Accumulated amortization, intangibles Finite-Lived Intangible Assets, Accumulated Amortization Statistical Measurement [Domain] Statistical Measurement [Domain] Other Current Assets Other Current Assets [Member] Committed Line of Credit Committed Line Of Credit [Member] Committed Line Of Credit [Member] Settled Litigation Settled Litigation [Member] Expected return on plan assets Defined Benefit Plan, Expected Return (Loss) on Plan Assets Total cash flows from discontinued operations Cash Provided by (Used in) Discontinued Operation International Foreign Plan [Member] Award Timing Predetermined Award Timing Predetermined [Flag] Revenue, remaining performance obligation, expected to be satisfied, percentage Revenue, Remaining Performance Obligation, Expected To Be Satisfied, Percentage Revenue, Remaining Performance Obligation, Expected To Be Satisfied, Percentage Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis] Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis] Tax deductible amount Business Combination, Goodwill, Expected Tax Deductible, Amount Entity File Number Entity File Number Letters of Credit Surety Bonds and Bank Guarantees Letters Of Credit Surety Bonds And Bank Guarantees [Member] Letters Of Credit, Surety Bonds And Bank Guarantees [Member] PIC Additional Paid-in Capital [Member] Other Assets Other Noncurrent Assets [Member] Interest Rate Swap Interest Rate Swap [Member] Revenue from performance obligations satisfied in previous periods Contract with Customer, Performance Obligation Satisfied in Previous Period Equity in earnings of unconsolidated affiliates Equity in earnings of unconsolidated affiliates Equity in earnings of unconsolidated affiliates Equity in earnings of unconsolidated affiliates Income (Loss) from Equity Method Investments Tabular List, Table Tabular List [Table Text Block] Income tax (expense) benefit Other Comprehensive Income (Loss), Tax Basic income per share Earnings Per Share, Basic [Abstract] Intangible Asset, Acquired, Finite-Lived [Line Items] Intangible Asset, Acquired, Finite-Lived [Line Items] Recent Accounting Pronouncements New Accounting Pronouncements, Policy [Policy Text Block] Schedule of Services Provided to Unconsolidated JV's Schedule of Related Party Transactions [Table Text Block] Accounts payable Increase (Decrease) in Accounts Payable SOFR Reference Rate Secured Overnight Financing Rate (SOFR) [Member] Schedule of Disposal Groups, Including Discontinued Operations Disposal Groups, Including Discontinued Operations [Table Text Block] Stock options and restricted stock awards Share-Based Payment Arrangement [Member] Value of common stock repurchases Share-Based Payment Arrangement, Decrease for Tax Withholding Obligation Income tax (expense) benefit: Other Comprehensive Income (Loss), Tax [Abstract] Trading Arrangements, by Individual Trading Arrangements, by Individual [Table] Measurement Basis [Axis] Measurement Basis [Axis] Basic earnings per share attributable to KBR (in usd per share) Earnings Per Share, Basic Adjustment to Compensation: Adjustment to Compensation [Axis] United States Government Contract Work [Abstract] United States Government Contract Work [Abstract] United States Government Contract Work [Abstract] Named Executive Officers, Footnote Named Executive Officers, Footnote [Text Block] Liabilities (including current maturities): Liabilities, Fair Value Disclosure [Abstract] Less: Net loss attributable to noncontrolling interests included in discontinued operations Less: Net loss attributable to noncontrolling interests included in discontinued operations Less: Net loss attributable to noncontrolling interests included in discontinued operations Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Noncontrolling Interest Revenue Revenue from Contract with Customer [Text Block] Contractors [Abstract] Contractors [Abstract] Other comprehensive income (loss), net of tax Other comprehensive (loss) income, net of tax Other Comprehensive Income (Loss), Net of Tax Corporate Joint Venture Corporate Joint Venture [Member] Schedule of Operations by Reportable Segment Schedule of Segment Reporting Information, by Segment [Table Text Block] U.S. Government Federal Civilian Clients U.S. Government Federal Civilian Clients [Member] U.S. Government Federal Civilian Clients Schedule of Cash and Cash Equivalents Schedule of Cash and Cash Equivalents [Table Text Block] Debt Instrument, Redemption, Period [Axis] Debt Instrument, Redemption, Period [Axis] Revenue, remaining performance obligation Revenue, Remaining Performance Obligation, Amount Adjustment to Compensation, Amount Adjustment to Compensation Amount Amounts included in project estimates-at-completion at beginning of fiscal year Ending balance of amounts included in project estimates-at-completion Construction Contractor, Contract Cost, Subject to Uncertainty, Amount Pension Plan Pension Plan [Member] Schedule of Carrying Values and Estimated Fair Values of Financial Instruments Fair Value Measurements, Nonrecurring [Table Text Block] Other assets and liabilities Increase (Decrease) in Other Operating Assets Principles of Consolidation Consolidation, Policy [Policy Text Block] Less than 1.25 to 1.00 Consolidated Leverage Ratio, Less than 1.25 to 1.00 [Member] Consolidated Leverage Ratio, Less than 1.25 to 1.00 Employee Stock Option Share-Based Payment Arrangement, Option [Member] Award Timing MNPI Disclosure Award Timing MNPI Disclosure [Text Block] Payment term one Debt Instrument, Payment Term One [Member] Debt Instrument, Payment Term One Variable Interest Entity, Primary Beneficiary Variable Interest Entity, Primary Beneficiary [Member] Litigation settlement amount awarded from other party Litigation Settlement, Amount Awarded from Other Party Antidilutive Securities [Axis] Antidilutive Securities [Axis] Investment in equity method investments, net Investment in (return of) equity method investments, net Payments to Acquire Equity Method Investments Dividends declared to shareholders Dividends, Common Stock, Cash Total KBR shareholders' equity Equity, Attributable to Parent Insider Trading Policies and Procedures [Line Items] Common stock, shares authorized (in shares) Common Stock, Shares Authorized BRIS BRIS [Member] BRIS Current assets: Assets, Current [Abstract] Total liabilities and shareholders' equity Liabilities and Equity Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Accumulated pension liability adjustments Accumulated pension liability adjustments Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member] Schedule of Equity in Earnings of Unconsolidated Affiliates Equity In Earnings of Unconsolidated Affiliates [Table Text Block] [Table Text Block] for Equity In Earnings of Unconsolidated Affiliates [Table] Cash and cash equivalents at beginning of period Cash and cash equivalents at end of period Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Including Discontinued Operation Liabilities and Shareholders' Equity Liabilities and Equity [Abstract] Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items] Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items] Cover [Abstract] Cover [Abstract] Portion at Fair Value Measurement Portion at Fair Value Measurement [Member] Discontinued Operations Spin off Disposal Groups, Including Discontinued Operations, Disclosure [Text Block] Maximum Maximum [Member] Schedule of Equity Method Investments [Table] Equity Method Investment [Table] Purchases of property, plant, and equipment Segment, Expenditure, Addition to Long-Lived Assets April 2025 Forward Interest Rate Swaps April 2025 Forward Interest Rate Swaps [Member] April 2025 Forward Interest Rate Swaps Repayments of secured debt Repayments of Secured Debt Non-PEO NEO Average Total Compensation Amount Non-PEO NEO Average Total Compensation Amount Debt Instrument [Line Items] Debt Instrument [Line Items] Purchases of other investments Purchases of other investments Payments to Acquire Other Investments Treasury Stock Treasury Stock, Common [Member] Net income (loss) from continuing operations Net income from continuing operations Net income from continuing operations Income (Loss) from Continuing Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest Adjustment to Non-PEO NEO Compensation Footnote Adjustment to Non-PEO NEO Compensation Footnote [Text Block] Pay vs Performance Disclosure [Line Items] Accounts payable Disposal Group, Including Discontinued Operation, Accounts Payable, Current Retirement Benefits [Abstract] Retirement Benefits [Abstract] Forgone Recovery due to Disqualification of Tax Benefits, Amount Forgone Recovery due to Disqualification of Tax Benefits, Amount Acquisition Business Combination [Text Block] Non-Rule 10b5-1 Arrangement Terminated Non-Rule 10b5-1 Arrangement Terminated [Flag] Depreciation and amortization Depreciation and amortization Depreciation, Depletion and Amortization, Nonproduction Income (loss) from continuing operations before income taxes Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest Entity Shell Company Entity Shell Company Number of primary areas Number of Primary Areas Number of Primary Areas Other liabilities Other Liabilities, Noncurrent Schedule of Long-term Debt Instruments [Table] Schedule of Long-Term Debt Instruments [Table] Debt Instrument, Redemption, Period [Domain] Debt Instrument, Redemption, Period [Domain] Statement of Stockholders' Equity [Abstract] Statement of Stockholders' Equity [Abstract] Gross loss Disposal Group, Including Discontinued Operation, Gross Profit (Loss) Statement of Cash Flows [Abstract] Statement of Cash Flows [Abstract] Current maturities of long-term debt Less: current portion Long-Term Debt, Current Maturities Company Selected Measure Amount Company Selected Measure Amount Award Timing MNPI Considered Award Timing MNPI Considered [Flag] Line of Credit Facility [Table] Line of Credit Facility [Table] Comprehensive income attributable to KBR Comprehensive Income (Loss), Net of Tax, Attributable to Parent Reclassification out of Accumulated Other Comprehensive Income [Table] Reclassification out of Accumulated Other Comprehensive Income [Table] Share Repurchases Treasury Stock [Text Block] Disposal Group Name [Domain] Disposal Group Name [Domain] Name Measure Name Term Loan B Term Loan B Delayed Draw Term Loan B [Member] Delayed Draw Term Loan B [Member] Net income attributable to KBR from continuing operations Income (Loss) from Continuing Operations, Net of Tax, Attributable to Parent Letter of Credit Letter of Credit [Member] Non-core business segments, number Business Segment, Number of Non-core Business Segments Business Segment, Number of Non-core Business Segments Income tax payable Accrued Income Taxes, Noncurrent Secured Debt Secured Debt [Member] Deferred income taxes Deferred Income Tax Liabilities, Net Document Fiscal Period Focus Document Fiscal Period Focus Net loss attributable to KBR from discontinued operations Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Parent Award Timing Method Award Timing Method [Text Block] Contract Work Activities [Domain] Contract Work Activities [Domain] Contract Work Activities [Domain] Basic earnings per share from continuing operations (in usd per share) Continuing operations (in usd per share) Income (Loss) from Continuing Operations, Per Basic Share Award Type Award Type [Axis] Hedging Relationship [Domain] Hedging Relationship [Domain] Accumulated foreign currency translation adjustments Accumulated Foreign Currency Adjustment Attributable to Parent [Member] Total debt Long-Term Debt Net loss attributable to KBR from discontinued operations: Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Parent [Abstract] Total assets Total assets Assets Investment, Name [Domain] Investment, Name [Domain] International Government Clients International Government [Member] International Government Trading Symbol Trading Symbol Unbilled Retainage [Member] Retainage [Member] Commercial and Infrastructure Clients Commercial and Infrastructure [Member] Commercial and Infrastructure Geographical [Domain] Geographical [Domain] Entity Address, City or Town Entity Address, City or Town Cash flows from operating activities: Cash Provided by (Used in) Operating Activity, Including Discontinued Operation [Abstract] Receivable Type [Axis] Receivable Type [Axis] Term Loan A-2 Delayed Draw Term Loan A-2 [Member] Delayed Draw Term Loan A-2 Effect of exchange rate changes on cash Effect of Exchange Rate on Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Continuing Operation Letters of credit outstanding relate to joint venture operations Letters Of Credit Outstanding Relate To Joint Venture Operations Letters of credit outstanding relate to joint venture operations. Number of active defined benefit plans Defined Contribution Plan, Number Of Active Defined Benefit Plans Defined Contribution Plan, Number Of Active Defined Benefit Plans Non-PEO NEO Average Compensation Actually Paid Amount Non-PEO NEO Average Compensation Actually Paid Amount Compensation Actually Paid vs. Other Measure Compensation Actually Paid vs. Other Measure [Text Block] Purchase price of acquisition Business Combination, Consideration Transferred Damages awarded, value Loss Contingency, Damages Awarded, Value Schedule Of Contract Work Activities [Table] Schedule Of Contract Work Activities [Table] Schedule Of Contract Work Activities [Table] Entity Emerging Growth Company Entity Emerging Growth Company Cash dividends declared per share (in usd per share) Common Stock, Dividends, Per Share, Declared Entity Common Stock, Shares Outstanding (in shares) Entity Common Stock, Shares Outstanding Payments on Revolver Cash repayments on revolver Repayments of Lines of Credit Change in Fair Value as of Vesting Date of Prior Year Equity Awards Vested in Covered Year Change in Fair Value as of Vesting Date of Prior Year Equity Awards Vested in Covered Year [Member] Unamortized debt issuance costs and discounts Debt Issuance Costs, Net Insider Trading Policies and Procedures Not Adopted Insider Trading Policies and Procedures Not Adopted [Text Block] Business Combination [Domain] Business Combination [Domain] Equity Method Investments Equity Method Investments [Member] Common stock, shares outstanding (in shares) Common Stock, Shares, Outstanding Contract liabilities Disposal Group, Including Discontinued Operation, Deferred Revenue, Current PEO PEO [Member] Schedule of Disaggregation of Revenue Disaggregation of Revenue [Table Text Block] Term Loan A-3 Delayed Draw Term Loan A-3 [Member] Delayed Draw Term Loan A-3 Pension assets Assets for Plan Benefits, Defined Benefit Plan United States Domestic U.S UNITED STATES Dividends or Other Earnings Paid on Equity Awards not Otherwise Reflected in Total Compensation for Covered Year Dividends or Other Earnings Paid on Equity Awards not Otherwise Reflected in Total Compensation for Covered Year [Member] Schedule of Unapproved Change Orders and Claims Schedule of Unapproved Claims and Change Orders [Table Text Block] This element may be used to capture the disclosure pertaining to an entity's unapproved claims and change orders used in determining the profit or loss on contracts. Retained Earnings Retained Earnings [Member] Diluted loss per share from discontinued operations (in usd per share) Discontinued operations (in usd per share) Discontinued Operation, Income (Loss) from Discontinued Operation, Net of Tax, Per Diluted Share Effective percentage Debt Instrument, Interest Rate, Effective Percentage Entity Address, Postal Zip Code Entity Address, Postal Zip Code Restatement Determination Date Restatement Determination Date Cash and cash equivalents at end of period for continuing operations Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Continuing Operation Income Statement [Abstract] Income Statement [Abstract] Provision for income taxes Provision for income taxes Tax (benefit) expenses Income Tax Expense (Benefit) Rate Debt Instrument, Basis Spread on Variable Rate Changes in fair value of derivatives Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification, Tax Preferred stock, shares issued (in shares) Preferred Stock, Shares Issued Intangible assets, net of accumulated amortization of $513 and $501, respectively Intangible Assets, Net (Excluding Goodwill) Pension Adjustments Service Cost Pension Adjustments Service Cost [Member] Hedging Relationship [Axis] Hedging Relationship [Axis] Diluted earnings per share from continuing operations (in usd per share) Continuing operations (in usd per share) Income (Loss) from Continuing Operations, Per Diluted Share Net income Net income Net income (loss) Net Income (Loss), Including Portion Attributable to Noncontrolling Interest Restatement does not require Recovery Restatement Does Not Require Recovery [Text Block] Derivative, notional amount Derivative, Notional Amount Discontinued Operations and Disposal Groups [Abstract] Organization, Consolidation and Presentation of Financial Statements [Abstract] Organization, Consolidation and Presentation of Financial Statements [Abstract] Equity Method Investments and Variable Interest Entities Equity Method Investments And Variable Interest Entities [Text Block] Disclosure of variable interest entities (VIE), including, but not limited to the nature, purpose, size, and activities of the VIE, the carrying amount and classification of consolidated assets that are collateral for the VIE's obligations, lack of recourse if creditors (or beneficial interest holders) of a consolidated VIE have no recourse to the general credit of the primary beneficiary. An enterprise that holds a significant variable interest in a VIE but is not the primary beneficiary may disclose the nature of its involvement with the VIE and when that involvement began, the nature, purpose, size, and activities of the VIE and the enterprise's maximum exposure to loss as a result of its involvement with the VIE. Equity Method Investment represents disclosure of information related to equity method investments in common stock. The information which should be considered for disclosure includes: (a) the name of each investee or group of investments for which combined disclosure is appropriate, (2) the percentage ownership of common stock, (3) the difference, if any, between the carrying amount of an investment and the value of the underlying equity in the net assets and the accounting treatment of difference, if any, and (4) the aggregate value of each identified investment based on its quoted market price, if available. Compensation Actually Paid vs. Company Selected Measure Compensation Actually Paid vs. Company Selected Measure [Text Block] March 2020 Interest Rate Swaps March 2020 Interest Rate Swap [Member] March 2020 Interest Rate Swap Unapproved Change Orders and Claims Against Clients Unapproved Claims and Change Orders [Text Block] Unapproved Claims and Change Orders [Text Block] Equity, Class of Treasury Stock [Line Items] Equity, Class of Treasury Stock [Line Items] Debt instrument, covenant, leverage ratio through 2024 and thereafter Debt Instrument, Covenant, Term Three, Leverage Ratio Debt Instrument, Covenant, Term Three, Leverage Ratio Accumulated depreciation, PP&E Property, Plant, and Equipment and Finance Lease Right-of-Use Asset, Accumulated Depreciation and Amortization City Area Code City Area Code Award Timing, How MNPI Considered Award Timing, How MNPI Considered [Text Block] All Trading Arrangements All Trading Arrangements [Member] Equity Awards Adjustments, Footnote Equity Awards Adjustments, Footnote [Text Block] Total Shareholder Return Vs Peer Group Total Shareholder Return Vs Peer Group [Text Block] Redemption price, percentage Debt Instrument, Redemption Price, Percentage Class of Treasury Stock [Table] Class of Treasury Stock [Table] Debt Covenants Terms [Domain] Debt Covenants Terms [Domain] [Domain] for Debt Covenants Terms [Axis] Commitments and Contingencies Disclosure [Abstract] Commitments and Contingencies Disclosure [Abstract] Total investing cash flows from discontinued operations Cash Provided by (Used in) Investing Activity, Discontinued Operation Repurchase of convertible notes Proceeds from Long-Term Lines of Credit Cash flows from investing activities: Cash Provided by (Used in) Investing Activity, Including Discontinued Operation [Abstract] Pay vs Performance Disclosure Pay vs Performance Disclosure [Table] Notes Due 2028 Notes Due 2028 [Member] Notes Due 2028 [Member] Investments in and Advances to Affiliates, at Fair Value [Roll Forward] Investments in and Advances to Affiliates, at Fair Value [Roll Forward] Equity Method Investments and Joint Ventures [Abstract] Equity Method Investments and Joint Ventures [Abstract] Preferred stock, par value (in usd per share) Preferred Stock, Par or Stated Value Per Share Recognized actuarial loss Defined Benefit Plan, Amortization of Gain (Loss) Schedule of Equity Method Investments [Line Items] Schedule of Equity Method Investments [Line Items] Goodwill Goodwill Equity Valuation Assumption Difference, Footnote Equity Valuation Assumption Difference, Footnote [Text Block] Other Equity Method Investment, Other Equity Method Investment, Other PEO Total Compensation Amount PEO Total Compensation Amount Long-term Debt, Type [Axis] Long-Term Debt, Type [Axis] Change of control Debt Instrument, Redemption, Period Three [Member] Equity Components [Axis] Equity Components [Axis] International Non-US [Member] Convertible Senior Notes Convertible Debt [Member] Less than 4.25 to 1.00 but greater than or equal to 3.25 to 1.00 Consolidated Leverage Ratio, Less than 4.25 to 1.00 but greater than or equal to 3.25 to 1.00 [Member] Consolidated Leverage Ratio, Less than 4.25 to 1.00 but greater than or equal to 3.25 to 1.00 Credit spread adjustment Debt Instrument, Basis Spread on Variable Rate Adjustment Debt Instrument, Basis Spread on Variable Rate Adjustment Non-Rule 10b5-1 Arrangement Adopted Non-Rule 10b5-1 Arrangement Adopted [Flag] Trade & other Trade Accounts Receivable [Member] Contract with Customer, Basis of Pricing [Axis] Contract with Customer, Basis of Pricing [Axis] Fair value of interest rate swap assets (liabilities) Interest Rate Derivatives, at Fair Value, Net Supplemental disclosure of cash flows information: Supplemental Cash Flow Information [Abstract] Amortized cost basis Debt Securities, Available-for-Sale, Amortized Cost Revenue from External Customer [Line Items] Revenue from External Customer [Line Items] Other Performance Measure, Amount Other Performance Measure, Amount Entity Address, State or Province Entity Address, State or Province Basic net loss attributable to KBR from discontinued operations Net Income (Loss) from Discontinued Operations Available to Common Shareholders, Basic Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table] Antidilutive Security, Excluded EPS Calculation [Table] Related Party [Domain] Related and Nonrelated Parties [Domain] Total current liabilities Liabilities, Current Other Current Liabilities Other Current Liabilities [Member] Less: Comprehensive loss attributable to noncontrolling interests included in discontinued operations Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest, Discontinued Operations Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest, Discontinued Operations Derivative Instrument [Axis] Derivative Instrument [Axis] Litigation Status [Axis] Litigation Status [Axis] Individual: Individual [Axis] Other countries Other Countries [Member] Other Countries [Member] Number of process technologies (over) Number of Process Technologies Number of Process Technologies Payments of dividends to shareholders Payments of Ordinary Dividends, Common Stock Other current assets Other Assets, Current Equity in and advances to unconsolidated affiliates Beginning balance Ending balance Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures Revenue, remaining performance obligation, expected timing of satisfaction (year) Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period Aggregate Change in Present Value of Accumulated Benefit for All Pension Plans Reported in Summary Compensation Table Aggregate Change in Present Value of Accumulated Benefit for All Pension Plans Reported in Summary Compensation Table [Member] Number of frozen defined benefit plans Defined Contribution Plan, Number Of Frozen Defined Benefit Plans Defined Contribution Plan, Number Of Frozen Defined Benefit Plans Document Fiscal Year Focus Document Fiscal Year Focus Project [Domain] Project [Domain] Operating lease right-of-use assets Operating Lease, Right-of-Use Asset Forgone Recovery, Explanation of Impracticability Forgone Recovery, Explanation of Impracticability [Text Block] Effective income tax rate reconciliation, percent Effective Income Tax Rate Reconciliation, Percent Entity Interactive Data Current Entity Interactive Data Current Carrying Value Reported Value Measurement [Member] Foreign currency translation adjustments Equity Method Investment, Foreign Currency Translation Adjustment Equity Method Investment, Foreign Currency Translation Adjustment Schedule of Sale of Receivables - Third-party Financial Institutions Transfer of Financial Assets Accounted for as Sales [Table Text Block] U.S. Government Defense and Intelligence Clients U.S. Government Defense and Intelligence Clients [Member] U.S. Government Defense and Intelligence Clients Deferred tax assets, valuation allowance Deferred Tax Assets, Valuation Allowance Equity [Abstract] Foreign currency translation adjustments Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, before Tax Settlement of receivables Transfer of Financial Assets Accounted for as Sales, Settlement Of Receivables, Amount Derecognized Transfer of Financial Assets Accounted for as Sales, Settlement Of Receivables, Amount Derecognized Wholly-Owned Captive Insurance Company Wholly-Owned Captive Insurance Company [Member] Wholly-Owned Captive Insurance Company Business Segment Information Segment Reporting Disclosure [Text Block] Quarterly principal payments Debt Instrument, Periodic Payment, Principal Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] Disaggregation of Revenue [Table] Disaggregation of Revenue [Table] Increase (Decrease) in Stockholders' Equity [Roll Forward] Increase (Decrease) in Stockholders' Equity [Roll Forward] Retirement Plan Sponsor Location [Axis] Retirement Plan Sponsor Location [Axis] MTS MTS MTS Mission Technology Solutions [Member] Mission Technology Solutions Schedule of Net Periodic Pension Benefit Schedule of Net Benefit Costs [Table Text Block] Compensation Actually Paid vs. Total Shareholder Return Compensation Actually Paid vs. Total Shareholder Return [Text Block] Contingent consideration Business Combination, Contingent Consideration, Liability Cost of revenues Disposal Group, Including Discontinued Operation, Costs of Goods Sold Fair Value, Recurring and Nonrecurring [Table] Fair Value, Recurring and Nonrecurring [Table] Selling, general and administrative expenses Selling, General and Administrative Expense Receivables sold Proceeds from Sale and Collection of Receivables Deferred income taxes Deferred Income Tax Assets, Net Repurchases of common stock Value of common stock repurchases Stock Repurchased During Period, Value Schedule of Accumulated Other Comprehensive Income (Loss) Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block] Basic net income attributable to KBR from continuing operations Net Income (Loss) from Continuing Operations Available to Common Shareholders, Basic Other assets (including $49 and $0 of available-for-sale debt securities at fair value, respectively) Other Assets, Noncurrent Customer [Domain] Customer [Domain] Entity Central Index Key Entity Central Index Key PEO Name PEO Name Prior Year End Fair Value of Equity Awards Granted in Any Prior Year that Fail to Meet Applicable Vesting Conditions During Covered Year Prior Year End Fair Value of Equity Awards Granted in Any Prior Year that Fail to Meet Applicable Vesting Conditions During Covered Year [Member] Outstanding Aggregate Erroneous Compensation Amount Outstanding Aggregate Erroneous Compensation Amount Fixed Price Fixed-Price Contract [Member] Revolver Revolving Credit Facility [Member] HomeSafe HomeSafe [Member] HomeSafe April 2025 Interest Rate Swaps April 2025 Interest Rate Swaps [Member] April 2025 Interest Rate Swaps Schedule of Defined Benefit Plans Disclosures [Table] Defined Benefit Plan [Table] Abandonment Discontinued Operations, Disposed of by Means Other than Sale, Abandonment [Member] Arrangement Duration Trading Arrangement Duration Schedule of Segment Reporting Information, by Segment [Table] Schedule of Segment Reporting Information, by Segment [Table] Contract liabilities Contract liabilities Contract with Customer, Liability, Current Segments [Axis] Segments [Axis] Sale of receivables Transfer of Financial Assets Accounted for as Sales, Cash Proceeds Received for Assets Derecognized, Amount Exercise Price Award Exercise Price Entity Filer Category Entity Filer Category SONIA Sterling Overnight Index Average (SONIA) [Member] Sterling Overnight Index Average (SONIA) Local Phone Number Local Phone Number Additional 402(v) Disclosure Additional 402(v) Disclosure [Text Block] Europe Europe [Member] Other Payment for (Proceeds from) Other Investing Activity Intangible assets Business Combination, Recognized Asset Acquired, Identifiable Intangible Asset, Excluding Goodwill Cash Business Combination, Recognized Asset Acquired, Cash and Cash Equivalent Payments from unconsolidated affiliates, net Payments for (Proceeds from) Businesses and Interest in Affiliates Assets Assets [Abstract] Long-term debt Total long-term debt, net of current portion Long-Term Debt, Excluding Current Maturities Credit Facility [Axis] Credit Facility [Axis] Underlying Security Market Price Change Underlying Security Market Price Change, Percent Balance Sheet Location [Axis] Statement of Financial Position Location, Balance [Axis] Cash and cash equivalents Disposal Group, Including Discontinued Operation, Cash and Cash Equivalents United States Government Contract Work [Line Items] United States Government Contract Work [Line Items] United States Government Contract Work [Line Items] Debt Instrument [Axis] Debt Instrument [Axis] Fair Value of Financial Instruments and Risk Management Fair Value Disclosures [Text Block] Retirement Benefits Retirement Benefits [Text Block] Balance Sheet Hedge and Operational Exposures Balance Sheet Hedge and Operational Exposures [Member] Balance Sheet Hedge [Member] Credit Facility [Domain] Credit Facility [Domain] KBR shareholders' equity: Equity, Attributable to Parent [Abstract] Vesting Date Fair Value of Equity Awards Granted and Vested in Covered Year Vesting Date Fair Value of Equity Awards Granted and Vested in Covered Year [Member] Loss from discontinued operations before income taxes Discontinued Operation, Income (Loss) from Discontinued Operation During Phase-out Period, before Income Tax Core business segments, number Business Segment, Number of Core Business Segments Business Segment, Number of Core Business Segments Entity Address, Address Line One Entity Address, Address Line One Contract Work Activities [Axis] Contract Work Activities [Axis] Contract Work Activities [Axis] September 2022 Interest Rate Swaps September 2022 Interest Rate Swap [Member] September 2022 Interest Rate Swap AOCL Total AOCI Attributable to Parent [Member] Interest rate, stated percentage Convertible note accrues interest rate Debt Instrument, Interest Rate, Stated Percentage Investment, Name [Axis] Investment, Name [Axis] Allowance for doubtful accounts Accounts Receivable, Allowance for Credit Loss, Current Operating loss Disposal Group, Including Discontinued Operation, Operating Income (Loss) Number of shares (in shares) Share-Based Payment Arrangement, Shares Withheld for Tax Withholding Obligation Operating lease liabilities Operating Lease, Liability, Noncurrent Business Combination, Asset Acquisition, Transaction between Entities under Common Control, and Joint Venture Formation [Abstract] Provision for income taxes Discontinued Operation, Tax Effect of Income (Loss) from Discontinued Operation During Phase-out Period Accrued salaries, wages and benefits Disposal Group, Including Discontinued Operation, Accrued Salaries, Wages And Benefits Disposal Group, Including Discontinued Operation, Accrued Salaries, Wages And Benefits Less than 3.25 to 1.00 but greater than or equal to 2.25 to 1.00 Consolidated Leverage Ratio, Less than 3.25 to 1.00 but greater than or equal to 2.25 to 1.00 [Member] Consolidated Leverage Ratio, Less than 3.25 to 1.00 but greater than or equal to 2.25 to 1.00 Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] Mura Mura Technology [Member] Mura Technology Fair Value as of Grant Date Award Grant Date Fair Value Entity Registrant Name Entity Registrant Name Stock Price or TSR Estimation Method Stock Price or TSR Estimation Method [Text Block] Net periodic pension benefit Defined Benefit Plan, Net Periodic Benefit Cost (Credit) Derivative Instruments and Hedging Activities Disclosures [Table] Derivative Instruments and Hedging Activities Disclosures [Table] Document Quarterly Report Document Quarterly Report Deferred income tax Deferred Income Taxes and Tax Credits Changed Peer Group, Footnote Changed Peer Group, Footnote [Text Block] Counterparty Name [Domain] Counterparty Name [Domain] Carrying value of investment Equity Securities without Readily Determinable Fair Value, Amount Adjustment To PEO Compensation, Footnote Adjustment To PEO Compensation, Footnote [Text Block] Number of Reportable Segments Not Disclosed Flag Number of Reportable Segments Not Disclosed Flag Number of Reportable Segments Not Disclosed Flag Germany GERMANY Schedule of Outstanding Debt Schedule of Debt [Table Text Block] Interest cost Defined Benefit Plan, Interest Cost Related Party, Type [Axis] Related and Nonrelated Parties [Axis] Title Trading Arrangement, Individual Title Peer Group Total Shareholder Return Amount Peer Group Total Shareholder Return Amount Total cash flows provided by operating activities - continuing operations Cash Provided by (Used in) Operating Activity, Continuing Operation Other current liabilities Disposal Group, Including Discontinued Operation, Other Liabilities, Current Other Liabilities Other Noncurrent Liabilities [Member] Restatement Determination Date: Restatement Determination Date [Axis] Cash consideration paid Payments to Acquire Businesses, Gross Share-based compensation Shares Issued, Value, Share-Based Payment Arrangement, after Forfeiture Non-PEO NEO Non-PEO NEO [Member] Letters of credit outstanding Letters of Credit Outstanding, Amount Debt instrument, covenant, leverage ratio through 2023 Debt Instrument, Covenant, Term Two, Leverage Ratio Debt Instrument, Covenant, Term Two, Leverage Ratio Accumulated Other Comprehensive Income (Loss) [Table] Accumulated Other Comprehensive Income (Loss) [Table] Issuance of ESPP shares Stock Issued During Period, Value, Employee Stock Purchase Plan Total cash flows used in investing activities - continuing operations Cash Provided by (Used in) Investing Activity, Continuing Operation Schedule of Interest Rate Swaps Schedule of Interest Rate Derivatives [Table Text Block] Other Proceeds from (Payment for) Other Financing Activity Payments from unconsolidated affiliates, net Collections Repayment Of Advances From To Unconsolidated Affiliates Net Collections Repayment Of Advances From To Unconsolidated Affiliates Net Accumulated Other Comprehensive Income (Loss) [Line Items] Accumulated Other Comprehensive Income (Loss) [Line Items] Amounts reclassified from AOCL Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax Name Trading Arrangement, Individual Name Assets Disposal Group, Including Discontinued Operation, Assets [Abstract] All Award Types Award Type [Domain] Changes in fair value of derivatives Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification, before Tax First Kuwaiti Trading Company Arbitration First Kuwaiti Trading Company Arbitration [Member] First Kuwaiti Trading Company arbitration [Member] Contract with Customer, Basis of Pricing [Domain] Contract with Customer, Basis of Pricing [Domain] Noncontrolling interests Equity, Attributable to Noncontrolling Interest Equity Awards Adjustments Equity Awards Adjustments [Member] Other Other Noncash Income (Expense) Pension Benefits Adjustments, Footnote Pension Benefits Adjustments, Footnote [Text Block] Disaggregation of Revenue [Line Items] Disaggregation of Revenue [Line Items] Defined Benefit Plan Disclosure [Line Items] Defined Benefit Plan Disclosure [Line Items] Compensation Amount Outstanding Recovery Compensation Amount Aggregate principal amount Debt Instrument, Face 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Appreciation Rights (SARs) [Member] Other comprehensive income (loss) Other Comprehensive Income (Loss), before Tax All Executive Categories All Executive Categories [Member] Stockholders' Equity Note [Abstract] Common stock, $0.001 par value 300,000,000 shares authorized, 183,143,531 and 182,891,428 shares issued, and 126,789,905 and 126,454,289 shares outstanding, respectively Common Stock, Value, Issued Commitments and Contingencies Commitments and Contingencies Disclosure [Text Block] Revenues Disposal Group, Including Discontinued Operation, Revenue Uncommitted Line of Credit Uncommitted Line Of Credit [Member] Uncommitted Line Of Credit [Member] Diluted weighted average common shares outstanding (in shares) Weighted Average Number of Shares Outstanding, Diluted Share Repurchase Program 2014 Share Repurchase Program Twenty Fourteen [Member] Share Repurchase Program Twenty Fourteen [Member] Commitments and Contingencies (Notes 5, 10 and 11) Commitments and Contingencies Non-GAAP 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This element may be used as a single block of text to encapsulate the entire disclosure including data and tables. Underlying Securities Award Underlying Securities Amount Term Loan A-1 Delayed Draw Term Loan A-1 [Member] Delayed Draw Term Loan A-1 Payments on short-term and long-term debt Repayments of Other Long-Term Debt Equity Component [Domain] Equity Component [Domain] Document Period End Date Document Period End Date Project [Axis] Project [Axis] PEO Actually Paid Compensation Amount PEO Actually Paid Compensation Amount Cash and Cash Equivalents [Domain] Cash and Cash Equivalents [Domain] Income Taxes Income Tax Disclosure [Text Block] Diluted income per share Earnings Per Share, Diluted [Abstract] Accrued reserve for unallowable costs Accounts Receivable, Allowance for Credit Loss Payment term two Debt Instrument, Payment Term Two [Member] Debt Instrument, Payment Term Two Borrowings on Revolver Proceeds from Lines of Credit Other Privately Held Investments Other Privately Held Investments [Member] Other Privately Held Investments U.K. UNITED KINGDOM Awards Close in Time to MNPI Disclosures, Table Awards Close in Time to MNPI Disclosures [Table Text Block] Revenue from Contract with Customer [Abstract] Revenue from Contract with Customer [Abstract] Schedule of Changes in Fair Value of Balance Sheet Hedges Schedule of Derivatives Instruments Statements of Financial Performance and Financial Position, Location [Table Text Block] Debt instrument, fair value disclosure Debt Instrument, Fair Value Disclosure Total shareholders' equity Beginning balance Ending balance Equity, Including Portion Attributable to Noncontrolling Interest Average price per share (in usd per share) Shares Acquired, Average Cost Per Share Net income attributable to KBR from continuing operations: Income (Loss) from Continuing Operations, Net of Tax, Attributable to Parent [Abstract] Document Type Document Type Income per Share Earnings Per Share [Text Block] Name Outstanding Recovery, Individual Name PIC Additional Paid in Capital Business Combination, Intangible Asset, Acquired, Finite-Lived [Table] Business Combination, Intangible Asset, Acquired, Finite-Lived [Table] Derivative Contract [Domain] Derivative Contract [Domain] Domestic Plan Domestic Plan [Member] Revenues Revenues Total revenue Revenue from Contract with Customer, Excluding Assessed Tax Litigation Status [Domain] Litigation Status [Domain] All Individuals All Individuals [Member] Long-term Debt, Type [Domain] Long-Term Debt, Type [Domain] Fair Value Disclosures [Abstract] Fair Value Disclosures [Abstract] Purchases of property, plant and equipment Payments to Acquire Property, Plant, and Equipment Selling, general and administrative expenses Disposal Group, Including Discontinued Operation, General and Administrative Expense Name Forgone Recovery, Individual Name Cash collected, not yet remitted Transfer Of Financial Assets Accounted For As Sales, Cash Collection, Not Yet Remitted, Amount Derecognized Transfer Of Financial Assets Accounted For As Sales, Cash Collection, Not Yet Remitted, Amount Derecognized Total current assets Assets, Current Statistical Measurement [Axis] Statistical Measurement [Axis] Year-over-Year Change in Fair Value of Equity Awards Granted in Prior Years That are Outstanding and Unvested Year-over-Year Change in Fair Value of Equity Awards Granted in Prior Years That are Outstanding and Unvested [Member] Middle East Middle East [Member] Total operating cash flows from discontinued operations Cash Provided by (Used in) Operating Activity, Discontinued Operation Disposal Group Classification [Axis] Disposal Group Classification [Axis] Reclassification out of Accumulated Other Comprehensive Income Reclassification out of Accumulated Other Comprehensive Income [Member] Stock repurchase program, authorized amount Share Repurchase Program, Authorized, Amount Commitment Fee Line of Credit Facility, Unused Capacity, Commitment Fee Percentage Fixed interest rate Derivative, Fixed Interest Rate Aggregate Erroneous Compensation Amount Aggregate Erroneous Compensation Amount Disposal Group Name [Axis] Disposal Group Name [Axis] Ownership percentage Equity Securities Without Readily Determinable Fair Value, Ownership Percentage Equity Securities Without Readily Determinable Fair Value, Ownership Percentage Peer Group Issuers, Footnote Peer Group Issuers, Footnote [Text Block] Balance Sheet Position - 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Fair Value Gain (Loss) on Fair Value Hedges Recognized in Earnings Recognized actuarial loss Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss) Contract liabilities Increase (Decrease) in Contract with Customer, Liability Other Stockholders' Equity, Other Discontinued operation, ownership percentage in disposed asset Disposal Group, Including Discontinued Operation, Ownership Percentage in Disposed Asset Disposal Group, Including Discontinued Operation, Ownership Percentage in Disposed Asset Cash and Cash Equivalents [Line Items] Cash and Cash Equivalents [Line Items] Debt Instrument, Payment Term [Axis] Debt Instrument, Payment Term [Axis] Debt Instrument, Payment Term Award Timing Disclosures [Line Items] Current assets of discontinued operations Total current assets of discontinued operations Disposal Group, Including Discontinued Operation, Assets, Current Income from domestic sources Effective Income Tax Rate Reconciliation, Tax Contingency, Domestic, Amount Greater than or equal to 4.25 to 1.00 Consolidated Leverage Ratio, Greater than or 4.25 to 1.00 [Member] Consolidated Leverage Ratio, Greater than or 4.25 to 1.00 Long-term debt Long-Term Debt, Gross Accrued salaries, wages and benefits Employee-related Liabilities, Current Subcontractor Settlement Agreement Subcontractor Settlement Agreement [Member] Subcontractor Settlement Agreement Other comprehensive income (loss) adjustments before reclassifications Other Comprehensive Income (Loss), before Reclassifications, Net of Tax Property, plant and equipment, net of accumulated depreciation of $503 and $506 (including net PPE of $5 and $5 owned by a variable interest entity), respectively Net PPE of owned by a variable interest entity Property, Plant, and Equipment and Finance Lease Right-of-Use Asset, after Accumulated Depreciation and Amortization Accumulated Other Comprehensive Loss Equity [Text Block] Distributions to noncontrolling interests Noncontrolling Interest, Decrease from Distributions to Noncontrolling Interest Holders September 2024 Interest Rate Swaps September 2024 Interest Rate Swaps [Member] September 2024 Interest Rate Swaps March 2023 Amortizing Interest Rate Swaps March 2023 Amortizing Interest Rate Swaps [Member] March 2023 Amortizing Interest Rate Swaps Less than 2.25 to 1.00 but greater than or equal to 1.25 to 1.00 Consolidated Leverage Ratio, Less than 2.25 to 1.00 but Greater than to equal to 1.25 to 1.00 [Member] Consolidated Leverage Ratio, Less than 2.25 to 1.00 but Greater than to equal to 1.25 to 1.00 Pension and post-retirement benefits Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, before Tax Net income attributable to KBR Net Income (Loss) Attributable to Parent Expiration Date Trading Arrangement Expiration Date Basic loss per share from discontinued operations (in usd per share) Discontinued operations (in usd per share) Discontinued Operation, Income (Loss) from Discontinued Operation, Net of Tax, Per Basic Share Debt Instrument, Payment Term [Domain] Debt Instrument, Payment Term [Domain] Debt Instrument, Payment Term [Domain] Employee compensation and benefits Noncurrent Employee Compensation And Benefits Aggregate carrying value as of the balance sheet date of the liabilities for all deferred compensation arrangements payable after one year (or the operating cycle, if longer). Represents noncurrent earned compensation under compensation arrangements that is not actually paid until a later date. Segment Reporting Information [Line Items] Segment Reporting Information [Line Items] Preferred stock, shares authorized (in shares) Preferred Stock, Shares Authorized Payments to repurchase common stock Payments for Repurchase of Common Stock Adoption Date Trading Arrangement Adoption Date Maximum contingent consideration Business Combination, Contingent Consideration, Range of Outcomes, Maximum, Amount Base Rate Base Rate [Member] Term Loan A Term Loan A Delayed Draw Term Loan A [Member] Delayed Draw Term Loan A [Member] Compensation Actually Paid vs. Net Income Compensation Actually Paid vs. Net Income [Text Block] Accounts receivable, net of allowance for credit losses Increase (Decrease) in Accounts Receivable Net gain (loss) Gain (Loss) on Foreign Currency Fair Value Hedge Derivatives Contract assets Contract with Customer, Asset, after Allowance for Credit Loss Asia Asia [Member] Entity Current Reporting Status Entity Current Reporting Status Customer [Axis] Customer [Axis] Awards Close in Time to MNPI Disclosures Awards Close in Time to MNPI Disclosures [Table] Revenue from External Customers by Products and Services [Table] Segment Reporting, Revenue from External Customer, Product and Service [Table] Customer relationships Customer Relationships [Member] Operating income Operating income Operating Income (Loss) Revolver Revolver Line of Credit [Member] Consolidated Entities [Domain] Consolidated Entities [Domain] Retained earnings Retained Earnings (Accumulated Deficit) Schedule of Shares Repurchased Class of Treasury Stock [Table Text Block] Corporate Corporate Segment [Member] Financial Instrument [Axis] Financial Instrument [Axis] Statement of Financial Position [Abstract] Statement of Financial Position [Abstract] Year-end Fair Value of Equity Awards Granted in Covered Year that are Outstanding and Unvested Year-end Fair Value of Equity Awards Granted in Covered Year that are Outstanding and Unvested [Member] Executive Category: Executive Category [Axis] Other Other Operating Income (Expense), Net Current Fiscal Year End Date Current Fiscal Year End Date Changes in fair value of derivatives Changes in fair value for derivatives Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent [Member] Changes in operating assets and liabilities: Increase (Decrease) in Other Operating Assets and Liabilities, Net [Abstract] Finite-Lived Intangible Assets, Major Class Name [Domain] Finite-Lived Intangible Assets, Major Class Name [Domain] Unapproved Change Orders [Roll Forward] Unapproved Change Orders [Roll Forward] unapproved Change Orders [Roll Forward] Aggregate Grant Date Fair Value of Equity Award Amounts Reported in Summary Compensation Table Aggregate Grant Date Fair Value of Equity Award Amounts Reported in Summary Compensation Table [Member] Current liabilities of discontinued operations Total current liabilities of discontinued operations Disposal Group, Including Discontinued Operation, Liabilities, Current Retirement Plan Type [Axis] Retirement Plan Type [Axis] Schedule of Accounts Receivable Schedule of Accounts, Notes, Loans and Financing Receivable [Table Text Block] Statement [Table] Statement [Table] Other non-operating income Other non-operating income (expense) Other Nonoperating Income (Expense) Adjustments to reconcile net income to net cash provided by operating activities: Adjustment to Reconcile Net Income to Cash Provided by (Used in) Operating Activity [Abstract] Cash flows from financing activities: Cash Provided by (Used in) Financing Activity, Including Discontinued Operation [Abstract] Reclassification out of Accumulated Other Comprehensive Income [Domain] Reclassification out of Accumulated Other Comprehensive Income [Domain] Cash and cash equivalents Cash [Member] Equity Awards Adjustments, Excluding Value Reported in Compensation Table Equity Awards Adjustments, Excluding Value Reported in the Compensation Table [Member] Less: Net income attributable to noncontrolling interests included in continuing operations Less: Net income attributable to noncontrolling interests included in continuing operations Less: Net income attributable to noncontrolling interests included in continuing operations Income (Loss) from Continuing Operations, Net of Tax, Attributable to Noncontrolling Interest Variable Rate [Domain] Variable Rate [Domain] Distributions of earnings from unconsolidated affiliates Distributions of earnings of unconsolidated affiliates Proceeds from Equity Method Investment, Distribution Amounts recognized over time based on progress Construction Contractor, Contract Cost, Amounts Recognized, Amount Construction Contractor, Contract Cost, Amounts Recognized, Amount Basis of Presentation Organization, Consolidation and Presentation of Financial Statements Disclosure [Text Block] Additional amount authorized for repurchase program Stock Repurchase Program, Increase In Authorized Amount Stock Repurchase Program, Increase In Authorized Amount Cash and Cash Equivalents [Abstract] Cash and Cash Equivalents [Abstract] Transfer of Financial Assets Accounted for as Sales [Roll Forward] Transfer of Financial Assets Accounted for as Sales [Roll Forward] Transfer of Financial Assets Accounted for as Sales Antidilutive securities excluded from computation of earnings per share, amount (in shares) Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount Weighted average common shares outstanding: Weighted Average Number of Shares Outstanding, Diluted [Abstract] All Adjustments to Compensation All Adjustments to Compensation [Member] Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Table] Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Table] Amendment Flag Amendment Flag Infrastar Corporation Infrastar Corporation [Member] Infrastar Corporation Treasury stock, 56,353,626 shares and 56,437,139 shares, at cost, respectively Treasury Stock, Common, Value Termination Date Trading Arrangement Termination Date Total cash flows used in financing activities - continuing operations Cash Provided by (Used in) Financing Activity, Including Discontinued Operation Contract assets Increase (Decrease) in Contract with Customer, Asset Insider Trading Policies and Procedures Adopted Insider Trading Policies and Procedures Adopted [Flag] Measure: Measure [Axis] Liabilities for uncertain tax positions Liability for Uncertainty in Income Taxes, Noncurrent Receivable [Domain] Receivable [Domain] Schedule of Managing of Risks Inherent in Servicing Assets and Servicing Liabilities [Table] Servicing Asset and Servicing Liability, Risk Mitigation [Table] Available-for-sale debt securities at fair value Debt securities other asset at fair value Debt Securities, Available-for-Sale, Noncurrent Basic weighted average common shares outstanding (in shares) Weighted Average Number of Shares Outstanding, Basic Remaining authorized repurchase amount Share Repurchase Program, Remaining 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Rate Swap [Member] March 2023 Interest Rate Swap Dividends declared Dividends Payable, Current Net increase in project estimates Unapproved Change Orders, Increase (Decrease) In Estimates Unapproved Change Orders, Increase (Decrease) In Estimates Interest expense Interest rate swap settlements Interest Expense, Nonoperating Trading Arrangement: Trading Arrangement [Axis] Total Shareholder Return Amount Total Shareholder Return Amount Accounts receivable, net of allowance for credit losses of $5 and $6, respectively Accounts receivable, net Accounts receivable, net of allowance for credit losses Accounts and Financing Receivable, after Allowance for Credit Loss, Current Insider Trading Arrangements [Line Items] Maximum length of time hedged in balance sheet hedge and operational exposures Maximum Length of Time Hedged in Balance Sheet Hedge and Operational Exposures Maximum Length of Time Hedged in Balance Sheet Hedge and Operational Exposures Security Exchange Name Security Exchange 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