Lease Maturities [Abstract] Lease Maturities [Abstract] Statement [Table] Statement [Table] Statistical Measurement [Axis] Range Statistical Measurement [Domain] Minimum Minimum [Member] Maximum [Member] Maximum [Member] Statement [Line Items] Statement [Line Items] Lessee, Operating Lease, Lease Not yet Commenced, Value Lessee, Operating Lease, Lease Not yet Commenced, Value Lessee, Operating Lease, Lease Not yet Commenced, Value Lessee, Operating Lease, Lease Not yet Commenced, Term of Contract Lessee, Operating Lease, Lease Not yet Commenced, Term of Contract Lessee, Operating Lease, Liability, Payments, Due Next Year Lessee, Operating Lease, Liability, Payments, Due Next Twelve Months Lessee, Operating Lease, Liability, Payments, Due Year Two Lessee, Operating Lease, Liability, Payments, Due Year Two Lessee, Operating Lease, Liability, Payments, Due Year Three Lessee, Operating Lease, Liability, Payments, Due Year Three Lessee, Operating Lease, Liability, Payments, Due Year Four Lessee, Operating Lease, Liability, Payments, Due Year Four Lessee, Operating Lease, Liability, Payments, Due Year Five Lessee, Operating Lease, Liability, Payments, Due Year Five Lessee, Operating Lease, Liability, Payments, Due after Year Five Lessee, Operating Lease, Liability, Payments, Due after Year Five Lessee, Operating Lease, Liability, Payments, Due Lessee, Operating Lease, Liability, Payments, Due Lessee, Operating Lease, Liability, Undiscounted Excess Amount Lessee, Operating Lease, Liability, Undiscounted Excess Amount Operating Lease, Liability Operating Lease, Liability Segment Reporting [Abstract] Sales and operating income by segment Reconciliation of Operating Profit (Loss) from Segments to Consolidated [Table Text Block] Schedule of Revenue by Major Customers by Reporting Segments [Table Text Block] Schedule of Revenue by Major Customers by Reporting Segments [Table Text Block] Reconciliation of Revenue from Segments to Consolidated [Table Text Block] Reconciliation of Revenue from Segments to Consolidated [Table Text Block] Revenue from External Customers by Geographic Areas [Table Text Block] Revenue from External Customers by Geographic Areas [Table Text Block] Intersegment sales and operating income Segment Reporting Information Intersegment Sales And Operating Income [Table Text Block] Tabular disclosure of segment reporting information intersegment sales and operating income. Total assets by segment Reconciliation of Assets from Segment to Consolidated [Table Text Block] Additional information by segment Reconciliation of Other Significant Reconciling Items from Segments to Consolidated [Table Text Block] Income Tax Disclosure [Abstract] Components of Deferred Tax Assets and Liabilities (Table Amounts) [Abstract] Components of Deferred Tax Assets and Liabilities [Abstract] Deferred Tax Assets (Table Amounts) Components of Deferred Tax Assets [Abstract] Retiree benefits Deferred Tax Assets, Tax Deferred Expense, Compensation and Benefits, Postretirement Benefits Accrued employee compensation Deferred Tax Assets, Tax Deferred Expense, Compensation and Benefits, Employee Compensation Provisions for accrued liabilities Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals, Accrued Liabilities Inventory Deferred Tax Assets, Inventory Stock-based compensation Deferred Tax Assets, Tax Deferred Expense, Compensation and Benefits, Share-based Compensation Cost Operating lease liabilities Deferred Tax Asset Lease Liabilities Deferred Tax Asset Lease Liabilities Tax credits Deferred Tax Assets, Tax Credit Carryforwards Other Deferred Tax Assets, Other Gross deferred tax assets Deferred Tax Assets, Gross Less valuation allowance Deferred Tax Assets, Valuation Allowance Net deferred tax assets Deferred Tax Assets, Net of Valuation Allowance Deferred Tax Liabilities (Table Amounts) Components of Deferred Tax Liabilities [Abstract] Goodwill Deferred Tax Liabilities, Goodwill Purchased intangibles Deferred Tax Liabilities, Purchase Intangibles Deferred Tax Liabilities, Purchase Intangibles Property, plant and equipment, net Deferred Tax Liabilities, Property, Plant and Equipment Operating lease right-of-use assets Deferred Tax Liabilities, Leasing Arrangements Contract accounting differences Deferred Tax Liabilities, Tax Deferred Income Other Deferred Tax Liabilities, Other Deferred tax liabilities Deferred Tax Liabilities, Gross Total net deferred tax assets (liabilities) Deferred Tax Liabilities, Net Total net deferred tax assets (liabilities) Deferred Tax Assets, Net Effective Income Tax Reconciliation, change in enacted tax rate due to 2017 Tax Act, amount Effective Income Tax Reconciliation, change in enacted tax rate due to 2017 Tax Act, amount Effective Income Tax Reconciliation, change in enacted tax rate due to 2017 Tax Act, amount Effective income tax rate Effective Income Tax Rate Reconciliation, Percent Significant matters affecting comparability Significant matters affecting effective tax rate comparability, percent 740-10-50-14. If not otherwise evident from the disclosures required by this Section, all entities shall disclose the nature and effect of any other significant matters affecting comparability of information for all periods presented. Increase in Research Tax Credit Effective Income Tax Rate Reconciliation, Increase in Research Tax Credits Effective Income Tax Rate Reconciliation, Increase in Research Tax Credits Increase in Foreign Derived Intangible Income Effective Tax Rate Reconciliation, Increase in Foreign Derived Intangible Income Effective Tax Rate Reconciliation, Increase in Foreign Derived Intangible Income Effective Income Tax Rate Reconciliation, Tax Cuts and Jobs Act, Amount Effective Income Tax Rate Reconciliation, Tax Cuts and Jobs Act, Amount Effective Income Tax Rate Reconciliation, Deduction, Qualified Production Activity, Amount Effective Income Tax Rate Reconciliation, Deduction, Qualified Production Activity, Amount Effective Tax Rate Reconciliation, Mark-to-Market benefit tax rate differential, amount Effective Tax Rate Reconciliation, Mark-to-Market benefit tax rate differential, amount Effective Tax Rate Reconciliation, Mark-to-Market benefit tax rate differential, amount Income taxes paid, net Income Taxes Paid, Net Tax Credit Carryforward, Amount Tax Credit Carryforward, Amount Operating Loss Carryforwards Operating Loss Carryforwards Tax Credit Carryforward, Valuation Allowance Tax Credit Carryforward, Valuation Allowance Operating Loss Carryforwards, Valuation Allowance Operating Loss Carryforwards, Valuation Allowance Retirement Benefits [Abstract] Schedule of Defined Benefit Plans Disclosures [Table] Schedule of Defined Benefit Plans Disclosures [Table] Retirement Plan Type [Axis] Retirement Plan Type [Axis] Retirement Plan Type [Domain] Retirement Plan Type [Domain] Pension Benefits Pension Plan [Member] Medical and Life Benefits Other Postretirement Benefits Plan [Member] Defined Benefit Plan Disclosure (Table Amounts) Defined Benefit Plan Disclosure [Line Items] Estimated Benefit Payments (Table Amounts) [Abstract] Defined Benefit Plan, Expected Future Benefit Payment [Abstract] 2020 Defined Benefit Plan, Expected Future Benefit Payment, Next Twelve Months 2021 Defined Benefit Plan, Expected Future Benefit Payment, Year Two 2022 Defined Benefit Plan, Expected Future Benefit Payment, Year Three 2023 Defined Benefit Plan, Expected Future Benefit Payment, Year Four 2024 Defined Benefit Plan, Expected Future Benefit Payment, Year Five 2025 through 2029 Defined Benefit Plan, Expected Future Benefit Payment, Five Fiscal Years Thereafter Pension and Other Post-retirement benefit plans [Member] Pension and Other Post-retirement benefit plans [Member] Pension and Other Post-retirement benefit plans. Plan Assets by Fair Value Measurement Input [Axis] Fair Value Hierarchy and NAV [Axis] Fair Value Hierarchy and NAV [Domain] Fair Value Hierarchy and NAV [Domain] Level 1 Fair Value, Inputs, Level 1 [Member] Level 2 Fair Value, Inputs, Level 2 [Member] Level 3 Fair Value, Inputs, Level 3 [Member] Plan Assets Disclosures, Major Asset Classes [Axis] Defined Benefit Plan, Plan Assets, Category [Axis] Plan Assets, Major Asset Categories [Domain] Defined Benefit Plan, Plan Assets, Category [Domain] Cash & cash equivalents Cash and Cash Equivalents [Member] U.S. Equity Securities [Member] U.S. Equity Securities [Member] The ownership interests or the right to acquire ownership interests in corporations and other legal entities based in the United States which ownership interest is represented by shares of common or preferred stock (which is neither mandatorily redeemable no redeemable at the option of the holder), convertible securities, stock rights, or stock warrants. International equities International Equity Securities [Member] The ownership interests or the right to acquire ownership interests in corporations and other legal entities not based in the United States which ownership interest is represented by shares of common or preferred stock (which is neither mandatorily redeemable nor redeemable at the option of the holder), convertible securities, stock rights, or stock warrants. Fixed income securities Fixed Income Securities [Member] U.S. Treasuries US Treasury Securities [Member] U.S. Government Agency US Government Agencies Debt Securities [Member] Non-U.S. Government Debt Security, Government, Non-US [Member] Corporate debt Corporate Debt Securities [Member] Asset backed Asset-backed Securities [Member] High yield debt High Yield Debt Securities [Member] This category includes information about firm holdings in high-yield fixed income or other debt securities issued by a corporation or other issuer. Bank loans Bank Loans [Member] This category includes information about firm holdings in borrowings from a bank. Other Other Asset Categories [Member] Other holdings. Fixed Income Funds Fixed Income Funds [Member] Hedge Funds Hedge Funds [Member] OpportunisticFunds OpportunisticFunds [Member] Investments in a broad range of primarily private investment funds, including illiquid credit investments. Private Equity Funds [Member] Private Equity Funds [Member] Real Estate Funds [Member] Real Estate Funds [Member] Plan Assets by Fair Value Measurement Input (Table Amounts) [Abstract] Defined Benefit Plan, Information about Plan Assets [Abstract] Fair value of plan assets Defined Benefit Plan, Plan Assets, Amount Alternative Investment, Net Asset Value Alternative Investment Derivative Asset Derivative Asset Derivative Liability Derivative Liability Derivative, Notional Amount Derivative, Notional Amount Quarterly Financial Information Disclosure [Abstract] Quarterly Financial Information [Table Text Block] Quarterly Financial Information [Table Text Block] Income Statement [Abstract] Product and Service [Axis] Product and Service [Axis] Product and Service [Domain] Product and Service [Domain] Product [Member] Product [Member] Service [Member] Service [Member] Cost of Goods and Services Sold Cost of Goods and Services Sold Revenues Revenues Operating costs and expenses Cost of Goods and Services Sold [Abstract] General and administrative expenses General and Administrative Expense Operating income Operating Income (Loss) Other (expense) income Other Nonoperating Income (Expense) [Abstract] Interest expense Interest and Debt Expense FAS (non-service) pension benefit Net FAS (non-service) Pension Benefit (Expense) Net FAS (non-service) Pension Benefit (Expense) Mark-to-market pension and OPB (expense) benefit Defined Benefit Plan, Actuarial Gain (Loss), Immediate Recognition as Component in Net Periodic Benefit (Cost) Credit Other, net Other Nonoperating Income (Expense) Earnings before income taxes Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest Federal and foreign income tax expense Income Tax Expense (Benefit) Net earnings Net Income (Loss) Attributable to Parent Basic earnings per share Earnings Per Share, Basic [Abstract] Basic earnings per share Earnings Per Share, Basic Weighted-average common shares outstanding, in millions Weighted Average Number of Shares Outstanding, Basic Diluted earnings per share Earnings Per Share, Diluted [Abstract] Diluted earnings per share Earnings Per Share, Diluted Weighted-average diluted shares outstanding, in millions Weighted Average Number of Shares Outstanding, Diluted Net earnings (from above) Other comprehensive loss Other Comprehensive Income (Loss), Net of Tax [Abstract] Change in unamortized prior service credit, net of tax expense of $15 in 2019, $19 in 2018 and $35 in 2017 Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, after Tax Change in cumulative translation adjustment and other, net Other Comprehensive Income (Loss), Foreign Currency Translation and Translation Adjustment and Other, Net of Tax Other Comprehensive Income (Loss), Foreign Currency Translation and Translation Adjustment and Other, Net of Tax Other comprehensive loss, net of tax Other Comprehensive Income (Loss), Net of Tax Comprehensive income Comprehensive Income (Loss), Net of Tax, Attributable to Parent Organization, Consolidation and Presentation of Financial Statements [Abstract] Accumulated Other Comprehensive Loss Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract] Unamortized prior service credit, net of tax expense of $17 for 2019 and $32 for 2018 Accumulated Other Comprehensive (Income) Loss, Defined Benefit Plan, after Tax Cumulative translation adjustment Accumulated Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Net of Tax Other, net Accumulated Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax And Accumulated Other Comprehensive Income Loss Cumulative Changes In Net Gain Loss From Cash Flow Hedges Effect Net Of Tax The accumulated appreciation or loss, net of tax, in value of the total of unsold securities at the end of an accounting period and the accumulated change, net of tax, in accumulated gains and losses from derivative instruments designated and qualifying as the effective portion of cash flow hedges. Includes an entity's share of an equity investee's increase (decrease) in deferred hedging gains or losses. Total accumulated other comprehensive loss Accumulated Other Comprehensive Income (Loss), Net of Tax Unamortized benefit plan costs - Tax Benefit Unamortized benefit plan costs - Tax Benefit (expense) Amount of tax benefit (expense) related to the ending balance of unamortized benefit plan costs in accumulated other comprehensive income. Unbilled Receivables, Net [Abstract] Unbilled Receivables, Net [Abstract] Unbilled receivables Schedule of Unbilled Receivables [Table Text Block] Schedule of Unbilled Receivables [Table Text Block] Earnings Per Share [Abstract] Share Repurchases Class of Treasury Stock [Table Text Block] Unrecognized Tax Benefits, Increase Resulting from 2017 Tax Act Unrecognized Tax Benefits, Increase resulting from 2017 Tax Act Unrecognized Tax Benefits, Increase resulting from 2017 Tax Act Decrease in Unrecognized Tax Benefits is Reasonably Possible Decrease in Unrecognized Tax Benefits is Reasonably Possible Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued Unrecognized Tax Benefits that Would Impact Effective Tax Rate Unrecognized Tax Benefits that Would Impact Effective Tax Rate Unrecognized Tax Benefits Rollforward (Table Amounts) [Abstract] Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward] Unrecognized tax benefits at beginning of the year Unrecognized Tax Benefits Additions based on tax positions related to the current year Unrecognized Tax Benefits, Increase Resulting from Current Period Tax Positions Additions for tax positions of prior years Unrecognized Tax Benefits, Increase Resulting from Prior Period Tax Positions Reductions for tax positions of prior years Unrecognized Tax Benefits, Decrease Resulting from Prior Period Tax Positions Settlements with taxing authorities Unrecognized Tax Benefits, Decrease Resulting from Settlements with Taxing Authorities Other, net UnrecognizedTaxBenefitsOther Unrecognized Tax Benefits, Other Net change in unrecognized tax benefits Unrecognized Tax Benefits, Period Increase (Decrease) Unrecognized tax benefits at end of the year Leases [Abstract] Lessee, Operating Leases [Text Block] Lessee, Operating Leases [Text Block] Debt Disclosure [Abstract] Maturities of Long-term Debt [Abstract] Maturities of Long-term Debt [Abstract] 2020 Long-term Debt, Maturities, Repayments of Principal in Next Twelve Months 2021 Long-term Debt, Maturities, Repayments of Principal in Year Two 2022 Long-term Debt, Maturities, Repayments of Principal in Year Three 2023 Long-term Debt, Maturities, Repayments of Principal in Year Four 2024 Long-term Debt, Maturities, Repayments of Principal in Year Five Thereafter Long-term Debt, Maturities, Repayments of Principal after Year Five Total principal payments Long-term Debt, Gross Unamortized premium on long-term debt, net of discount Debt Instrument, Unamortized Discount (Premium), Net Debt issuance costs Debt Issuance Costs, Net Total long-term debt Long-term Debt Goodwill and Intangible Assets Disclosure [Abstract] 2020 Finite-Lived Intangible Assets, Amortization Expense, Next Twelve Months 2021 Finite-Lived Intangible Assets, Amortization Expense, Year Two 2022 Finite-Lived Intangible Assets, Amortization Expense, Year Three 2023 Finite-Lived Intangible Assets, Amortization Expense, Year Four 2024 Finite-Lived Intangible Assets, Amortization Expense, Year Five Lease, Cost [Table Text Block] Lease, Cost [Table Text Block] Supplemental Balance Sheet Disclosures [Text Block] Supplemental Balance Sheet Disclosures [Text Block] Other Supplemental Lease Information [Table Text Block] Other Supplemental Lease Information [Table Text Block] Other Supplemental Lease Information [Table Text Block] Lessee, Operating Lease, Liability, Maturity [Table Text Block] Lessee, Operating Lease, Liability, Maturity [Table Text Block] Schedule of Future Minimum Rental Payments for Operating Leases [Table Text Block] Schedule of Future Minimum Rental Payments for Operating Leases [Table Text Block] Inventory Disclosure [Abstract] Production costs of contracts in process Inventory, Work in Process, Net of Reserves General and administrative expenses Inventory for Long-term Contracts or Programs, General and Administrative Costs Included in Inventory Inventoried costs Inventory, Finished Goods and Work in Process, Net of Reserves Progress and performance-based payments received Progress Payments Netted Against Inventory for Long-term Contracts or Programs Inventoried costs, net of progress payments Inventoried Costs Net Of Progress Payments Carrying amount (lower of cost or market) of inventories less all valuation, other allowances, and progress payments or customer advances received on long-term contracts or programs. Excludes noncurrent inventory balances (expected to remain on hand past one year or one operating cycle, if longer). Product inventory Other Inventory, Net of Reserves Inventory, Net Inventory, Net Benefit Obligation [Member] Benefit Obligation [Member] Post-retirement benefit obligation. Post-retirement Benefit Cost [Member] Post-retirement Benefit Cost [Member] Post-retirement benefit cost. Defined Benefit Plan Disclosure (Table Amounts) Initial health care cost trend rate assumed for the next year Defined Benefit Plan, Health Care Cost Trend Rate Assumed, Next Fiscal Year Rate to which the health care cost trend rate is assumed to decline (the ultimate trend rate) Defined Benefit Plan, Ultimate Health Care Cost Trend Rate Year that the health care cost trend rate reaches the ultimate trend rate Defined Benefit Plan, Year Health Care Cost Trend Rate Reaches Ultimate Trend Rate Assumptions Used to Determine Benefit Obligation Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract] Discount rate Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate Initial cash balance crediting rate assumed for the next year Defined Benefit Plan, Benefit Obligation, Cash Balance Crediting Rate Assumed for Next Fiscal Year Cash Balance Crediting Rate Assumed for Next Fiscal Year used to calculate the benefit obligation. Rate to which the cash balance crediting rate is assumed to increase (the ultimate rate) Defined Benefit Plan, Benefit Obligation, Ultimate Cash Balance Crediting Rate Defined Benefit Plan Ultimate Cash Balance Crediting Rate used to calculate the benefit obligation Year that the cash balance crediting rate reaches the ultimate rate Defined Benefit Plan, Benefit Obligation, Cash Balance Crediting Rate, Year that rate reaches ultimate rate Defined Benefit Plan, Cash Balance Crediting Rate, Year that rate reaches ultimate rate, used to calculate benefit obligation, in CCYY format. Rate of compensation increase Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Rate of Compensation Increase Assumptions Used to Determine Benefit Cost Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract] Discount rate Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Discount Rate Initial cash balance crediting rate assumed for the next year Defined Benefit Plan, Benefit Cost, Cash Balance Crediting Rate Assumed for next fiscal year Cash Balance Crediting Rate Assumed for next fiscal year used to calculate benefit cost Rate to which the cash balance crediting rate is assumed to increase (the ultimate rate) Defined Benefit Plan, Benefit Cost, Ultimate Cash Balance Crediting Rate Defined Benefit Plan Ultimate Cash Balance Crediting Rate, used to calculate benefit cost Year that the cash balance crediting rate reaches the ultimate rate Defined Benefit Plan, Benefit Cost, Cash Balance Crediting Rate, Year that the rate reaches the ultimate rate Defined Benefit Plan, Cash Balance Crediting Rate, Year that the rate reaches the ultimate rate, used to calculate benefit cost. Expected long-term return on plan assets Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Expected Long-term Rate of Return on Plan Assets Rate of compensation increase Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Rate of Compensation Increase Fair Value Disclosures [Abstract] Foreign Currency Derivative Instruments Not Designated as Hedging Instruments, Asset at Fair Value Foreign Currency Derivative Instruments Not Designated as Hedging Instruments, Asset at Fair Value Foreign Currency Cash Flow Hedge Derivative at Fair Value, Net Foreign Currency Cash Flow Hedge Derivative at Fair Value, Net Schedule of Accounts, Notes, Loans and Financing Receivable [Table] Schedule of Accounts, Notes, Loans and Financing Receivable [Table] Legal Entity of Counterparty, Type [Axis] Legal Entity of Counterparty, Type [Axis] Legal Entity Type of Counterparty [Domain] Legal Entity Type of Counterparty [Domain] US Government [Member] US Government [Member] US Government [Member] International and Other Customers [Member] International and Other Customers [Member] International and Other customers. Accounts, Notes, Loans and Financing Receivable [Line Items] Accounts, Notes, Loans and Financing Receivable [Line Items] Unbilled receivables Unbilled Contracts Receivable Government Contract Receivable, Progress Payment Offset Government Contract Receivable, Progress Payment Offset Progress and performance-based payments received InternationalandOtherReceivableProgressPaymentsOffset Amount of progress payments offset against unbilled international and other contract receivables. Government Contract Receivable, Unbilled Amounts Government Contract Receivable, Unbilled Amounts Unbilled receivable, net of progress and performance-based payments received Unbilled Contract Receivable, net of progress and performance-based payments Unbilled Contract Receivable, net of progress and performance-based payments Allowance for doubtful accounts Allowance for Doubtful Unbilled Receivables Allowance for Doubtful Unbilled Receivables Unbilled receivables, net Unbilled Receivables, Current Fair Value of Financial Instruments Derivatives and Fair Value [Text Block] Principles of Consolidation Consolidation, Policy [Policy Text Block] Accounting Estimates Use of Estimates, Policy [Policy Text Block] Revenue Recognition Revenue [Policy Text Block] General and Administrative Expenses Selling, General and Administrative Expenses, Policy [Policy Text Block] Research and Development Research and Development Expense, Policy [Policy Text Block] Income Taxes Income Tax, Policy [Policy Text Block] Cash and cash equivalents Cash and Cash Equivalents, Policy [Policy Text Block] Fair Value of Financial Instruments Fair Value of Financial Instruments, Policy [Policy Text Block] Marketable Securities Marketable Securities, Policy [Policy Text Block] Derivative Financial Instruments Derivatives, Policy [Policy Text Block] Inventoried Costs Inventory Costs for Contracts or Programs, Policy [Policy Text Block] Cash Surrender Value of Life Insurance Policies Investment, Policy [Policy Text Block] Property, Plant and Equipment Property, Plant and Equipment, Policy [Policy Text Block] Goodwill and Other Purchased Intangible Assets Goodwill and Intangible Assets, Policy [Policy Text Block] Leases Lessee, Leases [Policy Text Block] Litigation, Commitments, and Contingencies Commitments and Contingencies, Policy [Policy Text Block] Environmental costs Environmental Costs, Policy [Policy Text Block] Retirement Benefits Pension and Other Postretirement Plans, Policy [Policy Text Block] Stock Compensation Share-based Payment Arrangement [Policy Text Block] Earnings Per Share Earnings Per Share, Policy [Policy Text Block] Fiscal Month Accounting Convention Basis of Accounting, Policy [Policy Text Block] Trade and Other Accounts Receivable, Unbilled Receivables, Policy [Policy Text Block] Trade and Other Accounts Receivable, Unbilled Receivables, Policy [Policy Text Block] New Accounting Pronouncements, Policy New Accounting Pronouncements, Policy [Policy Text Block] Summary of Significant Accounting Policies Organization, Consolidation and Presentation of Financial Statements Disclosure and Significant Accounting Policies [Text Block] Share-based Payment Arrangement [Abstract] Stock Award Rollforward Activity Share-based Compensation Arrangements by Share-based Payment Award, Performance-Based Units, Vested and Expected to Vest [Table Text Block] Cash Units and Cash Performance Units Aggregate Payout Amount [Table Text Block] Cash Units and Cash Performance Units Aggregate Payout Amount [Table Text Block] [Table Text Block] for Cash Units and Cash Performance Units Aggregate Payout Amount [Table] Statement of Financial Position [Abstract] Accumulated depreciation Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment Long-term Debt, Current Maturities Long-term Debt, Current Maturities Preferred Stock, par value Preferred Stock, Par or Stated Value Per Share Preferred Stock, shares authorized Preferred Stock, Shares Authorized Preferred Stock, shares issued Preferred Stock, Shares Issued Preferred Stock, shares outstanding Preferred Stock, Shares Outstanding Common stock, par value Common Stock, Par or Stated Value Per Share Common stock, shares authorized Common Stock, Shares Authorized Common stock, shares issued Common Stock, Shares, Issued Common stock, shares outstanding Common Stock, Shares, Outstanding Goodwill and Intangible Assets Goodwill and Intangible Assets Disclosure [Text Block] Schedule of Goodwill [Table] Schedule of Goodwill [Table] Segments [Axis] Segments [Axis] Segments Segments [Domain] Aerospace Systems [Member] Aerospace Systems [Member] Aerospace Systems reporting segment. Goodwill [Line Items] Goodwill [Line Items] Goodwill, Impaired, Accumulated Impairment Loss Goodwill, Impaired, Accumulated Impairment Loss Amortization of Intangible Assets Amortization of Intangible Assets Commitments and Contingencies Disclosure [Abstract] Commitments and Contingencies Commitments and Contingencies Disclosure [Text Block] Schedule of Segment Reporting Information, by Segment [Table] Schedule of Segment Reporting Information, by Segment [Table] Aerospace Systems Innovation Systems Innovation Systems [Member] Innovation Systems reporting segment Mission Systems Mission Systems [Member] Mission Systems reporting segment. Technology Services Technology Services [Member] Technology Services reporting segment. Corporate Corporate Segment [Member] Segment Reporting Information [Line Items] Segment Reporting Information [Line Items] Additional information by Segment (Table Amounts) [Abstract] Segment Reporting Information, Additional Information [Abstract] Capital Expenditures Payments to Acquire Property, Plant, and Equipment Depreciation and amortization Depreciation, Depletion and Amortization Statement of Stockholders' Equity [Abstract] Statement, Equity Components [Axis] Equity Components [Axis] Equity Component [Domain] Equity Component [Domain] Common stock Common Stock [Member] Paid-in capital Additional Paid-in Capital [Member] Retained earnings Retained Earnings [Member] Accumulated other comprehensive loss AOCI Attributable to Parent [Member] Beginning of year Stockholders' Equity Attributable to Parent Impact from adoption of ASU 2018-02 and ASU 2016-01 Impact from adoption of ASU 2018-02 and ASU 2016-01 Accounting Standards Update 2018-02 Income Statement - Reprting Comprehensive Income (Topic 220) and 2016-01 Financial Statements (Topic 825) Common stock repurchased Stock Repurchased and Retired During Period, Value Shares issued for employee stock awards and options Shares Issued, Value, Share-based Payment Arrangement, after Forfeiture Net earnings Dividends declared Dividends, Common Stock Other comprehensive loss, net of tax End of year Cash dividends declared per share Common Stock, Dividends, Per Share, Declared Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Plan Name [Axis] Plan Name [Axis] Plan Name [Domain] Plan Name [Domain] Amended 2011 Plan [Domain] Amended 2011 Plan [Domain] Amended 2011 Plan [Domain] 2011 Long-Term Incentive Stock Plan [Member] 2011 Long-Term Incentive Stock Plan [Member] 2011 Long-Term Incentive Stock Plan [Member] Award Type [Axis] Award Type [Axis] Award Type [Domain] Award Type [Domain] Share-based Compensation by Share-based Payment Award Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized Stock plans, vesting period Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period Stock awards, outstanding, weighted average remaining contractual terms Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Outstanding, Weighted Average Remaining Contractual Terms Stock issued, settlement of fully vested stock awards, fair value grant date Stock Issued During Period, Fair Value Grant Date, Share-based Compensation Stock Issued During Period, Fair Value Grant Date, Share-based Compensation Stock Award Activity (Table) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward] Stock awards - outstanding at period start Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number Stock awards - granted Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period Stock awards - vested Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period Stock awards - forfeited Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period Stock awards - outstanding at period end Stock Awards, Weighted Average Grant Date Fair Value [Table] Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract] Weighted-average grant date fair value - outstanding at period start Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value Weighted-average grant date fair value - granted Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value Weighted-average grant date fair value - vested Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value Weighted-average grant date fair value - forfeited Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value Weighted-average grant date fair value - outstanding at period end Consolidation Items [Axis] Consolidation Items [Axis] Consolidation Items [Domain] Consolidation Items [Domain] Operating Segments [Member] Operating Segments [Member] Corporate, Non-Segment [Member] Corporate, Non-Segment [Member] Total assets Assets Class of Treasury Stock [Table] Class of Treasury Stock [Table] Share Repurchase Program [Axis] Share Repurchase Program [Axis] Share Repurchase Program [Domain] Share Repurchase Program [Domain] September 2015 Share Repurchase Original Authorization [Member] September 2015 Share Repurchase Original Authorization [Member] September 2015 Share Repurchase Original Authorization [Member] Equity, Class of Treasury Stock [Line Items] Equity, Class of Treasury Stock [Line Items] Treasury Stock, Value, Acquired, Par Value Method Treasury Stock, Value, Acquired, Par Value Method Accelerated Share Repurchase Accelerated Share Repurchase Accelerated Share Repurchase Accelerated Share Repurchases, Payment Accelerated Share Repurchases, Payment Accelerated Share Repurchases, Payment Accelerated Share Repurchase Initial Receipt of Shares accelerated share repurchase initial receipt shares accelerated share repurchase initial receipt shares Accelerated Share Repurchase Initial Receipt Monetary Accelerated Share Repurchase Initial Receipt Monetary Accelerated Share Repurchase Initial Receipt Monetary Accelerated Share Repurchase Final Receipt Shares Accelerated Share Repurchase Final Receipt Shares Accelerated Share Repurchase Final Receipt Shares Accelerated Share Repurchases, Final Price Paid Per Share Accelerated Share Repurchases, Final Price Paid Per Share Earnings Per Share, Basic and Diluted [Abstract] Earnings Per Share, Basic and Diluted [Abstract] Dilutive effect of stock options and other stock awards granted Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements Stock Repurchase Program, Authorized Amount Stock Repurchase Program, Authorized Amount Increase (Decrease) in Stock Dividend, Percentage Increase (Decrease) in Stock Dividend, Percentage Increase (Decrease) in Stock Dividend, Percentage Common stock dividend (in dollars per share) Receivables [Abstract] Accounts receivable Schedule of Accounts, Notes, Loans and Financing Receivable [Table Text Block] Operating Segments Intersegment sales Intersegment Eliminations [Member] Segment Reconciling Items [Member] Segment Reconciling Items [Member] Sales and Service Revenues by Segment (Table Amounts) [Abstract] Segment Reporting Information, Revenue for Reportable Segment [Abstract] Number of reportable segments Number of Reportable Segments Sales Net FAS (service)/ CAS pension adjustment Net FAS (service)/ CAS pension adjustment Net FAS (service)/ CAS pension adjustment Pension plans with accumulated benefit obligations in excess of fair value of plan assets (Table Amounts) [Abstract] Defined Benefit Plan, Plan with Accumulated Benefit Obligation in Excess of Plan Assets [Abstract] Projected benefit obligation Defined Benefit Plan, Pension Plan with Accumulated Benefit Obligation in Excess of Plan Assets, Projected Benefit Obligation Accumulated benefit obligation Defined Benefit Plan, Plan with Accumulated Benefit Obligation in Excess of Plan Assets, Accumulated Benefit Obligation Fair value of plan assets Defined Benefit Plan, Plan with Accumulated Benefit Obligation in Excess of Plan Assets, Plan Assets Range Maximum Defined Benefit Plan, Plan Assets, Category [Axis] Defined Benefit Plan, Plan Assets, Category [Domain] International Equity Securities [Member] Hedge Funds [Member] Real Estate Funds OPB contributions Contribution Type [Axis] Contribution Type [Axis] Contribution Type [Axis] Contribution Type [Domain] Contribution Type [Domain] [Domain] for Contribution Type [Axis] Voluntary Contributions [Member] Voluntary Contributions [Member] Discretionary Contributions to the company's defined benefit plans Defined Benefit Plan, Plan Assets, Target Allocation, Percentage Defined Benefit Plan, Plan Assets, Target Allocation, Percentage Defined Benefit Plan, Expected Amortization of Prior Service Cost (Credit), Next Fiscal Year Defined Benefit Plan, Expected Amortization of Prior Service Cost (Credit), Next Fiscal Year Defined Contribution Plans Disclosure (Amounts in paragraphs) Defined Contribution Plan [Abstract] Defined Contribution Plan, Employer Discretionary Contribution Amount Defined Contribution Plan, Employer Discretionary Contribution Amount Expected 2019 employer contributions Defined Benefit Plan, Expected Future Employer Contributions, Next Fiscal Year Defined Benefit Plan, Plan Assets, Contributions by Employer Defined Benefit Plan, Plan Assets, Contributions by Employer Pension and post-retirement benefits disclosures (Amounts in paragraphs) Defined Benefit Plan [Abstract] Accumulated benefit obligation for all defined benefit pension plans Defined Benefit Plan, Accumulated Benefit Obligation Information About Plan Assets (Amounts in paragraphs) [Abstract] Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Unfunded Commitments Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Unfunded Commitments Average investment term, alternative investments Average Investment Term, Alternative Investments Average Investment Term, Alternative Investments Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Investment Redemption, Frequency Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Investment Redemption, Frequency Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Investment Redemption, Notice Period Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Investment Redemption, Notice Period Long-term debt Schedule of Long-term Debt Instruments [Table Text Block] Long-term debt maturities Schedule of Maturities of Long-term Debt [Table Text Block] Business Acquisition [Axis] Business Acquisition [Axis] Business Acquisition, Acquiree [Domain] Business Acquisition, Acquiree [Domain] Orbital ATK [Member] Orbital ATK [Member] Orbital ATK [Member] Goodwill (Table Amounts) Goodwill [Roll Forward] Beginning balance Goodwill Acquisition of Orbital ATK Goodwill, Acquired During Period Other Goodwill, Period Increase (Decrease) Ending balance Business Combinations [Abstract] Schedule of Business Acquisitions, by Acquisition [Table Text Block] Schedule of Business Acquisitions, by Acquisition [Table Text Block] Schedule of Recognized Identified Assets Acquired and Liabilities Assumed [Table Text Block] Schedule of Recognized Identified Assets Acquired and Liabilities Assumed [Table Text Block] Schedule of Finite-Lived Intangible Assets Acquired as Part of Business Combination [Table Text Block] Schedule of Finite-Lived Intangible Assets Acquired as Part of Business Combination [Table Text Block] Business Acquisition, Pro Forma Information [Table Text Block] Business Acquisition, Pro Forma Information [Table Text Block] Accounts Receivable, Net Loans, Notes, Trade and Other Receivables Disclosure [Text Block] Stock-based compensation expense Share-based Payment Arrangement, Expense Tax benefits from stock-based compensation expense Share-based Payment Arrangement, Expense, Tax Benefit Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount Weighted-average period for unrecognized compensation expense to be charged to expense Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition Schedule of Change in Accounting Estimate Schedule of Change in Accounting Estimate [Table Text Block] Contract with Customer, Asset and Liability Contract with Customer, Asset and Liability [Table Text Block] Property, Plant and Equipment Property, Plant and Equipment [Table Text Block] Accumulated Other Comprehensive Loss Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block] Document and Entity Information [Abstract] Document and Entity Information. Document Type Document Type Document Fiscal Period Focus Document Fiscal Period Focus Document Annual Report Document Annual Report Document Period End Date Document Period End Date Document Transition Report Document Transition Report Amendment Flag Amendment Flag Document Fiscal Year Focus Document Fiscal Year Focus Current Fiscal Year End Date Current Fiscal Year End Date Entity File Number Entity File Number Entity Registrant Name Entity Registrant Name Entity Central Index Key Entity Central Index Key Entity Incorporation, State or Country Code Entity Incorporation, State or Country Code Entity Tax Identification Number Entity Tax Identification Number Entity Address, Address Line One Entity Address, Address Line One Entity Address, City or Town Entity Address, City or Town Entity Address, State or Province Entity Address, State or Province Entity Address, Postal Zip Code Entity Address, Postal Zip Code City Area Code City Area Code Local Phone Number Local Phone Number Title of 12(b) Security Title of 12(b) Security Trading Symbol Trading Symbol Security Exchange Name Security Exchange Name Entity Well-known Seasoned Issuer Entity Well-known Seasoned Issuer Entity Voluntary Filers Entity Voluntary Filers Entity Current Reporting Status Entity Current Reporting Status Entity Interactive Data Current Entity Interactive Data Current Entity Filer Category Entity Filer Category Entity Small Business Entity Small Business Entity Emerging Growth Company Entity Emerging Growth Company Entity Shell Company Entity Shell Company Entity Public Float Entity Public Float Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Documents Incorporated by Reference Documents Incorporated by Reference [Text Block] Schedule of Goodwill [Table Text Block] Schedule of Goodwill [Table Text Block] Schedule of Acquired Finite-Lived Intangible Assets by Major Class [Table Text Block] Schedule of Acquired Finite-Lived Intangible Assets by Major Class [Table Text Block] Schedule of Finite-Lived Intangible Assets, Future Amortization Expense [Table Text Block] Schedule of Finite-Lived Intangible Assets, Future Amortization Expense [Table Text Block] Segment Information Segment Reporting Disclosure [Text Block] Summary of Significant Accounting Policies (Amounts in paragraphs) Accounting Policies [Abstract] Research and development expenses Research and Development Expense Research and Development as a Percent of Sales Research and Development as a Percent of Sales Research and Development as a Percent of Sales Cash surrender value of life insurance Cash Surrender Value of Life Insurance Schedule of Change in Accounting Estimate [Table] Schedule of Change in Accounting Estimate [Table] Segments Change in Accounting Estimate by Type [Axis] Change in Accounting Estimate by Type [Axis] Change in Accounting Estimate, Type [Domain] Change in Accounting Estimate, Type [Domain] Contracts Accounted for under Percentage of Completion [Member] Contracts Accounted for under Percentage of Completion [Member] Change in Accounting Estimate [Line Items] Change in Accounting Estimate [Line Items] Contract with Customer, Performance Obligation Satisfied in Previous Period Contract with Customer, Performance Obligation Satisfied in Previous Period Changes in Unamortized Benefit plan Costs (Table Amounts) [Abstract] Defined Benefit Plan, Amounts Recognized in Other Comprehensive Income (Loss) [Abstract] Amortization of: Amortization Of Prior Service Cost And Losses [Abstract] Amortization of Prior Service Cost and Losses. Prior service credit Other Comprehensive (Income) Loss, Defined Benefit Plan, Prior Service Cost (Credit), Reclassification Adjustment from AOCI, before Tax Tax expense (benefit) related to above items Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, Tax Change in unamortized benefit plan costs Property, Plant and Equipment [Table] Property, Plant and Equipment [Table] Adjustments for New Accounting Pronouncements [Axis] Adjustments for New Accounting Pronouncements [Axis] Type of Adoption [Domain] Type of Adoption [Domain] Range Property, Plant and Equipment, Type [Axis] Property, Plant and Equipment, Type [Axis] Property, Plant and Equipment, Type [Domain] Property, Plant and Equipment, Type [Domain] Land and land improvements Land and Land Improvements [Member] Buildings and improvements Building and Building Improvements [Member] Machinery and other equipment Machinery and Equipment [Member] Capitalized software costs Software and Software Development Costs [Member] Leasehold improvements Leasehold Improvements [Member] Property, Plant and Equipment Property, Plant and Equipment [Line Items] Property, plant and equipment, at cost Property, Plant and Equipment, Gross Accumulated depreciation Property, plant, and equipment, net Property, Plant and Equipment, Net Property, plant and equipment, estimated useful life Property, Plant and Equipment, Useful Life Environmental Remediation [Table Text Block] Environmental Remediation [Table Text Block] Environmental Remediation Range of Possible Future Costs, Accrued Costs within that range and Deferred Cost expected to be recovered [Table Text Block] Assets and Liabilities, Lessee [Abstract] Operating lease right-of-use assets Operating Lease, Right-of-Use Asset Operating Lease, Liability, Current Operating Lease, Liability, Current Operating Lease, Liability, Noncurrent Operating Lease, Liability, Noncurrent Total operating lease liabilities Earnings Per Share, Share Repurchases and Dividends on Common Stock Stockholders' Equity Note Disclosure [Text Block] Income Tax Reconciliation (Table Amounts) [Abstract] Effective Income Tax Rate Reconciliation, Amount [Abstract] Income tax expense at statutory rate Effective Income Tax Rate Reconciliation at Federal Statutory Income Tax Rate, Amount Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent Stock compensation - excess tax benefits Effective Income Tax Rate Reconciliation, Deduction, Other, Amount Stock compensation - excess tax benefits, Percent Effective Income Tax Rate Reconciliation, Deduction, Other, Percent Research credit Effective Income Tax Rate Reconciliation, Tax Credit, Research, Amount Research credit, Percent Effective Income Tax Rate Reconciliation, Tax Credit, Research, Percent Foreign derived intangible income IncomeTaxReconciliationDeductionsFDII Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to foreign derived intangible income deductions. Foreign derived intangible income, Percent IncomeTaxReconciliationDeductionsFDII, Percent IncomeTaxReconciliationDeductionsFDII, Percent Manufacturing deduction Manufacturing deduction, Percent Effective Income Tax Rate Reconciliation, Deduction, Qualified Production Activity, Percent Settlements with taxing authorities Effective Income Tax Rate Reconciliation, Tax Settlement, Amount Settlements with taxing authorities, Percent Effective Income Tax Rate Reconciliation, Tax Settlement, Percent Effective Income Tax Rate Reconciliation, Tax Cuts and Jobs Act, Percent Effective Income Tax Rate Reconciliation, Tax Cuts and Jobs Act, Percent Effective Tax Rate Reconciliation, Mark-to-Market benefit tax rate differential, amount Effective Tax Rate Reconciliation, Mark-to-Market benefit tax rate differential, percent Effective Tax Rate Reconciliation, Mark-to-Market benefit tax rate differential, percent Effective Tax Rate Reconciliation, Mark-to-Market benefit tax rate differential, percent Other, net Effective Income Tax Rate Reconciliation, Other Adjustments, Amount Other net, Percent Effective Income Tax Rate Reconciliation, Other Adjustments, Percent Total federal and foreign income tax expense Components of net periodic benefit cost Schedule of Costs of Retirement Plans [Table Text Block] Changes in unamortized benefit plan costs Schedule of Amounts Recognized in Other Comprehensive Income (Loss) [Table Text Block] Change in plan assets and amounts recognized in the consolidated statements of financial position Changes in Projected Benefit Obligations, Fair Value of Plan Assets, and Funded Status of Plan [Table Text Block] Pension plans with accumulated benefit obligations in excess of fair value of plan assets Defined Benefit Plan, Plan with Accumulated Benefit Obligation in Excess of Plan Assets [Table Text Block] Weighted-average plan assumptions Defined Benefit Plan, Assumptions [Table Text Block] Plan asset allocation Schedule of Allocation of Plan Assets [Table Text Block] Estimated benefit payments Schedule of Expected Benefit Payments [Table Text Block] Schedule of Long-term Debt Instruments [Table] Schedule of Long-term Debt Instruments [Table] Long-term Debt, Type [Axis] Long-term Debt, Type [Axis] Long-term Debt, Type [Domain] Long-term Debt, Type [Domain] Debt Instrument [Axis] Debt Instrument [Axis] Debt Instrument, Name [Domain] Debt Instrument, Name [Domain] 2019 Two Thousand Nineteen [Member] 2019. 2020 Two Thousand Twenty [Member] 2020 2021 Two Thousand Twenty One [Member] 2021. 2022 Two Thousand Twenty Two [Member] 2022 2023 Two Thousand Twenty Three [Member] Two Thousand Twenty Three [Member] 2025 Two Thousand Twenty Five [Member] 2025 2026 Two Thousand Twenty Six [Member] 2026. 2027 Two Thousand Twenty Seven [Member] 2027 2028 Two Thousand Twenty Eight [Member] 2028 2031 Two Thousand Thirty One [Member] 2031. 2040 Two Thousand Forty [Member] 2040. 2043 Two Thousand Forty Three [Member] Two Thousand Forty Three [Member] 2045 Two Thousand Forty Five [Member] Two Thousand Forty Five [Member] 2047 Two Thousand Forty Seven [Member] 2047 Two Year Term [Member] [Domain] Two Year Term [Member] [Domain] Two Year Term [Member] [Domain] Debt Instrument [Line Items] Debt Instrument [Line Items] Long-Term Debt (Table Amounts) [Abstract] Debt Instruments [Abstract] Debt Instrument, Interest Rate, Stated Percentage Debt Instrument, Interest Rate, Stated Percentage Long-term debt Credit facilities Long-term Line of Credit Other long-term debt Other Long-term Debt Total long-term debt Debt and Lease Obligation Less: current portion Long-term Debt and Lease Obligation Schedule of Business Acquisitions, by Acquisition [Table] Schedule of Business Acquisitions, by Acquisition [Table] Finite-Lived Intangible Assets by Major Class [Axis] Finite-Lived Intangible Assets by Major Class [Axis] Finite-Lived Intangible Assets, Major Class Name [Domain] Finite-Lived Intangible Assets, Major Class Name [Domain] Customer Relationships [Member] Customer Relationships [Member] Customer Contracts [Member] Customer Contracts [Member] Business Acquisition [Line Items] Business Acquisition [Line Items] Acquired Finite-lived Intangible Assets, Weighted Average Useful Life Acquired Finite-lived Intangible Assets, Weighted Average Useful Life Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill Goodwill Quarterly Financial Information [Text Block] Quarterly Financial Information [Text Block] Schedule of Acquired Finite-Lived Intangible Asset by Major Class [Table] Schedule of Acquired Finite-Lived Intangible Asset by Major Class [Table] Acquired Finite-Lived Intangible Assets [Line Items] Acquired Finite-Lived Intangible Assets [Line Items] Gross customer-related and other intangible assets Finite-Lived Intangible Assets, Gross Less accumulated amortization Finite-Lived Intangible Assets, Accumulated Amortization Net contract, program and other intangible assets Finite-Lived Intangible Assets, Net Intersegment sales and operating income (Table Amounts) [Abstract] Segment Reporting Information, Operating Income (Loss) [Abstract] Schedule of Revenues from External Customers and Long-Lived Assets [Table] Schedule of Revenues from External Customers and Long-Lived Assets [Table] Mission Systems [Member] Technology Services [Member] Geographical [Axis] Geographical [Axis] Geographical [Domain] Geographical [Domain] United States UNITED STATES Asia/Pacific Asia Pacific [Member] All Other All Other - Geographic Region [Domain] All Other - Geographic Region [Domain] Intersegment Sales [Member] Intersegment Sales [Member] Revenues from External Customers and Long-Lived Assets [Line Items] Revenues from External Customers and Long-Lived Assets [Line Items] Concentration Risk, Percentage Concentration Risk, Percentage Fair value of assets and liabilities measured on a recurring basis Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block] Loss Contingencies [Table] Loss Contingencies [Table] Balance Sheet Location [Axis] Balance Sheet Location [Axis] Balance Sheet Location [Domain] Balance Sheet Location [Domain] Other Current Liabilities [Member] Other Current Liabilities [Member] Other Noncurrent Liabilities [Member] Other Noncurrent Liabilities [Member] Prepaid Expenses and Other Current Assets [Member] Prepaid Expenses and Other Current Assets [Member] Other Noncurrent Assets [Member] Other Noncurrent Assets [Member] Loss Contingencies [Line Items] Loss Contingencies [Line Items] Environmental Commitments and Contingencies (Amounts in Paragraphs) Loss Contingency [Abstract] Amounts accrued for probable environmental remediation costs Accrual for Environmental Loss Contingencies Loss Contingency, Range of Possible Loss, Portion Not Accrued Loss Contingency, Range of Possible Loss, Portion Not Accrued Recorded Third-Party Environmental Recoveries, Amount Recorded Third-Party Environmental Recoveries, Amount Financial Arrangements (Amounts in Paragraph) Other Commitments [Abstract] Unused standby letters of credit and bank guarantees Standby Unused Letters Of Credit and bank guarantees Financial instruments issued by a bank, on behalf of the company and in favor of a beneficiary, which substitutes the company's credit worthiness with that of the bank. Letters of Credit are usually issued in conformance with a set of governing rules. Surety Bond Outstanding Surety Bond Outstanding Surety Bond Outstanding Inventoried Costs, Net Inventory Disclosure [Text Block] Tax expense on the change in unamortized prior service credits Retirement Benefits Pension and Other Postretirement Benefits Disclosure [Text Block] Future Minimum Lease Payments Under 840 [Abstract] Future Minimum Lease Payments Under 840 [Abstract] Operating Leases, Rent Expense Operating Leases, Rent Expense Operating Leases, Future Minimum Payments Due, Next Twelve Months Operating Leases, Future Minimum Payments Due, Next Twelve Months Operating Leases, Future Minimum Payments, Due in Two Years Operating Leases, Future Minimum Payments, Due in Two Years Operating Leases, Future Minimum Payments, Due in Three Years Operating Leases, Future Minimum Payments, Due in Three Years Operating Leases, Future Minimum Payments, Due in Four Years Operating Leases, Future Minimum Payments, Due in Four Years Operating Leases, Future Minimum Payments, Due in Five Years Operating Leases, Future Minimum Payments, Due in Five Years Operating Leases, Future Minimum Payments, Due Thereafter Operating Leases, Future Minimum Payments, Due Thereafter Operating Leases, Future Minimum Payments Due Operating Leases, Future Minimum Payments Due Loans, Notes, Trade and Other Receivables Disclosure [Text Block] Unbilled Receivables Disclosure [Text Block] Unbilled Receivables Disclosure [Text Block] Inventoried Costs Schedule of Inventory, Current [Table Text Block] Fair Value, by Balance Sheet Grouping [Table] Fair Value, Recurring and Nonrecurring [Table] Measurement Frequency [Axis] Measurement Frequency [Axis] Measurement Frequency [Domain] Measurement Frequency [Domain] Fair Value, Recurring [Member] Fair Value, Recurring [Member] Fair Value, Nonrecurring [Member] Fair Value, Nonrecurring [Member] Fair Value Hierarchy and NAV [Axis] Fair Value, Inputs, Level 1 [Member] Fair Value, Inputs, Level 2 [Member] 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] Marketable Securities Marketable Securities Derivative Assets (Liabilities), at Fair Value, Net Derivative Assets (Liabilities), at Fair Value, Net Stock Compensation Plans and Other Compensation Arrangements Share-based Payment Arrangement [Text Block] Cash and Cash Equivalents [Member] Equity Securities [Member] Equity Securities [Member] Alternative investments Real Estate And Other Securities [Member] Investments in registered hedge funds, private equities, properties and other holdings. Plan Asset Allocation Ranges (Table Amounts) [Abstract] Defined Benefit Plan, Plan Assets, Allocations [Abstract] Income tax expense Schedule of Components of Income Tax Expense (Benefit) [Table Text Block] Income tax reconciliation Schedule of Effective Income Tax Rate Reconciliation [Table Text Block] Unrecognized tax benefit rollforward Schedule of Unrecognized Tax Benefits Roll Forward [Table Text Block] Components of deferred tax assets and liabilities Schedule of Deferred Tax Assets and Liabilities [Table Text Block] Revenue, Remaining Performance Obligation, Amount Revenue, Remaining Performance Obligation, Amount Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Explanation Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Explanation Unbilled Receivables, Current Amount of increase (decrease) in Unbilled Receivables Increase (Decrease) in Contract with Customer, Asset Percent increase (decrease) in Unbilled Receivables Percent increase (decrease) in Contract Asset Percent increase (decrease) in Contract Asset Contract with Customer, Liability, Current Contract with Customer, Liability, Current Amount of decrease (increase) in Contract with Customer, Liability, Current Increase (Decrease) in Contract with Customer, Liability Percent decrease (increase) in Contract with Customer, Liability, Current Percent decrease (increase) in Contract with Customer, Liability, Current Percent decrease (increase) in Contract with Customer, Liability, Current Contract with Customer, Asset, Net, Current Contract with Customer, Asset, Net, Current Amount of increase (decrease) in net contract assets (liabilities) Amount of increase (decrease) in net contract assets (liabilities) Amount of increase (decrease) in net contract assets (liabilities) Percent increase (decrease) in net contract assets (liabilities) Percent increase (decrease) in net contract assets (liabilities) Percent increase (decrease) in net contract assets (liabilities) Contract with Customer, Liability, Revenue Recognized Contract with Customer, Liability, Revenue Recognized Components of Net Periodic Benefit Cost (Table Amounts) [Abstract] Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract] Service cost Defined Benefit Plan, Service Cost Interest cost Defined Benefit Plan, Interest Cost Expected return on plan assets Defined Benefit Plan, Expected Return (Loss) on Plan Assets Amortization of prior service credit Defined Benefit Plan, Amortization of Prior Service Cost (Credit) Mark-to-market expense (benefit) Other Defined Benefit Plan, Other Cost (Credit) Net periodic benefit cost (benefit) Defined Benefit Plan, Net Periodic Benefit Cost (Credit) Operating lease cost Operating Lease, Cost Variable lease cost Variable Lease, Cost Short-term lease cost Short-term Lease, Cost Total lease cost Lease, Cost Schedule of Share Repurchases, by Program [Table] September 2015 Share Repurchase Original Authorization December 2018 Share Repurchase Program Original Authorization December 2018 Share Repurchase Original Authorization [Member] December 2018 Share Repurchase Original Authorization [Member] Stock Repurchase [Line Items] Amount Authorized Total Shares Retired Treasury Stock, Shares, Retired Average Price Per Share Treasury Stock Acquired, Average Cost Per Share Shares Repurchased Stock Repurchased and Retired During Period, Shares Amount repurchased Amount remaining under authorization for share repurchases Stock Repurchase Program, Remaining Authorized Repurchase Amount Claim Amount [Axis] Claim Amount [Axis] Claim Amount [Axis] - Defines movements in claim amounts from litigation matters. Claim Amount [Domain] Claim Amount [Domain] [Domain] for Claim Amount [Axis] - Defines movements in claim amounts from litigation matters. Initial Claim [Member] Initial Claim [Member] Initial Claim [Member] - Amount of initial claim in a litigation matter. Incremental claim [Member] Incremental claim [Member] Incremental claim [Member] - Incremental claim related to a litigation matter. Loss Contingency Nature [Axis] Loss Contingency Nature [Axis] Loss Contingency, Nature [Domain] Loss Contingency, Nature [Domain] United States Postal Service [Member] United States Postal Service [Member] United States Postal Service [Member] Solystic Matter [Member] Solystic Matter [Member] Solystic Matter [Member] Gain Contingencies, Nature [Axis] Gain Contingencies, Nature [Axis] Gain Contingency, Nature [Domain] Gain Contingency, Nature [Domain] Unpaid Portions of Contract Price and Direct Costs Incurred [Member] Unpaid Portions of Contract Price and Direct Costs Incurred [Member] Unpaid Portions of Contract Price and Direct Costs Incurred [Member] Acts and Omissions with Adverse Affects on Performance and Obligations [Member] Acts and Omissions with Adverse Affects on Performance and Obligations [Member] Acts and Omissions with Adverse Affects on Performance and Obligations [Member] Litigation Case [Axis] Litigation Case [Axis] Litigation Case Type [Domain] Litigation Case [Domain] False Claims Act [Member] False Claims Act [Member] False Claims Act [Member] Orbital ATK [Domain] Litigation Status [Axis] Litigation Status [Axis] Litigation Status [Domain] Litigation Status [Domain] Threatened Litigation [Member] Threatened Litigation [Member] Contract award Contract Award Total Contract Award Receivables, unpaid long-term contracts Receivables, Long-term Contracts or Programs Gain Contingency, Unrecorded Amount Gain Contingency, Unrecorded Amount Loss Contingency, Estimate of Possible Loss Loss Contingency, Estimate of Possible Loss Loss Contingency, Number of Defendants Loss Contingency, Number of Defendants Loss Contingency, Damages Sought, Value Loss Contingency, Damages Sought, Value CounterclaimForDamagesSought CounterclaimForDamagesSought CounterclaimForDamagesSought Counterclaim Counterclaim Counterclaim for damages sought Loss Contingency, Damages Awarded, Value Loss Contingency, Damages Awarded, Value Assets Assets [Abstract] Cash and cash equivalents Cash and Cash Equivalents, at Carrying Value Accounts receivable, net Accounts Receivable, after Allowance for Credit Loss, Current Unbilled receivables, net Inventoried costs, net Prepaid expenses and other current assets Other Assets, Current Total current assets Assets, Current Property, plant and equipment, net of accumulated depreciation of $5,850 for 2019 and $5,369 for 2018 Operating lease right-of-use assets Goodwill Intangible assets, net Intangible Assets, Net (Excluding Goodwill) Deferred tax assets Deferred Tax Assets, Net, Noncurrent Other non-current assets Other Assets, Noncurrent Total assets Liabilities Liabilities [Abstract] Trade accounts payable Accounts Payable, Current Accrued employee compensation Employee-related Liabilities, Current Advance payments and billings in excess of costs incurred Other current liabilities Other Liabilities, Current Total current liabilities Liabilities, Current Long-term debt, net of current portion of $1,109 for 2019 and $517 for 2018 Pension and other postretirement benefit plan liabilities Liability, Defined Benefit Plan, Noncurrent Operating lease liabilities Deferred tax liabilities Deferred Tax Liabilities, Net, Noncurrent Other non-current liabilities Other Liabilities, Noncurrent Total liabilities Liabilities Commitments and contingencies (Note 12) Commitments and Contingencies Shareholders’ equity Stockholders' Equity Attributable to Parent [Abstract] Preferred stock, $1 par value; 10,000,000 shares authorized; no shares issued and outstanding Preferred Stock, Value, Issued Common stock, $1 par value; 800,000,000 shares authorized; issued and outstanding: 2019—167,848,424 and 2018—170,607,336 Common Stock, Value, Issued Paid-in capital Additional Paid in Capital, Common Stock Retained earnings Retained Earnings (Accumulated Deficit) Accumulated other comprehensive loss Total shareholders’ equity Total liabilities and shareholders’ equity Liabilities and Equity Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Intangibles Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Intangibles Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Other current liabilities Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Other current liabilities This element represents the amount of any measurement period adjustment (as defined) realized during the reporting period to Other current liabilities acquired in connection with a business combination for which the initial accounting was incomplete. Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Pension and other post-retirement benefit plan liabilities Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Pension and other post-retirement benefit plan liabilities This element represents the amount of any measurement period adjustment (as defined) realized during the reporting period to Pension and other post-retirement benefit plan liabilities acquired in connection with a business combination for which the initial accounting was incomplete. Business Combination, Provisional, Initial Accounting Incomplete, Adjustments, Other Non-Current Liabilities Business Combination, Provisional, Initial Accounting Incomplete, Adjustments, Other Non-Current Liabilities Business Combination, Provisional, Initial Accounting Incomplete, Adjustments, Other Non-Current Liabilities Business Combination, Provisional, Initial Accounting Incomplete, Adjustments, Other Current Assets Business Combination, Provisional, Initial Accounting Incomplete, Adjustments, Other Current Assets Business Combination, Provisional, Initial Accounting Incomplete, Adjustments, Other Current Assets Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Goodwill Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Goodwill This element represents the amount of any measurement period adjustment (as defined) realized during the reporting period to intangibles acquired in connection with a business combination for which the initial accounting was incomplete. Cash and cash equivalents Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Cash and Equivalents Accounts receivable Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Receivables Unbilled receivables Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Unbilled Receivables Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Unbilled Receivables Inventoried costs Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Inventory Other current assets Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Prepaid Expense and Other Assets Property, plant and equipment Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment Intangible assets Other non-current assets Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Other Noncurrent Assets Total assets acquired Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets Trade accounts payable Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Accounts Payable Accrued employee compensation Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Employee-related liabilities Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Employee-related liabilities Advance payments and billings in excess of costs incurred Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Customer Advances Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Customer Advances Below market contracts(1) Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Below Market Contracts Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Below Market Contracts Other current liabilities Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Other Long-term debt Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities, Long-term Debt Pension and OPB plan liabilities Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, NonCurrent Liabilities, Defined Benefit Plan Liability Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, NonCurrent Liabilities, Defined Benefit Plan Liability Deferred tax liabilities Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Liabilities Other non-current liabilities Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities, Other Total liabilities assumed Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities Total purchase price Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net Shares of Orbital ATK common stock outstanding as of the Merger date Shares, Outstanding Cash consideration per share of Orbital ATK common stock Business Acquisition, Share Price Total purchase price Business Combination, Consideration Transferred Unaudited Selected Quarterly Data (Table Amounts) [Abstract] Quarterly Financial Data [Abstract] Weighted-average common shares outstanding Weighted-average diluted shares outstanding Business Combination Disclosure [Text Block] Business Combination Disclosure [Text Block] Lease Other Supplemental Information (Details 3) [Abstract] Lease Other Supplemental Information (Details 3) [Abstract] Cash paid for amounts included in the measurement of operating lease liabilities Operating Lease, Payments Right-of-use assets obtained in exchange for new lease liabilities Right-of-Use Asset Obtained in Exchange for Operating Lease Liability Operating Lease, Weighted Average Remaining Lease Term Operating Lease, Weighted Average Remaining Lease Term Operating Lease, Weighted Average Discount Rate, Percent Operating Lease, Weighted Average Discount Rate, Percent Investigations, Claims and Litigation Legal Matters and Contingencies [Text Block] Schedule of Revenue by Major Customers, by Reporting Segments [Table] Schedule of Revenue by Major Customers, by Reporting Segments [Table] Customer [Axis] Customer [Axis] Customer [Domain] Customer [Domain] US Government International International Customer [Member] International Customer Other Customers Other Customers [Member] US state and local government and US commercial customers. Intersegment Sales [Member] Revenue, Major Customer [Line Items] Revenue, Major Customer [Line Items] Short-term Debt, Type [Axis] Short-term Debt, Type [Axis] Short-term Debt, Type [Domain] Short-term Debt, Type [Domain] Commercial Paper [Member] Commercial Paper [Member] Variable Rate [Axis] Variable Rate [Axis] Variable Rate [Domain] Variable Rate [Domain] London Interbank Offered Rate (LIBOR) [Member] London Interbank Offered Rate (LIBOR) [Member] Credit Facility [Axis] Credit Facility [Axis] Credit Facility [Domain] Credit Facility [Domain] Revolving Credit Facility [Member] Revolving Credit Facility [Member] Five Year Term [Member] [Domain] Five Year Term [Member] [Domain] Five Year Term [Member] Commercial Paper, Maximum Borrowing Capacity Commercial Paper, Maximum Borrowing Capacity Commercial Paper, Maximum Borrowing Capacity Short-term Debt Short-term Debt Short-term Debt, Weighted Average Interest Rate, at Point in Time Short-term Debt, Weighted Average Interest Rate, at Point in Time Debt Instrument, Term Debt Instrument, Term Line of Credit Facility, Maximum Borrowing Capacity Line of Credit Facility, Maximum Borrowing Capacity Line of Credit Facility, Interest Rate During Period Line of Credit Facility, Interest Rate During Period Credit Facility, Covenant Terms, Maximum Debt to Capitalization Ratio Line of Credit Facility, Covenant Terms Line of Credit Facility, Covenant Compliance Line of Credit Facility, Covenant Compliance Long-term Debt, Fair Value Long-term Debt, Fair Value Interest paid, net of interest received Interest paid, net of interest received The amount of cash paid for interest on money borrowed, including capitalized interest , net of interest received on loans and other debt instruments during the current period. Reconciliation of Revenue from Segments to Consolidated [Table] Reconciliation of Revenue from Segments to Consolidated [Table] Contract with Customer, Basis of Pricing [Axis] Contract with Customer, Basis of Pricing [Axis] Contract with Customer, Basis of Pricing [Domain] Contract with Customer, Basis of Pricing [Domain] Cost-type Time-and-materials Contract [Member] Fixed-price Fixed-price Contract [Member] Intersegment Sales [Member] Revenue, Contract Type [Line Items] Segment Reporting, Revenue Reconciling Item [Line Items] Cash Units and Cash Performance Units [Member] Cash Units and Cash Performance Units [Member] Cash Units and Cash Performance Units [Member] Grants During 2010 and After [Member] Grants During 2010 and After [Member] Grants During 2010 and After [Member] Share Based Compensation Arrangement By Share Based Payment Award Award Grants Percentage Financial Metric Met Exceeded Share Based Compensation Arrangement By Share Based Payment Award Award Grants Percentage Financial Metric Met Exceeded Share based compensation arrangement by share based payment award award grants percentage financial metric met exceeded. Deferred Compensation Cash-based Arrangements, Liability, Current Deferred Compensation Cash-based Arrangements, Liability, Current Income Taxes Income Tax Disclosure [Text Block] Business Combination, Consideration Transferred Operating Income (Loss) Business Combination, Acquisition Related Costs Business Combination, Acquisition Related Costs Business Acquisition, Pro Forma Revenue Business Acquisition, Pro Forma Revenue Business Acquisition, Pro Forma Net Income (Loss) Business Acquisition, Pro Forma Net Income (Loss) Business Acquisition, Pro Forma Earnings Per Share, Diluted Business Acquisition, Pro Forma Earnings Per Share, Diluted Pro Forma Adjustments, Orbital ATK ASC606 Sales adjustment Pro Forma Adjustments, Orbital ATK ASC606 Sales adjustment Pro Forma Adjustments, Orbital ATK ASC606 Sales adjustment Pro Forma Adjustments, Orbital ATK ASC606 Cost of Sales adjustment Pro Forma Adjustments, Orbital ATK ASC606 Cost of Sales adjustment Pro Forma Adjustments, Orbital ATK ASC606 Cost of Sales adjustment Pro Forma Adjustments, Orbital ATK intercompany sales elimination Pro Forma Adjustments, Orbital ATK intercompany sales elimination Pro Forma Adjustments, Orbital ATK intercompany sales elimination Pro Forma Adjustments, Elimination of nonrecurring transaction costs Pro Forma Adjustments, Elimination of nonrecurring transaction costs Business combination, transaction costs Pro Forma Adjustments, Additional depreciation expense, net of removal of historical depreciation Pro Forma Adjustments, Additional depreciation expense, net of removal of historical depreciation Pro Forma Adjustments, Additional depreciation expense, net of removal of historical depreciation Pro Forma Adjustments, Additional interest expense due to debt issued to finance merger Pro Forma Adjustments, Additional interest expense due to debt issued to finance merger Pro Forma Adjustments, Additional interest expense due to debt issued to finance merger Pro Forma Adjustments, Additional amortization expense, net of removal of historical amortization expense Pro Forma Adjustments, Additional amortization expense, net of removal of historical amortization expense Pro Forma Adjustments, Additional amortization expense, net of removal of historical amortization expense Pro Forma Adjustments, Elimination of Orbital ATK’s historical amortization of net actuarial losses and prior service credits and revised pension and other post-retirement costs Pro Forma Adjustments, Elimination of Orbital ATK’s historical amortization of net actuarial losses and prior service credits and revised pension and other post-retirement costs Pro Forma Adjustments, Elimination of Orbital ATK’s historical amortization of net actuarial losses and prior service credits and revised pension and other post-retirement costs Income Tax Effects of Pro Forma Adjustments Income Tax Effects of Pro Forma Adjustments Income Tax Effects of Pro Forma Adjustments Change in plan assets Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward] Fair value of plan assets at beginning of year Net gain (loss) on plan assets Defined Benefit Plan, Plan Assets, Increase (Decrease) for Actual Return (Loss) Employer contributions Participant contributions Defined Benefit Plan, Plan Assets, Contributions by Plan Participant Benefits paid Defined Benefit Plan, Plan Assets, Benefits Paid Acquired plan assets Defined Benefit Plan, Plan Assets, Business Combination Other Defined Benefit Plan Other Change In Plan Assets Component of change in plan assets that is not otherwise reflected in the taxonomy. Fair value of plan assets at end of year Change in projected benefit obligation Defined Benefit Plan, Change in Benefit Obligation [Roll Forward] Projected benefit obligation at beginning of year Defined Benefit Plan, Benefit Obligation Participant contributions Defined Benefit Plan, Benefit Obligation, Contributions by Plan Participant Actuarial loss (gain) Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss) Benefits paid Defined Benefit Plan, Benefit Obligation, Benefits Paid Acquired benefit obligation Defined Benefit Plan, Benefit Obligation, Business Combination Other Defined Benefit Plan, Benefit Obligation, Increase (Decrease) for Other Change Projected benefit obligation at end of year Funded status Defined Benefit Plan, Funded (Unfunded) Status of Plan Amounts Recognized on the Balance Sheet Defined Benefit Plan, Amounts for Asset (Liability) Recognized in Statement of Financial Position [Abstract] Non-current assets Assets for Plan Benefits, Defined Benefit Plan Current liability Liability, Defined Benefit Plan, Current Non-current liability Statement of Cash Flows [Abstract] Operating activities Net Cash Provided by (Used in) Operating Activities [Abstract] Adjustments to reconcile to net cash provided by operating activities: Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] Mark-to-market pension and OPB expense (benefit) Pension and Other Postretirement Benefits Expense (Reversal of Expense), Noncash Non-cash lease expense NoncashLeaseExpense NoncashLeaseExpense Stock-based compensation Share-based Payment Arrangement, Noncash Expense Deferred income taxes Deferred Income Taxes and Tax Credits Changes in assets and liabilities: Increase (Decrease) in Operating Assets [Abstract] Accounts receivable, net Increase (Decrease) in Accounts Receivable Unbilled receivables, net Increase (Decrease) in Unbilled Receivables Inventoried costs, net Increase (Decrease) in Inventories Prepaid expenses and other assets Increase (Decrease) in Prepaid Expense and Other Assets Accounts payable and other liabilities Increase (Decrease) in Accounts Payable and Accrued Liabilities Income taxes payable, net Increase (Decrease) in Income Taxes Payable Retiree benefits Increase (Decrease) in Obligation, Pension and Other Postretirement Benefits Other, net Other Noncash Income (Expense) Net cash provided by operating activities Net Cash Provided by (Used in) Operating Activities Investing activities Net Cash Provided by (Used in) Investing Activities [Abstract] Acquisition of Orbital ATK, net of cash acquired Payments to Acquire Businesses, Net of Cash Acquired Capital expenditures Other investing activities, net Payments for (Proceeds from) Other Investing Activities Net cash used in investing activities Net Cash Provided by (Used in) Investing Activities Financing activities Net Cash Provided by (Used in) Financing Activities [Abstract] Payments of long-term debt Repayments of Long-term Debt Net proceeds from issuance of long-term debt Proceeds from Issuance of Long-term Debt Payments to credit facilities Proceeds from (Repayments of) Lines of Credit Net (repayments of) borrowings on commercial paper Proceeds from (Repayments of) Commercial Paper Common stock repurchases Payments for Repurchase of Common Stock Cash dividends paid Payments of Ordinary Dividends, Common Stock Payments of employee taxes withheld from share-based awards Payment, Tax Withholding, Share-based Payment Arrangement Other financing activities, net Proceeds from (Payments for) Other Financing Activities Net cash (used in) provided by financing activities Net Cash Provided by (Used in) Financing Activities Increase (decrease) in cash and cash equivalents Cash and Cash Equivalents, Period Increase (Decrease) Cash and cash equivalents, beginning of year Cash and cash equivalents, end of year Long-Term Debt Debt Disclosure [Text Block] Income Tax Expense (Table Amounts) [Abstract] Components of Income Tax Expense (Benefit), Continuing Operations [Abstract] Income Taxes on Continuing Operations (Table Amounts) Income Tax Expense (Benefit), Continuing Operations [Abstract] Current federal income tax expense (benefit) Current Federal Tax Expense (Benefit) Deferred federal income tax expense (benefit) Deferred Federal Income Tax Expense (Benefit) Total federal income tax expense (benefit) Federal Income Tax Expense (Benefit), Continuing Operations Current foreign income tax expense (benefit) Current Foreign Tax Expense (Benefit) Deferred foreign income tax expense (benefit) Deferred Foreign Income Tax Expense (Benefit) Total foreign income tax expense (benefit) Foreign Income Tax Expense (Benefit), Continuing Operations Total federal and foreign income tax expense Accounts Receivable by Customer (Table Amounts) [Table] Accounts Receivables [Line Items] Accounts Receivable, after Allowance for Credit Loss [Abstract] Accounts Receivable, after Allowance for Credit Loss [Abstract] Accounts receivable, gross Accounts Receivable, before Allowance for Credit Loss, Current Allowance for doubtful accounts Accounts Receivable, Allowance for Credit Loss, Current Accounts receivable, net