Share-based Payment Arrangement [Abstract] Nonvested Restricted Stock Shares Activity [Table Text Block] Schedule of Nonvested Share Activity [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 Cash Flows [Abstract] Statement [Table] Statement [Table] Restatement [Axis] Restatement [Axis] Restatement [Domain] Restatement [Domain] Statement [Line Items] Statement [Line Items] Operating activities Net Cash Provided by (Used in) Operating Activities [Abstract] Operating activities Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] Net earnings Net Income (Loss) Attributable to Parent Adjustments to reconcile to net cash provided by operating activities: Adjustments, Noncash Items, to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] Depreciation and amortization Depreciation, Depletion and Amortization 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 Payments to Acquire Property, Plant, and Equipment Other, 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 payments to credit facilities Repayments of Lines of Credit Net 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, net Proceeds from (Payments for) Other Financing Activities Net cash used in financing activities Net Cash Provided by (Used in) Financing Activities Decrease in cash and cash equivalents Cash and Cash Equivalents, Period Increase (Decrease) Cash and cash equivalents, beginning of year Cash and Cash Equivalents, at Carrying Value Cash and cash equivalents, end of period Income Tax Disclosure [Abstract] INCOME TAXES Income Tax Disclosure [Text Block] Segment Reporting [Abstract] SEGMENT INFORMATION Segment Reporting Disclosure [Text Block] Commitments and Contingencies Disclosure [Abstract] Environmental Matters Environmental Remediation Obligations [Abstract] Environmental Contingency [Table] Site Contingency [Table] Loss Contingencies by Nature of Contingency [Axis] Loss Contingency Nature [Axis] Loss Contingency, Nature [Domain] Loss Contingency, Nature [Domain] Environmental Issue [Member] Environmental Issue [Member] Statistical Measurement [Axis] Statistical Measurement [Axis] Statistical Measurement [Domain] Statistical Measurement [Domain] Maximum [Member] Minimum Minimum [Member] 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] Other Current Assets [Member] Other Current Assets [Member] Other Noncurrent Assets [Member] Other Noncurrent Assets [Member] Site Contingency [Line Items] Site Contingency [Line Items] Loss Contingency, Estimate of Possible Loss Loss Contingency, Estimate of Possible Loss Accrual for Environmental Remediation Costs Accrual for Environmental Loss Contingencies Recorded Third-Party Environmental Recoveries, Amount Recorded Third-Party Environmental Recoveries, Amount Financial Arrangements Other Commitments [Abstract] Standby Unused 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 Line of Credit Facility Line of Credit Facility [Abstract] Line of Credit Facility [Table] Line of Credit Facility [Table] 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] Long-term Debt, Type [Axis] Long-term Debt, Type [Axis] Long-term Debt, Type [Domain] Long-term Debt, Type [Domain] Business Acquisition [Axis] Business Acquisition [Axis] Business Acquisition, Acquiree [Domain] Business Acquisition, Acquiree [Domain] Orbital ATK Orbital ATK [Member] Orbital ATK [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] Debt Instrument [Axis] Debt Instrument [Axis] Debt Instrument, Name [Domain] Debt Instrument, Name [Domain] Two Year Term [Member] [Domain] Two Year Term [Member] [Domain] Two Year Term [Member] [Domain] Five Year Term [Member] [Domain] Five Year Term [Member] [Domain] Five Year Term [Member] Line of Credit Facility [Line Items] Line of Credit Facility [Line Items] Line of Credit Facility, Maximum Borrowing Capacity Line of Credit Facility, Maximum Borrowing Capacity Debt Instrument, Covenant Compliance Debt Instrument, Covenant Compliance Commercial Paper Commercial Paper Commercial Paper, Maximum Borrowing Capacity Commercial Paper, Maximum Borrowing Capacity Commercial Paper, Maximum Borrowing Capacity Commercial Paper, Weighted Average Interest Rate Short-term Debt, Weighted Average Interest Rate, at Point in Time Commercial Paper, Term Debt Instrument, Term Line of Credit Outstanding Long-term Line of Credit Line of Credit Facility, Interest Rate During Period Line of Credit Facility, Interest Rate During Period 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 liabilities Operating Lease, Liability, Noncurrent Operating Lease, Liability Operating Lease, Liability Sales and operating income by segment Reconciliation of Operating Profit (Loss) from Segments to Consolidated [Table Text Block] Revenue by Major Customers by Reporting Segments Schedule of Revenue by Major Customers by Reporting Segments [Table Text Block] Revenue from External Customers by Contract Type Reconciliation of Revenue from Segments to Consolidated [Table Text Block] Revenue from External Customers by Geographic Areas Revenue from External Customers by Geographic Areas [Table Text Block] Organization, Consolidation and Presentation of Financial Statements [Abstract] Accounting Changes and Error Correction [Abstract] Accounting Changes and Error Corrections [Abstract] Schedule of Change in Accounting Estimate [Table] Schedule of Change in Accounting Estimate [Table] Segments [Axis] Segments [Axis] Segments [Domain] Segments [Domain] Aerospace Systems [Member] Aerospace Systems [Member] Aerospace Systems reporting segment. 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] Operating income Operating Income (Loss) Earnings Per Share, Diluted Contract with Customer, Performance Obligation Satisfied in Previous Period Contract with Customer, Performance Obligation Satisfied in Previous Period Disclosure Text Block Supplement [Abstract] Loss Contingencies [Table] Loss Contingencies [Table] Maximum 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. United States Postal Service United States Postal Service [Member] United States Postal Service [Member] Solystic Matter [Member] Solystic Matter [Member] Solystic Matter [Member] Gain Contingencies by 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 [Domain] Litigation Case [Domain] U.S. government (1) US Government [Member] US Government [Member] False Claims Act False Claims Act [Member] False Claims Act [Member] Litigation Status [Axis] Litigation Status [Axis] Litigation Status [Domain] Litigation Status [Domain] Threatened Litigation Threatened Litigation [Member] Loss Contingencies Loss Contingencies [Line Items] Contract award Contract Award Total Contract Award Unbilled receivables, net Unbilled Receivables, Current Gain contingency, unrecorded amount Gain Contingency, Unrecorded Amount 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 Loss Contingency, Number of Additional Defendants Loss Contingency, Number of Defendants Schedule of Revenues from External Customers and Long-Lived Assets [Table] Schedule of Revenues from External Customers and Long-Lived Assets [Table] Consolidation Items [Axis] Consolidation Items [Axis] Consolidation Items [Domain] Consolidation Items [Domain] Operating Segments [Member] Operating Segments [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 Intersegment Sales [Member] Intersegment Sales [Member] Innovation Systems [Member] Innovation Systems [Member] Innovation Systems reporting segment Mission Systems [Member] Mission Systems [Member] Mission Systems reporting segment. Technology Services [Member] Technology Services [Member] Technology Services reporting segment. Revenue, Geographic Location [Line Items] Revenues from External Customers and Long-Lived Assets [Line Items] Sales Revenues Concentration Risk, Percentage Concentration Risk, Percentage 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] International (2) International [Member] International [Member] 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] Business Combinations [Abstract] Schedule of Business Acquisitions, by Acquisition [Table] Schedule of Business Acquisitions, by Acquisition [Table] Business Acquisition [Line Items] Business Acquisition [Line Items] Pro forma sales Business Acquisition, Pro Forma Revenue Pro forma net earnings Business Acquisition, Pro Forma Net Income (Loss) Pro forma diluted earnings per share Business Acquisition, Pro Forma Earnings Per Share, Diluted 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 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 amortization on net actuarial losses and prior service costs and pension/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 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) income AOCI Attributable to Parent [Member] Increase (Decrease) in Stockholders' Equity [Roll Forward] Increase (Decrease) in Stockholders' Equity [Roll Forward] Beginning of period 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 Dividends declared Dividends, Common Stock Stock compensation Shares Issued, Value, Share-based Payment Arrangement, after Forfeiture Other comprehensive loss, net of tax Other Comprehensive Income (Loss), Net of Tax End of period Cash dividends declared per share Common Stock, Dividends, Per Share, Declared Schedule of Income Tax Expense and Effective Income Tax Rates Schedule of Income Tax Expense and Effective Income Tax Rates [Table Text Block] Schedule of Income Tax Expense and Effective Income Tax Rates [Table Text Block] Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract] Prior Service Cost (Credit), after Tax Accumulated Other Comprehensive (Income) Loss, Defined Benefit Plan, Prior Service Cost (Credit), 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 prior service credit, tax expense Prior Service Cost Tax Expense Prior Service Cost Tax Expense Unamortized prior service credit, reclassified from accumulated other comprehensive loss to net earnings Other Comprehensive (Income) Loss, Defined Benefit Plan, Reclassification Adjustment from AOCI, after Tax Leases [Abstract] Lessee, Operating and Finance Leases [Text Block] Lessee, Operating Leases [Text Block] Lessee Disclosure [Abstract] Lessee Disclosure [Abstract] Equity [Abstract] EARNINGS PER SHARE, SHARE REPURCHASES AND DIVIDENDS ON COMMON STOCK Stockholders' Equity Note Disclosure [Text Block] Schedule of Segment Reporting Information, by Segment [Table] Schedule of Segment Reporting Information, by Segment [Table] Intersegment sales Intersegment Eliminations [Member] Segment Reconciling Items [Member] Segment Reconciling Items [Member] Corporate, Non-Segment [Member] Corporate, Non-Segment [Member] Segment Reporting Information [Line Items] Segment Reporting Information [Line Items] Number of reportable segments Number of Reportable Segments Operating income Net FAS (service)/ CAS pension adjustment Net FAS (service)/ CAS pension adjustment Net FAS (service)/ CAS pension adjustment Stockholders' Equity Note [Abstract] Stockholders' Equity Note [Abstract] Earnings Per Share [Abstract] Earnings Per Share [Abstract] 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] 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 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] Common stock dividends per share, declared (in dollars per share) Increase in quarterly common stock dividend (percent) Increase (Decrease) in Stock Dividend, Percentage Increase (Decrease) in Stock Dividend, Percentage 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] OPB Other Postretirement Benefits Plan [Member] Defined Benefit Plan Disclosure [Line Items] Defined Benefit Plan Disclosure [Line Items] Components of Net Periodic Benefit Cost 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) Net periodic benefit cost (benefit) Defined Benefit Plan, Net Periodic Benefit Cost (Credit) Defined benefit plan, contributions by Employer Defined Benefit Plan, Plan Assets, Contributions by Employer Defined Contribution Plan [Abstract] Defined Contribution Plan [Abstract] Defined contribution plan, employer contributions Defined Contribution Plan, Employer Discretionary Contribution Amount Statement of Financial Position [Abstract] Accumulated depreciation Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment Long-term debt, current portion 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 Principles of Consolidation Consolidation, Policy [Policy Text Block] Basis of Presentation Basis of Accounting, Policy [Policy Text Block] Fiscal Period Policy Fiscal Period, Policy [Policy Text Block] Accounting Estimates Use of Estimates, Policy [Policy Text Block] Revenue from Contract with Customer Revenue from Contract with Customer [Policy Text Block] Leases Lessee, Leases [Policy Text Block] Pension and Other Postretirement Plans Pension and Other Postretirement Plans, Policy [Policy Text Block] Earnings Per Share Earnings Per Share, Policy [Policy Text Block] Investments in Marketable Securities Marketable Securities, Policy [Policy Text Block] Derivative Financial Instruments and Hedging Activities Derivatives, Policy [Policy Text Block] Fair Value of Long-term Debt Fair Value of Financial Instruments, Policy [Policy Text Block] U.S. Government Cost Claims Government Contractors, Policy [Policy Text Block] New Accounting Pronouncements and Changes in Accounting Principles New Accounting Pronouncements and Changes in Accounting Principles [Text Block] Federal and foreign income tax expense Income Tax Expense (Benefit) Effective income tax rate Effective Income Tax Rate Reconciliation, Percent Effective Income Tax Rate Reconciliation, Tax Credit, Research, Amount Effective Income Tax Rate Reconciliation, Tax Credit, Research, Amount Effective Income Tax Rate Reconciliation, Tax Deduction, FDII, Amount 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. Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Amount Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Amount Environmental Remediation Range of Future Costs [Table] Environmental Remediation Range of Future Costs [Table] Environmental Remediation Range of Future Costs, the amount accrued within the rang and the deferred costs expected to be recoverable through overhead charges on US Government contracts [Table] Environmental Remediation Range of Future Costs [Line Items] Environmental Remediation Range of Future Costs [Line Items] [Line Items] for Environmental Remediation Range of Future Costs, the amount accrued within the range and the deferred costs expected to be recoverable through overhead charges on US Government contracts [Table] 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] Income Statement Location [Axis] Income Statement Location [Axis] Income Statement Location [Domain] Income Statement Location [Domain] Ownership [Axis] Ownership [Axis] Ownership [Domain] Ownership [Domain] Class of Stock [Axis] Class of Stock [Axis] Class of Stock [Domain] Class of Stock [Domain] 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 Information, Initial Accounting Incomplete, Adjustment, 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 Goodwill Goodwill Intangible assets Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill 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 Fair Value Disclosures [Abstract] FAIR VALUE OF FINANCIAL INSTRUMENTS Fair Value Disclosures [Text Block] Unrecognized Tax Benefits, Increase Resulting from Prior Period Tax Positions Unrecognized Tax Benefits, Increase Resulting from Prior Period Tax Positions Leases Other Supplemental Information [Abstract] Leases Other Supplemental Information [Abstract] Payments on operating leases Operating Lease, Payments Right-of-use assets obtained in exchange for new operating lease liabilities Right-of-Use Asset Obtained in Exchange for Operating Lease Liability Weighted-average remaining lease term—operating leases (in years) Operating Lease, Weighted Average Remaining Lease Term Weighted-average discount rate—operating leases Operating Lease, Weighted Average Discount Rate, Percent Change in Contract with Customer, Liability [Abstract] Contract with Customer, Liability, Revenue Recognized Contract with Customer, Liability, Revenue Recognized Revenue from Contract with Customer [Abstract] 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 Schedule of Share Repurchases, by Program [Table] September 2015 Share Repurchase Program Original Authorization December 2018 Share Repurchase Original Authorization [Member] December 2018 Share Repurchase Original Authorization [Member] December 2018 Share Repurchase Original Authorization [Member] Share Repurchase [Line Items] Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements Amount Authorized Stock Repurchase Program, Authorized Amount Shares Retired Treasury Stock, Shares, Retired Average Cost Per Share Treasury Stock Acquired, Average Cost Per Share Shares Repurchased Stock Repurchased and Retired During Period, Shares Share Repurchases - Notes to Table Share Repurchases Table Abstract Share Repuchase Table Footnotes, detail tags Shares repurchased amount Treasury Stock, Value, Acquired, Par Value Method Amount remaining under authorization for share repurchases Stock Repurchase Program, Remaining Authorized Repurchase Amount 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] INVESTIGATIONS, CLAIMS AND LITIGATION Legal Matters and Contingencies [Text Block] Text Block [Abstract] Long-term Debt, Fair Value Long-term Debt, Fair Value Debt and Lease Obligation Debt and Lease Obligation Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities, Long-term Debt Document and Entity Information [Abstract] Document and Entity Information. Entity Current Reporting Status Entity Current Reporting Status Document Type Document Type Document Fiscal Period Focus Document Fiscal Period Focus Document Quarterly Report Document Quarterly 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, Line 1 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 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 Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Award Type [Axis] Award Type [Axis] Award Type [Domain] Award Type [Domain] Restricted Stock Units (RSUs) [Member] Restricted Stock Units (RSUs) [Member] Performance Shares [Member] Performance Shares [Member] Cash Units Cash Units [Member] Cash Units [Member] Cash Performance Units Cash Performance Units [Member] Cash performance units. Cash Units and Cash Performance Units Cash Units and Cash Performance Units [Member] Cash Units and Cash Performance Units [Member] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Deferred Compensation Cash-based Arrangements, Liability, Current and Noncurrent Deferred Compensation Cash-based Arrangements, Liability, Current and Noncurrent Shares granted Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period Vesting period Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period Restricted Stock Rights and Restricted Performance Stock Rights Grant Date Aggregate Fair Value Restricted Stock Rights and Restricted Performance Stock Rights Grant Date Aggregate Fair Value Restricted Stock Rights and Restricted Performance Stock Rights Grant Date Aggregate Fair Value Lease Maturities [Abstract] Lease Maturities [Abstract] Lessee, Lease, Description [Table] Lessee, Lease, Description [Table] Minimum [Member] Maximum [Member] Lessee, Lease, Description [Line Items] Lessee, Lease, Description [Line Items] Lessee, Operating Lease, Lease Not yet Commenced, Term of Contract Lessee, Operating Lease, Lease Not yet Commenced, Term of Contract Remainder of 2019 Lessee, Operating Lease, Liability, Payments, Remainder of Fiscal Year 2020 Lessee, Operating Lease, Liability, Payments, Due Year Two 2021 Lessee, Operating Lease, Liability, Payments, Due Year Three 2022 Lessee, Operating Lease, Liability, Payments, Due Year Four 2023 Lessee, Operating Lease, Liability, Payments, Due Year Five Thereafter Lessee, Operating Lease, Liability, Payments, Due after Year Five Total lease payments Lessee, Operating Lease, Liability, Payments, Due Less: Imputed Interest Lessee, Operating Lease, Liability, Undiscounted Excess Amount Present value of operating lease liabilities Lessee, Operating Lease, Lease Not yet Commenced, Value Lessee, Operating Lease, Lease Not yet Commenced, Value Lessee, Operating Lease, Lease Not yet Commenced, Value 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 RETIREMENT BENEFITS Pension and Other Postretirement Benefits Disclosure [Text Block] Fair value information of assets and liabilities measured at fair value on a recurring basis Fair Value, by Balance Sheet Grouping [Table Text Block] Statement of Comprehensive Income [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 Sales Cost of Goods and Services Sold Operating costs and expenses Cost of Goods and Services Sold [Abstract] General and administrative expenses General and Administrative Expense 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) Other, net Other Nonoperating Income (Expense) Earnings before income taxes Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest Net earnings 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 Weighted-average diluted shares outstanding, in millions Weighted Average Number of Shares Outstanding, Diluted Net earnings (from above) Change in unamortized prior service credit, net of tax Other Comprehensive (Income) Loss, Defined Benefit Plan, Prior Service Cost (Credit), Reclassification Adjustment from AOCI, 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 Comprehensive income Comprehensive Income (Loss), Net of Tax, Attributable to Parent Fair Value, by Balance Sheet Grouping [Table] Fair Value, by Balance Sheet Grouping [Table] Derivative Instrument [Axis] Derivative Instrument [Axis] Derivative Contract [Domain] Derivative Contract [Domain] Copper [Member] Copper [Member] Copper [Member] Zinc [Member] [Domain] Zinc [Member] [Domain] Zinc [Member] [Domain] Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] Derivative, Nonmonetary Notional Amount, Mass Derivative, Nonmonetary Notional Amount, Mass 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 Derivative Instruments and Hedging Activities Disclosure [Abstract] Derivative Instruments and Hedging Activities Disclosure [Abstract] Foreign Currency Cash Flow Hedge Derivative at Fair Value, Net Foreign Currency Cash Flow Hedge Derivative at Fair Value, Net BASIS OF PRESENTATION Organization, Consolidation and Presentation of Financial Statements Disclosure and Significant Accounting Policies [Text Block] Finite-Lived Intangible Assets by Major Class [Axis] Finite-Lived Intangible Assets by Major Class [Axis] Finite-Lived Intangible Assets, Major Class Name [Domain] Finite-Lived Intangible Assets, Major Class Name [Domain] Customer Contracts [Member] Customer Contracts [Member] Customer Relationships [Member] Customer Relationships [Member] Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill Acquired Finite-lived Intangible Assets, Weighted Average Useful Life Acquired Finite-lived Intangible Assets, Weighted Average Useful Life 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 [Member] Time-and-materials Contract [Member] Fixed-price [Member] Fixed-price Contract [Member] Revenue, Contract Type [Line Items] Segment Reporting, Revenue Reconciling Item [Line Items] Business Combination Disclosure [Text Block] Business Combination 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 Schedule of Change in Accounting Estimate [Table Text Block] Schedule of Change in Accounting Estimate [Table Text Block] Accumulated Other Comprehensive Loss Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block] STOCK COMPENSATION PLANS AND OTHER COMPENSATION ARRANGEMENTS Share-based Payment Arrangement [Text Block] COMMITMENTS AND CONTINGENCIES Commitments and Contingencies Disclosure [Text Block] 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 Hierarchy and NAV [Axis] Fair Value Hierarchy and NAV [Domain] Fair Value Hierarchy and NAV [Domain] Fair Value, Inputs, Level 1 [Member] Fair Value, Inputs, Level 1 [Member] Fair Value, Inputs, Level 2 [Member] Fair Value, Inputs, Level 2 [Member] Marketable Securities Marketable Securities Derivatives Derivative Assets (Liabilities), at Fair Value, Net Components of net periodic benefit cost Schedule of Costs of Retirement Plans [Table Text Block] Employer contributions to retirement plans Schedule of Defined Benefit Plans Disclosures [Table Text Block] Assets Assets [Abstract] Cash and cash equivalents Accounts receivable, net Accounts Receivable, after Allowance for Credit Loss, Current Inventoried costs, net Inventory, Net Prepaid expenses and other current assets Other Assets, Current Total current assets Assets, Current Property, plant and equipment, net of accumulated depreciation of $5,709 for 2019 and $5,369 for 2018 Property, Plant and Equipment, Net 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 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 Customer Advances, Current Other current liabilities Other Liabilities, Current Total current liabilities Liabilities, Current Long-term debt, net of current portion of $45 for 2019 and $517 for 2018 Long-term Debt and Lease Obligation Pension and other postretirement benefit plan liabilities Liability, Defined Benefit Plan, Noncurrent Deferred tax liabilities Deferred Tax Liabilities, Net, Noncurrent Other non-current liabilities Other Liabilities, Noncurrent Total liabilities Liabilities Commitments and contingencies (Note 7) 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—168,701,653 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 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 Acquired Finite-Lived Intangible Assets by Major Class [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] Share Repurchases Class of Treasury Stock [Table Text Block]