforwards 172.0 188.6 Accrued expenses 0.4 4.9 Long-term debt and financing costs 5.5 7.6 Lease liability 0.8 2.1 Other 0.6 0.4 Deferred tax assets 419.0 452.1 Valuation allowance (382.4) (414.1) Deferred tax assets, net of valuation allowance $ 36.6 $ 38.0 Deferred tax liabilities: Intangible assets $ 7.1 $ 9.0 Lease asset 0.6 1.8 Prepaid expenses 0.4 0.4 Deferred tax liabilities $ 8.1 $ 11.2 Deferred tax assets, net $ 28.5 $ 26.8
Schedule of Effective Income Tax Rate Reconciliation [Table Text Block]	A reconciliation of income taxes calculated based on the federal statutory income tax rate and the effective tax rate follows: Year Ended December 31, 2023 2022 2021 Federal statutory tax rate 21 % 21 % 21 % Valuation allowance against net deferred tax assets (38) (1) (53) State rate changes 15 2 1 Executive compensation 1 1 1 State income tax expense, net of federal benefit — (1) 1 Uncertain tax positions 1 1 — Effective tax rate — % 23 % (29) %
Summary of Income Tax Contingencies [Table Text Block]	A reconciliation of the beginning and ending amount of unrecognized tax benefits follows (in millions): Year Ended December 31, 2023 2022 Balance at beginning of the period $ 1.9 $ 1.0 Additions to tax positions of current period 1.0 0.9 Reductions to tax positions of prior years — — Balance at end of the period $ 2.9 $ 1.9

Net Income Per Share (Tables)

Net Income Per Share (Tables)	12 Months Ended
	Dec. 31, 2023
Earnings Per Share [Abstract]
Schedule of Net Income Per Share	The weighted average number of common and common equivalent shares and the calculation of basic and diluted income per common share are as follows: Year Ended December 31, 2023 2022 2021 Numerator (in millions): Net income $ 84.4 $ 52.2 $ 175.0 Warrant modification — 1.5 — Preferred stock dividends - undeclared and cumulative — — 2.1 Distributed earnings allocable to retired preferred shares — — 37.6 Net income allocable to common stockholders $ 84.4 $ 50.7 $ 135.3 Denominator (in thousands): Average common shares outstanding - basic 15,212 14,601 13,493 Potentially dilutive shares related to stock compensation awards and warrant 289 387 386 Average common shares outstanding - diluted 15,501 14,988 13,879 Net income per common share (in dollars): Basic $ 5.55 $ 3.47 $ 10.03 Diluted $ 5.44 $ 3.38 $ 9.75

Stockholders' Equity (Tables)

Stockholders' Equity (Tables)	12 Months Ended
	Dec. 31, 2023
Equity, Attributable to Parent [Abstract]
Schedule of Stock by Class [Table Text Block]	Changes in the number of shares outstanding are as follows: Preferred Stock, Common Stock, Common Stock, Balance at December 31, 2020 41,720 11,390,189 719,200 Issuance under public offering — 1,516,467 — Common stock issued for options exercised — 216,500 — Issuance of previously vested restricted stock units — 89,318 — Notional stock units paid in shares — 206,183 — Common stock and warrant issued in exchange for preferred stock (3,873) 231,276 — Purchase under tender offer (37,847) — — Balance at December 31, 2021 — 13,649,933 719,200 Issuance under public offering — 99,090 — Common stock issued for options exercised — 98,000 — Issuance of previously vested restricted stock units — 1,172 — Notional stock units paid in shares — 71,451 — Balance at December 31, 2022 — 13,919,646 719,200 Issuance under public offering — 722,568 — Issuance of previously vested restricted stock units — 45,437 — Notional stock units paid in shares — 119,604 — Exercise of outstanding warrant — 149,179 — Balance at December 31, 2023 — 14,956,434 719,200

Segment Information (Tables)

Segment Information (Tables)	12 Months Ended
	Dec. 31, 2023
Segment Reporting Information, Revenue for Reportable Segment [Abstract]
Revenue from External Customers by Geographic Areas	The following table presents revenue from SWU and uranium sales disaggregated by geographical region, including foreign countries representing 10% or more of revenue, based on the billing addresses of customers (in millions): Year Ended December 31, 2023 2022 2021 United States $ 230.4 $ 96.1 $ 108.3 Foreign: Belgium 0.1 38.3 36.6 Japan 23.6 61.6 34.6 Other 14.9 39.6 6.6 Total foreign 38.6 139.5 77.8 Revenue - SWU and uranium $ 269.0 $ 235.6 $ 186.1 Revenue by customer location, including customers in a foreign country representing 10% or more of total revenue, follows (in millions): Year Ended December 31, 2023 2022 2021 United States $ 281.6 $ 154.3 $ 220.5 Foreign: Belgium 0.1 38.3 36.6 Japan 23.6 61.6 34.6 Other 14.9 39.6 6.6 Total foreign 38.6 139.5 77.8 Total revenue $ 320.2 $ 293.8 $ 298.3
Segment Reporting Information	The following table presents the Company’s segment information (in millions): Year Ended December 31, 2023 2022 2021 Revenue LEU segment: Separative work units $ 208.2 $ 196.2 $ 163.3 Uranium 60.8 39.4 22.8 Intersegment revenue, eliminated on consolidation 5.0 — — Total 274.0 235.6 186.1 Technical Solutions segment 51.2 58.2 112.2 Total revenue 325.2 293.8 298.3 Elimination of intersegment revenue (5.0) — — Total revenue $ 320.2 $ 293.8 $ 298.3 Segment Gross Profit (Loss) LEU segment: LEU segment $ 105.1 $ 130.6 $ 73.0 Intersegment gross profit, eliminated on consolidation 2.0 — — Total 107.1 130.6 73.0 Technical Solutions segment: Technical Solutions segment 7.0 (12.7) 41.5 Intersegment gross profit, eliminated on consolidation 3.0 Total 10.0 (12.7) 41.5 Elimination of intersegment gross profit (5.0) — — Gross profit $ 112.1 $ 117.9 $ 114.5 The Company’s total assets are not presented for each reportable segment as they are not reviewed by, nor otherwise regularly provided to the chief operating decision maker. Centrus’ long-term or long-lived assets, which include property, plant and equipment and other assets reported on the Consolidated Balance Sheet, were located in the United States as of December 31, 2023, and December 31, 2022.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Details)	12 Months Ended
	Dec. 31, 2023
Average useful life of finite-lived intangible assets	15 years
Concentration Risk, Supplier	Concentrations of Supply Risk and Other Considerations with the War in Ukraine The current war in Ukraine has led to the U.S., Russia and other countries imposing sanctions and other measures that restrict international trade. The situation is rapidly changing, and it is not possible to predict future actions that could be taken. The Company has multiple sources of supply; however, the supply contract with TENEX remains the Company’s largest source and accounts for well over one-half of or its anticipated supply in 2024-2027 for deliveries to U.S. customers. At present, sanctions have not impacted the ability of the Company or TENEX to perform under the TENEX Supply Contract. Recently, sanctions have been imposed by the U.S. on exports of fossil fuels. Russia has imposed sanctions on the export of commodities but does not include the export of LEU. Canada has imposed sanctions on ocean transportation of Russian LEU, but has given a permit to the Company’s carrier that extends to early July 2024. Additional sanctions or other measures by the U.S. or foreign governments (including the Russian government) could be imposed or the existing Canadian permit might not be extended. Any sanctions or measures directed at trade in LEU from Russia or the parties involved in such trade or otherwise, including denial or non-renewal of licenses or permits, could interfere with, or prevent, implementation of the TENEX Supply Contract. While the initial sanctions announced do not affect the ability of the Company or TENEX to implement the TENEX Supply Contract, the situation at this time is unpredictable and there are proposals in Congress (including one that has passed the House of Representatives) to impose a ban on imports of Russian LEU. If a ban were enacted or measures were taken to limit the supply of Russian LEU or to prohibit or limit dealings with Russian entities, including, but not limited to, TENEX or Rosatom, the Company would seek a license, waiver or other approval from the government imposing such measures to ensure that the Company could continue to fulfill its purchase and sales obligations. There is no assurance that such a license, waiver, or approval would be granted. If a license, waiver or approval were not granted, the Company would need to look to alternative sources of LEU to replace the LEU that it could not procure from TENEX. The Company has contracts for alternative sources that could be used to mitigate a portion of the near term impacts. However, the Company’s alternative sources are not sufficient to replace all of the Russian LEU the Company is currently permitted to import under the RSA, and to the extent additional supply cannot be obtained, or obtained at a higher costs, it will have a material adverse impact on its business, results of operations, and competitive position.Given the foregoing, there is no assurance that future developments would not have a material adverse effect on the Company’s procurement, payment, delivery or sale of LEU under the TENEX Supply Contract and well as on our business, results of operations, and competitive position.
Related Party Transaction, Description of Transaction	Related Party As previously disclosed in the Company’s Current Report on Form 8-K filed on December 31, 2020, on that same date the Company entered into an At Market Sales Agreement (the “Sales Agreement”) with B. Riley Securities, Inc. and Lake Street Capital Markets, LLC, relating to an ATM offering of shares of the Company’s Class A Common Stock. Mr. Williams, Chairman of the Centrus Board of Directors, also served on the board of B. Riley Financial, Inc. Mr. Williams recused himself and took no part in the selection of B. Riley or the negotiation of the terms of the Sales Agreement. The Company filed a shelf registration statement on Form S-3 (Registration Statement No. 333-272984) with the SEC on June 28, 2023, which became effective on July 10, 2023. Pursuant to this shelf registration statement, the Company may offer and sell up to $200 million in securities, in aggregate. The Company may continue to work with B. Riley Securities, Inc. for any offerings under this registration statement. Mr. Williams is an employee of Targus International LLC whose ultimate parent has been B. Riley Financial, Inc since 2022. Please refer to Note 16, Stockholders’ Equity, for further details.Foreign CurrencyThe Company records foreign currency transaction gains and losses, realized and unrealized, and foreign exchange gains and losses due to re-measurement of monetary assets and liabilities that are not denominated in U.S. dollars in other income, net in the Consolidated Statements of Operations.
Senior Notes [Member]
Debt Instrument, Interest Rate, Stated Percentage	8.25%

Revenue and Contracts with Cu_2

Revenue and Contracts with Customers (Narrative) (Details) - USD ($) $ in Millions		1 Months Ended			12 Months Ended			13 Months Ended	36 Months Ended	60 Months Ended
	Oct. 19, 2023	Oct. 31, 2022	May 31, 2022	Mar. 31, 2022	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2023	Dec. 31, 2020	Dec. 31, 2023
Revenue, nonmonetary transaction					$ 14.8	$ 14.5	$ 0
Deferred revenue, additions in period					33.4	33.7
Deferred revenue, revenue recognized					23.6	62.4
Separative work units borrowed in period, value		$ 10.4	$ 8.5	$ 9.4					$ 20.7
Separative work units owed to others noncurrent					11.1		3.1	$ 11.1		$ 11.1
Government cost share portion					173			173		173
Provision for Loss on Contracts					0	20		0		0
Accounts receivable, net					49.4	38.1		49.4		49.4
Gain (loss) related to litigation settlement							43.5
Revenue, remaining performance obligation, amount					1,000			1,000		1,000
Deferred Revenue and Advances from Customers - Current and Noncurrent					315	319		315		315
Provision for loss on contracts utilized					0	0.5	(7.2)			19.6
Contract with Customer, Advances, Liability					63	61		63		63
accrued loss						21.3
HALEU Ops Contract
Provision for loss on contracts total					0	20		0		0
Cost obligated to DOE								59.4
Total Amount Program Cost								125.9
Contract Value					150			150		150
Additional costs obligated to DOE	$ 5.5
HALEU Ops Contract | Phase 2
Contract Value					90			90		90
HALEU Demo Contract
Provision for loss on contracts total						0
Maximum [Member] | HALEU Ops Contract | Phase 1
Government cost share portion					30			30		30
Company cost share portion					30			30		30
Pension Plan, Defined Benefit [Member]
Gain (loss) related to litigation settlement							33.8
Other Postretirement Benefits Plan [Member]
Gain (loss) related to litigation settlement							$ 9.7
Government [Member]
Proceeds from Customers								$ 32.6		$ 171.2
Government [Member] | HALEU Ops Contract
Provision for loss on contracts utilized					$ 20	$ 1.3

Revenue and Contracts with Cu_3

Revenue and Contracts with Customers (Revenue from External Customers by Geographic Areas) (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Revenue		$ 320.2	$ 293.8	$ 298.3
United States
Revenue		281.6	154.3	220.5
Belgium
Revenue	$ 0.1		38.3	36.6
Japan
Revenue		23.6	61.6	34.6
Other Foreign
Revenue		14.9	39.6	6.6
Foreign
Revenue		38.6	139.5	77.8
Product [Member]
Revenue		269	235.6	186.1
Product [Member] | United States
Revenue		230.4	96.1	108.3
Product [Member] | Belgium
Revenue		0.1	38.3	36.6
Product [Member] | Japan
Revenue		23.6	61.6	34.6
Product [Member] | Other Foreign
Revenue		14.9	39.6	6.6
Product [Member] | Foreign
Revenue		$ 38.6	$ 139.5	$ 77.8

Revenue and Contracts with Cu_4

Revenue and Contracts with Customers (Contract with Customer Asset and Liability) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Deferred costs associated with deferred revenue	$ 117.6	$ 135.7
Provision for Loss on Contracts	0	20
Provision for loss on contract change	(20)
Deferred revenue	252.4	258.4
Deferred revenue change	(6)
Advances from customers	30.2	14.8
Advances from customers change	15.4
Contract with Customer, Advances, Liability, Noncurrent	32.8	$ 46.2
Advances from customers, noncurrent, change	$ (13.4)

Revenue and Contracts with Cu_5

Revenue and Contracts with Customers Accounts Receivable (Schedule of Accounts Receivable) (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Accounts, Notes, Loans and Financing Receivable [Line Items]
Billed Contracts Receivable	$ 40.2	$ 29
Unbilled Receivables, Current	9.2	9.1
Accounts receivable, net	$ 49.4	$ 38.1

Cash, Cash Equivalents and Re_3

Cash, Cash Equivalents and Restricted Cash (Schedule of Cash, Cash Equivalents and Restricted Cash) (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Cash and Cash Equivalents [Line Items]
Cash and cash equivalents	$ 201.2	$ 179.9
Restricted cash included in other current assets	0.2	0.2
Restricted cash included in other long-term assets	32.4	32.3
Total cash, cash equivalents and restricted cash	$ 233.8	$ 212.4	$ 196.8	$ 157.9

Cash, Cash Equivalents and Re_4

Cash, Cash Equivalents and Restricted Cash (Schedule of Restricted Cash) (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Restricted Cash and Cash Equivalents Items [Line Items]
Restricted cash included in other current assets	$ 0.2	$ 0.2
Restricted cash included in other long-term assets	32.4	32.3
Other financial assurance [Member]
Restricted Cash and Cash Equivalents Items [Line Items]
Restricted cash included in other current assets	0.2	0.2
Restricted cash included in other long-term assets	0.1	0.1
Workers compensation financial assurance [Member]
Restricted Cash and Cash Equivalents Items [Line Items]
Restricted cash included in other current assets	0	0
Restricted cash included in other long-term assets	2.5	2.4
Collateral for Inventory Loan
Restricted Cash and Cash Equivalents Items [Line Items]
Restricted cash included in other current assets	0	0
Restricted cash included in other long-term assets	$ 29.8	$ 29.8

Cash, Cash Equivalents and Re_5

Cash, Cash Equivalents and Restricted Cash (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Cash and Cash Equivalents, Held in Foreign Currency	$ 6.8	$ 0
Unrealized Gain (Loss), Foreign Currency Transaction, before Tax	$ 0.1	$ 0.1	$ 0.1

Inventories (Schedule of Invent

Inventories (Schedule of Inventories) (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Inventory, Net [Abstract]
Separative work units inventory	$ 21.9	$ 24.1
Uranium inventory	284.5	185.1
Inventories	306.4	209.2
Separative work units owed to customers and suppliers	0	0
Uranium owed to customers and suppliers	84.3	60.8
Inventories owed to customers and suppliers	84.3	60.8
Separative work units net of liability	21.9	24.1
Uranium inventory net of liability	200.2	124.3
Inventories, net	$ 222.1	$ 148.4

Inventories (Narrative) (Detail

Inventories (Narrative) (Details) - USD ($) $ in Millions	1 Months Ended			12 Months Ended			36 Months Ended
	Oct. 31, 2022	May 31, 2022	Mar. 31, 2022	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Inventory, Net [Abstract]
Separative work units borrowed in period, value	$ 10.4	$ 8.5	$ 9.4				$ 20.7
Separative work units repaid in period, value				$ (11.1)
Separative work units valuation change in period				7.4	$ 7.9	$ 4.8
Separative work units owed to others noncurrent				11.1		$ 3.1
UF6 units borrowed in period				$ 22.5

Property, Plant and Equipment_2

Property, Plant and Equipment (Tables) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 11.3	$ 9.1
Property, Plant and Equipment, Additions	2.2
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment	(4.3)	(3.6)
Accumulated Depreciation, Depletion and Amortization, Sale or Disposal of Property, Plant and Equipment	(0.7)
Property, Plant And Equipment, Net Capital Expenditures	1.5
Property, Plant and Equipment, Net	7	5.5
Depreciation	(0.7)	(0.6)	$ (0.6)
Land [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	1.2	1.2
Property, Plant and Equipment, Additions	0
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	5	4.8
Property, Plant and Equipment, Additions	0.2
Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	3.8	2
Property, Plant and Equipment, Additions	1.8
Other Capitalized Property Plant and Equipment [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	1.3	$ 1.1
Property, Plant and Equipment, Additions	$ 0.2

Property, Plant and Equipment_3

Property, Plant and Equipment (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Property, Plant and Equipment [Abstract]
Depreciation	$ 0.7	$ 0.6	$ 0.6

Schedule of Intangible Assets (

Schedule of Intangible Assets (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Finite-Lived Intangible Assets [Line Items]
Amortizable intangible assets, gross	$ 123.5	$ 123.5
Accumulated intangible asset amortization	(84.1)	(77.8)
Amortizable intangible assets, net	$ 39.4	45.7
Average useful life of finite-lived intangible assets	15 years
Contract-Based Intangible Assets [Member]
Finite-Lived Intangible Assets [Line Items]
Amortizable intangible assets, gross	$ 54.6	54.6
Accumulated intangible asset amortization	(41.6)	(39.9)
Amortizable intangible assets, net	13	14.7
Customer-Related Intangible Assets [Member]
Finite-Lived Intangible Assets [Line Items]
Amortizable intangible assets, gross	68.9	68.9
Accumulated intangible asset amortization	(42.5)	(37.9)
Amortizable intangible assets, net	$ 26.4	$ 31

Intangible Assets Schedule of I

Intangible Assets Schedule of Intangible Asset Amortization (Details) $ in Millions	Dec. 31, 2023 USD ($)
Intangible Assets Disclosure [Abstract]
Finite-Lived Intangible Assets, Amortization Expense, Next Twelve Months	$ 8.9
Finite-Lived Intangible Assets, Amortization Expense, Year Two	9.1
Finite-Lived Intangible Assets, Amortization Expense, Year Three	7.4
Finite-Lived Intangible Assets, Amortization Expense, Year Four	6
Finite-Lived Intangible Assets, Amortization Expense, Year Five	4.6
Finite-Lived Intangible Assets, Amortization Expense, after Year Five	3.4
Finite-Lived Intangible Assets, Net	$ 39.4

Accounts Payable and Accrued _3

Accounts Payable and Accrued Liabilities (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Trade payables	$ 6.1	$ 5.9
Postretirement health and life benefit obligations - current	10.1	7.3
Compensation and benefits payable	21.1	15.7
Provision for Loss on Contracts	0	20
Short-term inventory loan	14.3	9.9
Operating Lease, Liability, Current	1.4	3.3
Other accrued liabilities	3.2	3.4
Accounts payable and accrued liabilities	$ 56.2	$ 65.5

Schedule of Debt (Details)

Schedule of Debt (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Debt Instrument [Line Items]
Long-term debt	$ 89.6	$ 95.7
Senior Notes [Member]
Debt Instrument [Line Items]
Long-term debt, face amount	74.3	74.3
Long-term debt, interest	15.3	21.4
Long-term debt, current	6.1	6.1
Long-term debt	$ 89.6	$ 95.7

Debt (Narrative) (Details)

Debt (Narrative) (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2017
Preferred stock, shares issued			104,574
Subordination to credit facility, facility total	$ 50
Subordination to credit facility, facility maximum net borrowing	$ 40
Senior Notes [Member]
Debt instrument interest rate	8.25%
Long-term debt, face amount	$ 74.3	$ 74.3
Long-term debt, current	$ 6.1	$ 6.1

Leases (Narrative) (Details)

Leases (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Leases [Abstract]
Operating Lease, Weighted Average Remaining Lease Term	3 years 1 month 6 days	3 years 7 months 6 days
Operating Lease, Weighted Average Discount Rate, Percent	11.30%	10.10%
Operating Lease, Right-of-Use Asset	$ 2.7	$ 7.9
Operating Lease, Liability, Current	1.4	3.3
Operating Lease, Liability, Noncurrent	2.6	6.1
Operating Lease, Liability	4	9.4
Operating Lease, Expense	(0.1)	(0.7)	$ (0.5)
Operating Lease, Expense Adjustment	(1.5)	(1.6)	(2)
Operating Lease, Payments	$ (1.7)	(1.6)	$ (2.4)
Operating Lease, Liability, Decrease		$ (1)
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible List]	Other long-term assets	Other long-term assets
Operating Lease, Liability, Current, Statement of Financial Position [Extensible List]	Accounts payable and accrued liabilities	Accounts payable and accrued liabilities
Operating Lease, Liability, Noncurrent, Statement of Financial Position [Extensible List]	Other long-term liabilities	Other long-term liabilities
Increase (Decrease) in Operating Lease Liability	$ 6.6

Maturity of Operating Lease Lia

Maturity of Operating Lease Liabilities (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Leases [Abstract]
Lessee, Operating Lease, Liability, Payments, Due Next Twelve Months	$ 1.9
Lessee, Operating Lease, Liability, Payments, Due Year Two	1.9
Lessee, Operating Lease, Liability, Payments, Due Year Three	1
Lessee, Operating Lease, Liability, Payments, Due Year Four	0.8
Lessee, Operating Lease, Liability, Payments, Due Year Five	0
Lessee, Operating Lease, Liability, Payments, Due after Year Five	0
Lessee, Operating Lease, Liability, Payments, Due	5.6
Lessee, Operating Lease, Liability, Undiscounted Excess Amount	1.6
Operating Lease, Liability	$ 4	$ 9.4

Fair Value Measurements (Financ

Fair Value Measurements (Financial Instruments Recorded at Fair Value) (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Cash and cash equivalents	$ 201.2	$ 179.9
Cash and cash equivalents	201.2	179.9
Deferred compensation asset	3.3	2.4
Deferred compensation obligation	3.3	2.4
Fair Value, Inputs, Level 1 [Member]
Cash and cash equivalents	201.2	179.9
Deferred compensation asset	3.3	2.4
Deferred compensation obligation	3.3	2.4
Fair Value, Inputs, Level 2 [Member]
Cash and cash equivalents	0	0
Deferred compensation asset	0	0
Deferred compensation obligation	0	0
Fair Value, Inputs, Level 3 [Member]
Cash and cash equivalents	0	0
Deferred compensation asset	0	0
Deferred compensation obligation	$ 0	$ 0

Fair Value Measurements (Narrat

Fair Value Measurements (Narrative) (Details) - Senior Notes [Member] - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt, long-term and short-term, combined carrying value	$ 95.7	$ 101.8
Long-term debt, current	6.1	6.1
Long-term debt, fair value	71.7	68.8
Long-term debt, face amount	$ 74.3	$ 74.3

Pension and Postretirement He_3

Pension and Postretirement Health and Life Benefits (Narrative) (Details) $ in Millions	12 Months Ended
	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2015 USD ($)
Gain (loss) related to litigation settlement			$ 43.5
Defined Contribution Plan, Cost	$ 2.3	$ 2.1
Defined Benefit Plan, Actuarial (Gain) Loss From Remeasurement	$ 24.6	(7.8)	50.5
Pension Plan, Defined Benefit [Member]
Approximate Number of Plan Participants	2,900
Gain (loss) related to litigation settlement			33.8
Defined Benefit Plan, Actuarial (Gain) Loss From Remeasurement	$ (25.2)	(138)
Pension Plan, Defined Benefit [Member] | Qualified Plan [Member]
Expected defined benefit plan contributions for next fiscal year for qualified plans	0.4
Pension Plan, Defined Benefit [Member] | Nonqualified Plan [Member]
Expected defined benefit plan contributions for next fiscal year for qualified plans	$ 0.4
Other Postretirement Benefits Plan [Member]
Approximate Number of Plan Participants	2,900
Gain (loss) related to litigation settlement			$ 9.7
Defined Benefit Plan, Accumulated Benefit Obligation, Increase (Decrease) for Plan Amendment				$ (10)	$ (3.6)	$ (6.8)
Expected defined benefit plan contributions for next fiscal year for qualified plans	$ 10.1
Defined Benefit Plan, Actuarial (Gain) Loss From Remeasurement	$ 1.4	$ (27)

Pension and Postretirement He_4

Pension and Postretirement Health and Life Benefits (Schedule of Changes in Projected Benefit Obligations) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Defined Benefit Plan, Actuarial (Gain) Loss From Remeasurement	$ 24.6	$ (7.8)	$ 50.5
Defined Benefit Plan, Plan Assets, Amount	291	486.8
Pension Plan, Defined Benefit [Member]
Defined Benefit Plan, Benefit Obligation	308.2	527.3	696.2
Defined Benefit Plan, Actuarial (Gain) Loss From Remeasurement	(25.2)	(138)
Defined Benefit Plan, Service Cost	2.9	2.7	2.7
Defined Benefit Plan, Interest Cost	27.8	19.1	18.1
Defined Benefit Plan, Benefit Obligation, Increase for Plan Amendment	(0.4)	0
Defined Benefit Plan, Benefit Obligation, (Increase) Decrease for Settlement	(171.4)	0
Defined Benefit Plan, Benefit Obligation, Administrative Expenses Paid	(3)	(2.3)
Defined Benefit Plan, Plan Assets, Amount	290.5	483.3	672.7
Defined Benefit Plan, Plan Assets, Increase (Decrease) for Actual Return (Loss)	31.8	(137.1)
Defined Benefit Plan, Plan Assets, Contributions by Employer	0.4	0.4
Defined Benefit Plan, Plan Assets, Benefits Paid	50.6	50.4
Defined Benefit Plan, Plan Assets, Payment for Settlement	(171.4)	0
Defined Benefit Plan, Plan Assets, Administration Expense	(3)	(2.3)
Defined Benefit Plan, Funded (Unfunded) Status of Plan	(17.7)	(44)
Amounts Recognized In Current Liabilities	(0.4)	(0.4)
Amounts Recognized In Noncurrent Liabilities	(17.3)	(43.6)
Defined Benefit Plan, Amounts for Asset (Liability) Recognized in Statement of Financial Position	(17.7)	(44)
Recognized In Accumulated Other Comprehensive Income Pre Tax Prior Service Cost Credit	(0.1)	(0.7)
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, before Tax	(0.1)	(0.7)	(0.9)
Other Postretirement Benefits Plan [Member]
Defined Benefit Plan, Benefit Obligation	91.3	95.3	131.1
Defined Benefit Plan, Actuarial (Gain) Loss From Remeasurement	1.4	(27)
Defined Benefit Plan, Service Cost	0	0	0
Defined Benefit Plan, Interest Cost	5	3.5	3.4
Defined Benefit Plan, Benefit Obligation, Increase for Plan Amendment	0	0
Defined Benefit Plan, Benefit Obligation, (Increase) Decrease for Settlement	0	0
Defined Benefit Plan, Benefit Obligation, Administrative Expenses Paid	0	0
Defined Benefit Plan, Plan Assets, Amount	0	3.5	9.2
Defined Benefit Plan, Plan Assets, Increase (Decrease) for Actual Return (Loss)	0.1	(0.1)
Defined Benefit Plan, Plan Assets, Contributions by Employer	6.8	6.7
Defined Benefit Plan, Plan Assets, Benefits Paid	10.4	12.3
Defined Benefit Plan, Plan Assets, Payment for Settlement	0	0
Defined Benefit Plan, Plan Assets, Administration Expense	0	0
Defined Benefit Plan, Funded (Unfunded) Status of Plan	(91.3)	(91.8)
Amounts Recognized In Current Liabilities	(10.1)	(7.3)
Amounts Recognized In Noncurrent Liabilities	(81.2)	(84.5)
Defined Benefit Plan, Amounts for Asset (Liability) Recognized in Statement of Financial Position	(91.3)	(91.8)
Recognized In Accumulated Other Comprehensive Income Pre Tax Prior Service Cost Credit	(1.8)	(1.9)
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, before Tax	(1.8)	(1.9)	$ (2)
Plan paid [Member] | Pension Plan, Defined Benefit [Member]
Defined Benefit Plan, Benefit Obligation, Benefits Paid	(50.2)	(50)
Plan paid [Member] | Other Postretirement Benefits Plan [Member]
Defined Benefit Plan, Benefit Obligation, Benefits Paid	(10.4)	(12.3)
Company paid [Member] | Pension Plan, Defined Benefit [Member]
Defined Benefit Plan, Benefit Obligation, Benefits Paid	(0.4)	(0.4)
Company paid [Member] | Other Postretirement Benefits Plan [Member]
Defined Benefit Plan, Benefit Obligation, Benefits Paid	$ 0	$ 0

Pension and Postretirement He_5

Pension and Postretirement Health and Life Benefits (Schedule of Net Benefit Costs) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Defined Benefit Plan, Actuarial (Gain) Loss From Remeasurement	$ 24.6	$ (7.8)	$ 50.5
Pension Plan, Defined Benefit [Member]
Service costs	2.9	2.7	2.7
Interest costs	27.8	19.1	18.1
Expected return on plan assets (gains)	(31)	(35.6)	(38.3)
Amortization of prior service costs (credits), net	(0.2)	(0.2)	(0.2)
Actuarial (gains) losses, net	(26)	34.7	(48.2)
Defined Benefit Plan, Actuarial (Gain) Loss From Remeasurement	(25.2)	(138)
Net periodic benefit cost (credit)	(26.5)	20.7	(65.9)
Postretirement Health and Life Benefits Plans [Member]
Service costs	0	0	0
Interest costs	5	3.5	3.4
Expected return on plan assets (gains)	(0.1)	(0.1)	0
Amortization of prior service costs (credits), net	(0.1)	(0.1)	(0.1)
Actuarial (gains) losses, net	1.4	(26.9)	(2.3)
Defined Benefit Plan, Actuarial (Gain) Loss From Remeasurement	1.4	(27)
Net periodic benefit cost (credit)	$ 6.2	$ (23.6)	$ 1

Pension and Postretirement He_6

Pension and Postretirement Health and Life Benefits (Schedule of Defined Benefit Plan Amounts Recognized in Other Comprehensive Income) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Pension Plan, Defined Benefit [Member]
Other Comprehensive (Income) Loss, Defined Benefit Plan, Prior Service Cost (Credit), Reclassification Adjustment from AOCI, before Tax	$ (0.1)	$ (0.7)	$ (0.9)
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, before Tax	(0.1)	(0.7)	(0.9)
Total recognized in net periodic benefit costs (income) and other comprehensive income (loss), pre-tax	(26.6)	20	(66.8)
Other Postretirement Benefits Plan [Member]
Other Comprehensive (Income) Loss, Defined Benefit Plan, Prior Service Cost (Credit), Reclassification Adjustment from AOCI, before Tax	(1.8)	(1.9)	(2)
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, before Tax	(1.8)	(1.9)	(2)
Total recognized in net periodic benefit costs (income) and other comprehensive income (loss), pre-tax	$ 4.4	$ (25.5)	$ (1)

Pension and Postretirement He_7

Pension and Postretirement Health and Life Benefits (Schedule of Assumptions Used) (Details)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Pension Plan, Defined Benefit [Member]
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Discount Rate	5.20%	5.50%	2.80%
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Expected Long-term Rate of Return on Plan Assets	6.80%	5.50%	6.30%
Other Postretirement Benefits Plan [Member]
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Discount Rate	5.20%	5.50%	2.80%
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Expected Long-term Rate of Return on Plan Assets	4%	0.80%	0%

Pension and Postretirement He_8

Pension and Postretirement Health and Life Benefits (Schedule of Healthcare Cost Trend Rates) (Details)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Defined Benefit Plan, Assumed Health Care Cost Trend Rates [Abstract]
Defined Benefit Plan, Health Care Cost Trend Rate Assumed, Next Fiscal Year	7%	7%
Defined Benefit Plan, Ultimate Health Care Cost Trend Rate	5%	5%
Defined Benefit Plan, Year Health Care Cost Trend Rate Reaches Ultimate Trend Rate	2032	2031

Pension and Postretirement He_9

Pension and Postretirement Health and Life Benefits (Plan Asset Allocations) (Details)	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Defined Benefit Plan, Plan Assets, Actual Allocation, Percentage		100%	100%
Equity Securities [Member]
Defined Benefit Plan, Plan Assets, Actual Allocation, Percentage		42%	36%
Equity Securities [Member] | Scenario, Forecast [Member] | Minimum [Member]
Defined Benefit Plan, Plan Assets, Actual Allocation, Percentage	35%
Equity Securities [Member] | Scenario, Forecast [Member] | Maximum [Member]
Defined Benefit Plan, Plan Assets, Actual Allocation, Percentage	40%
Debt Securities [Member]
Defined Benefit Plan, Plan Assets, Actual Allocation, Percentage		57%	62%
Debt Securities [Member] | Scenario, Forecast [Member] | Minimum [Member]
Defined Benefit Plan, Plan Assets, Actual Allocation, Percentage	55%
Debt Securities [Member] | Scenario, Forecast [Member] | Maximum [Member]
Defined Benefit Plan, Plan Assets, Actual Allocation, Percentage	60%
Cash [Member]
Defined Benefit Plan, Plan Assets, Actual Allocation, Percentage		1%	2%
Cash [Member] | Scenario, Forecast [Member] | Minimum [Member]
Defined Benefit Plan, Plan Assets, Actual Allocation, Percentage	0%
Cash [Member] | Scenario, Forecast [Member] | Maximum [Member]
Defined Benefit Plan, Plan Assets, Actual Allocation, Percentage	5%

Pension and Postretirement H_10

Pension and Postretirement Health and Life Benefits (Schedule of Fair Value of Plan Assets) (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	$ 291	$ 486.8
Defined Benefit Plan, Investments Measured at NAV	35.2	105.8
Accrued interest receivable	0.5	0.6
Unsettled transactions receivable	0	(0.3)
Fair Value, Inputs, Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	245.7	320.4
Fair Value, Inputs, Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	9.6	60.3
Fair Value, Inputs, Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0	0
Fair Value, Inputs, Level 1, 2 and 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	255.3	380.7
US government securities [Member] | Fair Value, Inputs, Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0	0
US government securities [Member] | Fair Value, Inputs, Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0	0
US government securities [Member] | Fair Value, Inputs, Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0	0
US government securities [Member] | Fair Value, Inputs, Level 1, 2 and 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0	0
Corporate debt [Member] | Fair Value, Inputs, Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0	0
Corporate debt [Member] | Fair Value, Inputs, Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	9.6	60.3
Corporate debt [Member] | Fair Value, Inputs, Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0	0
Corporate debt [Member] | Fair Value, Inputs, Level 1, 2 and 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	9.6	60.3
Municipal bonds and non-U.S. government securities [Member] | Fair Value, Inputs, Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0	0
Municipal bonds and non-U.S. government securities [Member] | Fair Value, Inputs, Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0	0
Municipal bonds and non-U.S. government securities [Member] | Fair Value, Inputs, Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0	0
Municipal bonds and non-U.S. government securities [Member] | Fair Value, Inputs, Level 1, 2 and 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0	0
Mutual Fund [Member] | Fair Value, Inputs, Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	245.7	320.4
Mutual Fund [Member] | Fair Value, Inputs, Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0	0
Mutual Fund [Member] | Fair Value, Inputs, Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0	0
Mutual Fund [Member] | Fair Value, Inputs, Level 1, 2 and 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	245.7	320.4
Mortgage and asset backed securities [Member] | Fair Value, Inputs, Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0	0
Mortgage and asset backed securities [Member] | Fair Value, Inputs, Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0	0
Mortgage and asset backed securities [Member] | Fair Value, Inputs, Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0	0
Mortgage and asset backed securities [Member] | Fair Value, Inputs, Level 1, 2 and 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	0	0
Pension Plan, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	290.5	483.3	$ 672.7
Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	$ 0	$ 3.5	$ 9.2

Pension and Postretirement H_11

Pension and Postretirement Health and Life Benefits (Schedule of Estimated Future Benefit Payments) (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Pension Plan, Defined Benefit [Member]
Defined Benefit Plan, Expected Future Benefit Payment, Next Twelve Months	$ 30
Defined Benefit Plan, Expected Future Benefit Payment, Year Two	28.5
Defined Benefit Plan, Expected Future Benefit Payment, Year Three	28.6
Defined Benefit Plan, Expected Future Benefit Payment, Year Four	26.9
Defined Benefit Plan, Expected Future Benefit Payment, Year Five	26.1
Defined Benefit Plan, Expected Future Benefit Payment, Five Fiscal Years Thereafter	$ 120.1
Other Postretirement Benefits Plan [Member]
Defined Benefit Plan, Expected Future Benefit Payment, Next Twelve Months		$ 10.1
Defined Benefit Plan, Expected Future Benefit Payment, Year Two		9.5
Defined Benefit Plan, Expected Future Benefit Payment, Year Three		9
Defined Benefit Plan, Expected Future Benefit Payment, Year Four		8.4
Defined Benefit Plan, Expected Future Benefit Payment, Year Five		7.8
Defined Benefit Plan, Expected Future Benefit Payment, Five Fiscal Years Thereafter		$ 31.6

Compensation Related Costs, R_2

Compensation Related Costs, Retirement Benefits (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Retirement Benefits [Abstract]
Special charges for workforce reductions and advisory costs	$ 3.6	$ 0.5	$ 0

Stock-Based Compensation (Narra

Stock-Based Compensation (Narrative) (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	1,900,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant	561,704
Weighted-average period in years of costs to be recognized	48 months
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized	$ 1.4
Board restricted stock units potentially converted to common stock shares	160,000
Exchange of preferred stock for common stock and common stock warrant			$ 0
Reclassification of stock-based compensation from liability to equity		$ 10.6	7.5
Excess of Capital over Par Value [Member]
Exchange of preferred stock for common stock and common stock warrant			7.5
Reclassification of stock-based compensation from liability to equity		$ 10.6	$ 7.5
Notional Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	0	122,000	252,000	571,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	0	0	0
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period	104,000	128,000	319,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period	(18,000)	(2,000)	0
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value	$ 0	$ 5.53	$ 4.33	$ 3.68
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value	0	0	0
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value	5.53	3.16	0
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value	$ 5.53	$ 5.53	$ 0
Notional Stock Units, Performance Condition [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	8,000	8,000	10,000	0
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	0	0	10,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period	0	0	0
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period	0	(2,000)	0
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value		$ 39.55	$ 39.55	$ 0
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value	$ 0	0	39.55
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value	0	0	0
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value	$ 0	$ 39.55	$ 0
Restricted Stock, Performance Condition [Domain] | 2022 Award
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	17,000	22,000	0
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	0	24,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period	0	0
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period	(5,000)	(2,000)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value	$ 33.70	$ 33.70	$ 0
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value	0	33.70
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value	0	0
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value	$ 33.70	$ 33.70
Restricted Stock, Performance Condition [Domain] | 2023 Award
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	11,000	0
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	17,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period	0
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period	(6,000)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value	$ 42.70	$ 0
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value	42.70
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value	0
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value	$ 42.70

Stock-Based Compensation (Stock

Stock-Based Compensation (Stock-Based Compensation Costs) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Share-Based Payment Arrangement, Noncash Expense [Abstract]
Stock or Unit Option Plan Expense	$ 0	$ 0.1	$ 0.1
Stock Appreciation Rights Expense	1	0.9	11.6
Allocated Share-based Compensation Expense	2.3	1.9	12.2
Share-based Payment Arrangement, Expense, Tax Benefit	(0.3)	(0.2)	(1.5)
Restricted Stock Units (RSUs) [Member]
Share-Based Payment Arrangement, Noncash Expense [Abstract]
Restricted Stock or Unit Expense	0.9	0.7	0.5
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted Stock or Unit Expense	0.9	0.7	0.5
Restricted Stock
Share-Based Payment Arrangement, Noncash Expense [Abstract]
Restricted Stock or Unit Expense	0.4	0.2	0
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted Stock or Unit Expense	$ 0.4	$ 0.2	$ 0

Stock-Based Compensation Stock-

Stock-Based Compensation Stock-Based Compensation (Assumptions Used in the Black-Scholes Option Pricing Model) (Details) - shares	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross	0	0	0
Stock Appreciation Rights (SARs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	0	0	0
Stock Appreciation Rights (SARS), Performance Condition [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	0	0	21,000
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term, Simplified Method			2 years 6 months
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate			0%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate			0.30%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate			82.80%

Stock-Based Compensation Costs,

Stock-Based Compensation Costs, Rollforward (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Number of Exercisable Options	96,000
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Outstanding Options, Weighted Average Exercise Price	$ 4.37	$ 4.37	$ 4.18	$ 4.18
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price	0	0	0
Share-based Compensation Arrangements by Share-based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price	$ 0	$ 4	$ 4.17
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Outstanding Options, Weighted Average Remaining Contractual Term	3 months 18 days	2 years 2 months 12 days	4 years 4 months 24 days	5 years 3 months 18 days
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value	$ 4,800	$ 2,700	$ 8,900	$ 7,800
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value	$ 4,800
Board Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	17,000	28,000	20,000	47,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	17,000	28,000	20,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period	(28,000)	(20,000)	(47,000)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period	0	0	0
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value	$ 35.95	$ 38.80	$ 25.13	$ 10.38
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value	35.95	38.80	25.13
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value	38.80	25.13	10.38
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value	$ 0	$ 0	$ 0
Employee Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	21,000	3,000	4,000	0
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	20,000	0	4,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period	(1,000)	(1,000)	0
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period	(1,000)	0	0
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value	$ 54.04	$ 24.01	$ 24.01	$ 0
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value	55.54	0	24.01
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value	24.01	24.01	0
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value	$ 24.01	$ 0	$ 0
Stock Appreciation Rights (SARs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	0	70,000	84,000	84,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	0	0	0
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period	(74,000)	0	0
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period	4,000	(14,000)	0
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Number of Exercisable Options	0
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Outstanding Options, Weighted Average Exercise Price	$ 0	$ 5.53	$ 5.53	$ 5.53
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price	0	0	0
Share-based Compensation Arrangements by Share-based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price	5.53	0	0
Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures and Expirations in Period, Weighted Average Exercise Price	5.53	$ 5.53	$ 0
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Exercise Price	$ 0
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Outstanding Options, Weighted Average Remaining Contractual Term		3 months 18 days	1 year 3 months 18 days	2 years 3 months 18 days
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value		$ 2,700	$ 3,700	$ 1,500
Stock Appreciation Rights (SARS), Performance Condition [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	17,000	18,000	21,000	0
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	0	0	21,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period	0	0	0
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period	(1,000)	(3,000)	0
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Number of Exercisable Options	17,000
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Outstanding Options, Weighted Average Exercise Price	$ 19.44	$ 19.44	$ 19.44	$ 0
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price	0	0	19.44
Share-based Compensation Arrangements by Share-based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price	0	0	0
Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures and Expirations in Period, Weighted Average Exercise Price	19.44	$ 19.44	$ 0
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Exercise Price	$ 19.44
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Outstanding Options, Weighted Average Remaining Contractual Term	2 months 12 days	1 year 3 months 18 days	2 years 3 months 18 days
Share-based Payment Arrangement, Option, Exercise Price Range, Exercisable, Weighted Average Remaining Contractual Term	2 months 12 days
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value	$ 300	$ 0	$ 600
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value	$ 300
Notional Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	0	122,000	252,000	571,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	0	0	0
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period	(104,000)	(128,000)	(319,000)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period	(18,000)	(2,000)	0
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value	$ 0	$ 5.53	$ 4.33	$ 3.68
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value	0	0	0
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value	5.53	3.16	0
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value	$ 5.53	$ 5.53	$ 0
Notional Stock Units, Performance Condition [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	8,000	8,000	10,000	0
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	0	0	10,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period	0	0	0
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period	0	(2,000)	0
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value		$ 39.55	$ 39.55	$ 0
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value	$ 0	0	39.55
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value	0	0	0
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value	$ 0	$ 39.55	$ 0

Stock-Based Compensation (Optio

Stock-Based Compensation (Options) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Share-Based Payment Arrangement, Noncash Expense [Abstract]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number	96	96	194	411
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Outstanding Options, Weighted Average Exercise Price	$ 4.37	$ 4.37	$ 4.18	$ 4.18
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Outstanding Options, Weighted Average Remaining Contractual Term	3 months 18 days	2 years 2 months 12 days	4 years 4 months 24 days	5 years 3 months 18 days
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross	0	0	0
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price	$ 0	$ 0	$ 0
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period	0	(98)	(217)
Share-based Compensation Arrangements by Share-based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price	$ 0	$ 4	$ 4.17
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value	$ 4.8	$ 2.7	$ 8.9	$ 7.8
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Number of Exercisable Options	96
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Exercisable Options, Weighted Average Exercise Price	$ 4.37
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term	3 months 18 days
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value	$ 4.8

Schedule of Share Based Compens

Schedule of Share Based Compensation Shares Authorized Under Stock Option Plans By Exercise Price (Details) - $ / shares shares in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Outstanding Options, Weighted Average Exercise Price	$ 4.37	$ 4.37	$ 4.18	$ 4.18
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Outstanding Options, Weighted Average Remaining Contractual Term	3 months 18 days	2 years 2 months 12 days	4 years 4 months 24 days	5 years 3 months 18 days
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Number of Exercisable Options	96
Option Group One [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Outstanding Options, Weighted Average Exercise Price	$ 4.37
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Number of Outstanding Options	96
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Outstanding Options, Weighted Average Remaining Contractual Term	3 months 18 days
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Number of Exercisable Options	96

Income Taxes (Details)

Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Dec. 31, 2023	Sep. 30, 2023	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2018
Increase (decrease) in deferred tax asset valuation allowance	$ (11.7)	$ (7.7)
Operating Loss Carryforwards						$ 568
Operating Loss Carryforwards, No Expiration	131.4		$ 131.4
Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance, Amount			31.7	$ 0.6	$ 71.3
Provision (benefit) for income taxes			(0.1)	(15.6)	39.1
Liability for Uncertain Tax Positions, Noncurrent	2.9		2.9	1.9	$ 1
Income Tax Examination, Penalties and Interest Expense Reduction			(0.2)	(0.1)
Unrecognized Tax Benefits, Income Tax Penalties Expense Reduction			(1)	(0.9)
Income Tax Examination, Penalties and Interest Accrued	0.3		$ 0.3	$ 0.1
Federal Statutory Income Tax Rate, Percent			21%	21%	21%
Deferred Tax Assets, Valuation Allowance	382.4		$ 382.4	$ 414.1
Domestic Tax Authority [Member]
Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance, Amount			$ 19.4
State and Local Jurisdiction [Member]
Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Percent			15%	2%	1%
Operating Loss Carryforwards, Valuation Allowance	$ 488.4		$ 488.4
Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance, Amount			$ 12.3	$ 12.1	$ 40.7

Income Taxes (Taxes by Jurisdic

Income Taxes (Taxes by Jurisdiction) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Current Income Tax Expense (Benefit)	$ 1.6	$ 1	$ 0.4
Income Tax Expense (Benefit), Continuing Operations, Adjustment of Deferred Tax (Asset) Liability	1.5	(14.6)	39.5
Provision (benefit) for income taxes	0.1	15.6	(39.1)
Domestic Tax Authority [Member]
Current Income Tax Expense (Benefit)	0	0	0
Income Tax Expense (Benefit), Continuing Operations, Adjustment of Deferred Tax (Asset) Liability	0.7	(14.9)	40.7
State and Local Jurisdiction [Member]
Current Income Tax Expense (Benefit)	1.6	1	0.4
Income Tax Expense (Benefit), Continuing Operations, Adjustment of Deferred Tax (Asset) Liability	0.8	0.3	(1.2)
Foreign Tax Authority [Member]
Current Income Tax Expense (Benefit)	0	0	0
Income Tax Expense (Benefit), Continuing Operations, Adjustment of Deferred Tax (Asset) Liability	$ 0	$ 0	$ 0

Income Taxes (Deferred Income T

Income Taxes (Deferred Income Taxes) (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Components of Deferred Tax Assets and Liabilities [Abstract]
Deferred Tax Assets, Employee Benefits Costs	$ 27.1	$ 33.5
Deferred Tax Assets, Inventory	31.3	21.3
Deferred Tax Assets, Property, Plant and Equipment	178	190.2
Deferred Tax Assets, in Process Research and Development	3.3	3.5
Deferred Tax Assets, Net Operating Loss and Credit Carryforwards	172	188.6
Deferred Tax Assets, Accrued Expenses	0.4	4.9
Deferred Tax Assets, Long-Term Debt and Financing Costs	5.5	7.6
Deferred Tax Asset, Lease Liability	0.8	2.1
Deferred Tax Assets, Other	0.6	0.4
Deferred Tax Assets, Gross	419	452.1
Deferred Tax Assets, Valuation Allowance	(382.4)	(414.1)
Deferred Tax Assets, Net of Valuation Allowance	36.6	38
Deferred Tax Liabilities, Intangible Assets	7.1	9
Deferred Tax Liability, Lease Asset	0.6	1.8
Deferred Tax Liabilities, Prepaid Expenses	0.4	0.4
Deferred Tax Liabilities	8.1	11.2
Deferred Tax Assets, Net, Current	$ 28.5	$ 26.8

Income Taxes (Rate Reconciliati

Income Taxes (Rate Reconciliation) (Details)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Federal Statutory Income Tax Rate, Percent	21%	21%	21%
Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance, Percent	(38.00%)	(1.00%)	(53.00%)
Effective Income Tax Rate Reconciliation, Other Adjustments, Percent	1%	1%	1%
Effective Income Tax Rate Reconciliation, State Income Tax Expense, Net of Federal Benefit, Percent	0%	(1.00%)	1%
Effective Income Tax Rate Reconciliation, Uncertain Tax Positions	1%	1%	0%
Effective Income Tax Rate Reconciliation, Percent	0%	23%	(29.00%)
State and Local Jurisdiction [Member]
Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Percent	15%	2%	1%

Income Taxes (Unrecognized Tax

Income Taxes (Unrecognized Tax Benefits) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Income Tax Disclosure [Abstract]
Liability for Uncertain Tax Positions, Noncurrent	$ 2.9	$ 1.9	$ 1
Unrecognized Tax Benefits, Increase Resulting from Current Period Tax Positions	1	0.9
Unrecognized Tax Benefits, Decrease Resulting from Prior Period Tax Positions	$ 0	$ 0

Net Income Per Share (Narrative

Net Income Per Share (Narrative) (Details) - USD ($) $ / shares in Units, $ in Millions			1 Months Ended		3 Months Ended	12 Months Ended
	Dec. 18, 2023	Dec. 15, 2021	Dec. 31, 2021	Nov. 30, 2021	Dec. 31, 2020	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Sep. 30, 2021	Sep. 30, 2020
Stock Repurchase Price per Share			$ 1,149.99
Preferred Stock, Liquidation Amount per Share			$ 1,291.04					$ 1,291.04		$ 1,347.29
Payments for Repurchase of Preferred Stock and Preference Stock		$ 1.1	$ 43.3	$ 42.2	$ 60	$ 0	$ 0	$ 44.4
Conversion of Stock, Shares Converted						0
Exercise price of warrant	$ 21.62						$ 21.62
Exchange of preferred stock for common stock and common stock warrant								0
Preferred Stock Dividends and Other Adjustments						$ 0		37.6
Aggregate Value, Preferred Stock Transactions								$ 50.8
Common Class A [Member]
Conversion of Stock, Shares Converted	149,179			231,276				231,276
Series B Preferred Stock [Member]
Stock Repurchased and Retired During Period, Shares			980	36,867					62,854
Stock Repurchase Price per Share				$ 1,145.2					$ 954.59
Preferred Stock, Liquidation Amount per Share											$ 1,272.78
Preferred Stock, Par Value Per Share						$ 1
Exchange of preferred stock for common stock and common stock warrant							$ 7.5
Preferred Stock Dividends and Other Adjustments							$ 0
Warrant [Member]
Conversion of Stock, Shares Converted	250,000							250,000
Preferred Series B [Member]
Stock Repurchased and Retired During Period, Shares								37,847
Conversion of Stock, Shares Converted								3,873
Preferred Stock, Liquidation Preference Per Share											$ 1,000

Net Income Per Share (Schedule

Net Income Per Share (Schedule of Income Per Share) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Income Per Share Calculation [Line Items]
Net income	$ 84.4	$ 52.2	$ 175
Preferred stock dividends, undeclared and cumulative	0	0	2.1
Net income (loss) allocable to common stockholders	$ 84.4	$ 50.7	$ 135.3
Average number of shares outstanding, basic	15,212	14,601	13,493
Potentially dilutive shares related to stock options	289	387	386
Average number of shares outstanding, diluted	15,501	14,988	13,879
Net income (loss) per common share - basic	$ 5.55	$ 3.47	$ 10.03
Net income (loss) per common share - diluted	$ 5.44	$ 3.38	$ 9.75
Exchange of preferred stock for common stock and common stock warrant			$ 0
Preferred Stock Dividends and Other Adjustments	$ 0		37.6
Distributed earnings allocable to warrant modification	0	$ 1.5	0
Accumulated Deficit [Member]
Income Per Share Calculation [Line Items]
Net income	84.4	52.2	175
Exchange of preferred stock for common stock and common stock warrant			(7.6)
Distributed earnings allocable to warrant modification	$ 0	$ 1.5	$ 0

Stockholders' Equity (Tables) (

Stockholders' Equity (Tables) (Details) - shares		1 Months Ended	12 Months Ended
	Dec. 18, 2023	Nov. 30, 2021	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Class of Stock [Line Items]
Conversion of Stock, Shares Converted			0
Common Stock, Shares, Issued			15,675,634
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period			0	98,000	217,000
Preferred Series B [Member]
Class of Stock [Line Items]
Conversion of Stock, Shares Converted					(3,873)
Stock Repurchased and Retired During Period, Shares					(37,847)
Preferred Stock, Shares Outstanding			0	0	0	41,720
Common Class A [Member]
Class of Stock [Line Items]
Common Stock, Shares, Outstanding			14,956,434	13,919,646	13,649,933	11,390,189
Conversion of Stock, Shares Converted	(149,179)	(231,276)			(231,276)
Stock Issued During Period, Shares, New Issues			722,568	99,090	1,516,467
Common Stock, Shares, Issued			14,956,434	13,919,646
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period				98,000	216,500
Common Class B [Member]
Class of Stock [Line Items]
Common Stock, Shares, Outstanding			719,200	719,200	719,200	719,200
Common Stock, Shares, Issued			719,200
Restricted Stock Units (RSUs) [Member] | Common Class A [Member]
Class of Stock [Line Items]
Stock Issued During Period, Shares, New Issues			45,437	1,172	89,318
Notional Stock Units [Member] | Common Class A [Member]
Class of Stock [Line Items]
Stock Issued During Period, Shares, New Issues			119,604	71,451	206,183

Stockholders' Equity (Narrative

Stockholders' Equity (Narrative) (Details) - USD ($)			1 Months Ended		3 Months Ended	12 Months Ended
	Dec. 18, 2023	Dec. 15, 2021	Dec. 31, 2021	Nov. 30, 2021	Dec. 31, 2020	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2018	Dec. 31, 2017
Class of Stock [Line Items]
Preferred Stock, Shares Authorized						20,000,000
Preferred Stock, Shares Issued												104,574
Common Stock, Shares, Issued						15,675,634
Conversion of Stock, Shares Converted						0
Preferred Stock Retired, Liquidation Preference								$ 5,000,198
Conversion of Stock, Share Price			21.62					21.62
Class of Warrant or Right, Exercise Price of Warrants or Rights	$ 21.62						$ 21.62
Payments for Repurchase of Preferred Stock and Preference Stock		$ 1,100,000	$ 43,300,000	$ 42,200,000	$ 60,000,000	$ 0	$ 0	$ 44,400,000
Operating Loss Carryforwards											$ 568,000,000
Common Stock Ownership Enabling Preferred Stock Purchase Rights						4.99%
Common Stock Ownership Enabling Preferred Stock Purchase Rights, Incremental						0.50%
Stock issued during period						$ 23,200,000	$ 4,000,000	$ 42,100,000
Stock Repurchase Price per Share			$ 1,149.99
Preferred Stock, Liquidation Amount per Share			$ 1,291.04					$ 1,291.04	$ 1,347.29
Common Class A [Member]
Class of Stock [Line Items]
Common Stock, Shares Authorized						70,000,000
Common Stock, Par or Stated Value Per Share						$ 0.10
Common Stock, Shares, Issued						14,956,434	13,919,646
Stock Issued During Period, Shares, New Issues						722,568	99,090	1,516,467
Stock Issued During Period, Value, Gross						$ 24,400,000	$ 3,800,000	$ 44,200,000
Stock Issued During Period, Value, Net						23,400,000	3,600,000	42,400,000
Direct Costs of Stock Issuance						$ 200,000		$ (300,000)
Conversion of Stock, Shares Converted	149,179			231,276				231,276
Common Class B [Member]
Class of Stock [Line Items]
Common Stock, Shares Authorized						30,000,000
Common Stock, Par or Stated Value Per Share						$ 0.10
Common Stock, Shares, Issued						719,200
Preferred Series B [Member]
Class of Stock [Line Items]
Preferred Stock, Liquidation Preference Per Share										$ 1,000
Preferred stock						$ 0	$ 0
Direct Costs of Stock Issuance								$ 900,000
Conversion of Stock, Shares Converted								3,873
Stock Repurchased and Retired During Period, Shares								37,847
Preferred Stock, Shares Outstanding			0		41,720	0	0	0
Warrant [Member]
Class of Stock [Line Items]
Conversion of Stock, Shares Converted	250,000							250,000

Commitment and Contingencies (D

Commitment and Contingencies (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2023
Loss Contingency, Possible Loss Not Accrued		$ 9.6
Gain (loss) related to litigation settlement	$ 43.5
Pension Plan, Defined Benefit [Member]
Gain (loss) related to litigation settlement	33.8
Other Postretirement Benefits Plan [Member]
Gain (loss) related to litigation settlement	$ 9.7

Revenue by Geographic Area (Det

Revenue by Geographic Area (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Revenue		$ 320.2	$ 293.8	$ 298.3
United States
Revenue		281.6	154.3	220.5
Belgium
Revenue	$ 0.1		38.3	36.6
Japan
Revenue		23.6	61.6	34.6
Other Foreign
Revenue		14.9	39.6	6.6
Foreign [Member]
Revenue		$ 38.6	$ 139.5	$ 77.8

Segment Information (Segment Re

Segment Information (Segment Reporting Information) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Segment Reporting Information [Line Items]
Revenue	$ 320.2	$ 293.8	$ 298.3
Gross Profit	112.1	117.9	114.5
LEU and Technical Solutions Segment
Segment Reporting Information [Line Items]
Revenue	320.2	293.8	298.3
Gross Profit	112.1	117.9	114.5
LEU and Technical Solutions Segment | Intersegment Eliminations
Segment Reporting Information [Line Items]
Revenue	(5)	0	0
Gross Profit	(5)	0	0
Low Enriched Uranium Segment [Member]
Segment Reporting Information [Line Items]
Gross Profit	105.1	130.6	73
Low Enriched Uranium Segment [Member] | Consolidation, Eliminations
Segment Reporting Information [Line Items]
Gross Profit	107.1	130.6	73
Low Enriched Uranium Segment [Member] | Intersegment Eliminations
Segment Reporting Information [Line Items]
Revenue	5	0	0
Gross Profit	2	0	0
Technical Solutions Segment [Member]
Segment Reporting Information [Line Items]
Revenue	325.2	293.8	298.3
Gross Profit	7	(12.7)	41.5
Technical Solutions Segment [Member] | Consolidation, Eliminations
Segment Reporting Information [Line Items]
Gross Profit	10	(12.7)	41.5
Technical Solutions Segment [Member] | Intersegment Eliminations
Segment Reporting Information [Line Items]
Gross Profit	3
Product [Member]
Segment Reporting Information [Line Items]
Revenue	269	235.6	186.1
Product [Member] | Low Enriched Uranium Segment [Member]
Segment Reporting Information [Line Items]
Revenue	274	235.6	186.1
Separative Work Units [Member]
Segment Reporting Information [Line Items]
Revenue	208.2	196.2	163.3
Uranium [Member]
Segment Reporting Information [Line Items]
Revenue	60.8	39.4	22.8
Service [Member] | Technical Solutions Segment [Member]
Segment Reporting Information [Line Items]
Revenue	$ 51.2	$ 58.2	$ 112.2

Segment Information (Narrative)

Segment Information (Narrative) (Details)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Ten Largest Customers | Revenue Benchmark | Customer Concentration Risk
Revenue	79%	75%	57%
Synatom | Revenue Benchmark | Customer Concentration Risk
Revenue	17%	15%	12%
Kyushu Electric Power | Revenue Benchmark | Customer Concentration Risk
Revenue	15%	13%
Energy Harbor Nuclear Corporation | Revenue Benchmark | Customer Concentration Risk
Revenue	13%
Technical Solutions Segment [Member]
Revenue from first customer over 10 percent	16%	20%	38%