Environmental Matters Environmental Remediation Obligations [Abstract] Amount Authorized Stock Repurchase Program, Authorized Amount Customer [Domain] Customer [Domain] Other customers Other Customers [Member] US state and local government and US commercial customers. 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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] Debt Instruments [Abstract] Debt Instruments [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. 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Basic earnings per share Earnings Per Share, Basic Gain on sale of business Gain on sale of business Gain (Loss) on Disposition of Business Document Type Document Type Accelerated Share Repurchase, Payment Accelerated Share Repurchase, Payment Accelerated Share Repurchase, Payment 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] Diluted earnings per share Earnings Per Share, Diluted [Abstract] Entity Current Reporting Status Entity Current Reporting Status Nonvested Restricted Stock Shares Activity [Table Text Block] Schedule of Nonvested Share Activity [Table Text Block] Commercial Paper [Member] Commercial Paper [Member] Other operating activities, net Other Noncash Income (Expense) Site Contingency [Line Items] Site Contingency [Line Items] 2022 Note, Interest Rate, Stated Percentage 2022 Note, Interest Rate, Stated Percentage 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[Abstract] Accounting Changes and Error Corrections [Abstract] September 2015 Share Repurchase Program Original Authorization September 2015 Share Repurchase Original Authorization [Member] September 2015 Share Repurchase Original Authorization [Member] Minimum [Member] Minimum [Member] Inventoried costs, net Inventory, Net of Allowances, Customer Advances and Progress Billings Line of Credit Outstanding Long-term Line of Credit Schedule of Revenues from External Customers and Long-Lived Assets [Table] Schedule of Revenues from External Customers and Long-Lived Assets [Table] Balance Sheet Location [Domain] Balance Sheet Location [Domain] False Claims Act False Claims Act [Member] False Claims Act [Member] Preferred Stock, Shares Authorized Preferred Stock, Shares Authorized Gain contingency, unrecorded amount Gain Contingency, Unrecorded Amount Non-operating FAS pension benefit Net FAS (non-service) Pension Benefit (Expense) Net FAS (non-service) Pension Benefit (Expense) January 2021 Share Repurchase Original Authorization [Member] January 2021 Share Repurchase Original Authorization [Member] January 2021 Share Repurchase Original Authorization Trading Symbol Trading Symbol 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] Deferred tax assets Deferred Income Tax Assets, Net General and administrative expenses General and Administrative Expense Revision of Prior Period [Axis] Revision of Prior Period [Axis] STOCK COMPENSATION PLANS AND OTHER COMPENSATION ARRANGEMENTS Share-based Payment Arrangement [Text Block] Cash dividends paid Payments of Ordinary Dividends, Common Stock Accounting Policies [Abstract] Accounting Policies [Abstract] Common stock, $1 par value; 800,000,000 shares authorized; issued and 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Revenue from External Customers by Geographic Areas Revenue from External Customers by Geographic Areas [Table Text Block] Investments in Marketable Securities Marketable Securities, Policy [Policy Text Block] 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 All other All Other - Geographic Region [Domain] All Other - Geographic Region [Domain] Entity Registrant Name Entity Registrant Name International(2) International [Member] International [Member] Components of net periodic benefit cost Schedule of Costs of Retirement Plans [Table Text Block] 2021 Note, Face Amount 2021 Note, Face Amount 2021 Note, Face Amount Unbilled receivables, net Unbilled Receivables, Current Proceeds from sale of equipment to a customer Cash flow from Sale of Equipment to a Customer Cash flow from Sale of Equipment to a Customer Cash dividends declared per share Common 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[Abstract] SEGMENT INFORMATION Segment Reporting Disclosure [Text Block] Operating income Operating income Operating income Operating Income (Loss) Defined contribution plan, employer contributions Defined Contribution Plan, Employer Discretionary Contribution Amount BASIS OF PRESENTATION Organization, Consolidation and Presentation of Financial Statements Disclosure and Significant Accounting Policies [Text Block] Disclosure Text Block Supplement [Abstract] Disclosure Text Block Supplement [Abstract] Increase (Decrease) in Stockholders' Equity [Roll Forward] Increase (Decrease) in Stockholders' Equity [Roll Forward] Cumulative translation adjustment and other, net Accumulated Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Net of Tax Change in Accounting Estimate, Type [Domain] Change in Accounting Estimate, Type [Domain] Property, Plant and Equipment [Abstract] Property, Plant and Equipment [Abstract] Stock-based compensation Share-based Payment 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Share-based Payment Arrangement [Abstract] Loss Contingency, Nature [Domain] Loss Contingency, Nature [Domain] Total liabilities Liabilities Revenue, Contract Type [Line Items] Segment Reporting, Revenue Reconciling Item [Line Items] 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 Award Type [Axis] Award Type [Axis] Financing activities Net Cash Provided by (Used in) Financing Activities [Abstract] Consolidation Items [Axis] Consolidation Items [Axis] Revenue by Major Customers by Reporting Segments Schedule of Revenue by Major Customers by Reporting Segments [Table Text Block] Total shareholders’ equity Beginning of period End of period Stockholders' Equity Attributable to Parent Common Stock, Shares, Issued Common Stock, Shares, Issued Preferred 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Repurchase Final Delivery Possible Settlement Shares City Area Code City Area Code Retained earnings Retained Earnings (Accumulated Deficit) Operating Segments [Member] Operating Segments [Member] Schedule of Defined Benefit Plans Disclosures [Table] Schedule of Defined Benefit Plans Disclosures [Table] Five Year Term [Member] [Domain] Five Year Term [Member] [Domain] Five Year Term [Member] Litigation Case [Domain] Litigation Case [Domain] Restricted Stock Units (RSUs) [Member] Restricted Stock Units (RSUs) [Member] Statement of Stockholders' Equity [Abstract] Statement of Stockholders' Equity [Abstract] Revision of Prior Period [Domain] Revision of Prior Period [Domain] Revenue from External Customers by Contract Type Reconciliation of Revenue from Segments to Consolidated [Table Text Block] Share Repurchase Program [Axis] Share Repurchase Program [Axis] Amendment Flag Amendment Flag Schedule of Change in Accounting Estimate [Table] Schedule of Change in Accounting Estimate [Table] Change in Accounting Estimate [Line Items] Change in Accounting Estimate [Line Items] Payments to credit facilities Repayments of Lines of Credit 2021 Note, Interest Rate, Stated Percentage 2021 Note, Interest Rate, Stated Percentage 2021 Note, Interest Rate, Stated Percentage Accelerated Share Repurchase Initial Receipt Monetary Accelerated Share Repurchase Initial Receipt Monetary Accelerated Share Repurchase Initial Receipt Monetary Other Noncurrent Assets [Member] Other Noncurrent Assets [Member] Federal and foreign income tax expense Income Tax Expense (Benefit) Accounts receivable, net Accounts Receivable, after Allowance for Credit Loss, Current Asia/Pacific Asia Pacific [Member] Net proceeds from issuance of long-term debt Proceeds from Issuance of Long-term Debt Statement, Equity Components [Axis] Equity Components [Axis] Fair Value Disclosures [Abstract] Fair Value Disclosures [Abstract] Total current assets Assets, Current Entity File Number Entity File Number Statement of Financial Position [Abstract] Statement of Financial Position [Abstract] Contracts Accounted for under Percentage of Completion [Member] Contracts Accounted for under Percentage of Completion [Member] Schedule of Change in Accounting Estimate [Table Text Block] Schedule of Change in Accounting Estimate [Table Text Block] Long-term Debt, Current Maturities Long-term Debt, Current Maturities Product and Service [Axis] Product and Service [Axis] Fair Value, by Balance Sheet Grouping [Table] Fair Value, by Balance Sheet Grouping [Table] Entity Incorporation, State or Country Code Entity Incorporation, State or Country Code Entity Small Business Entity Small Business Preferred Stock, Par Value Preferred Stock, Par or Stated Value Per Share Equity Component [Domain] Equity Component [Domain] Other Stockholders' Equity, Other Foreign Currency Cash Flow Hedge Derivative at Fair Value, Net Foreign Currency Cash Flow Hedge Derivative at Fair Value, Net Statement [Line Items] Statement [Line 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[Abstract] Geographical [Axis] Geographical [Axis] Nondeductible Goodwill, Divested Business Nondeductible Goodwill, Divested Business Nondeductible Goodwill, Divested Business Change in Accounting Estimate by Type [Axis] Change in Accounting Estimate by Type [Axis] Diluted earnings per share Earnings Per Share, Diluted Weighted-average common shares outstanding, in millions Weighted Average Number of Shares Outstanding, Basic Segments [Domain] Segments [Domain] Product [Member] Product [Member] Service cost Defined Benefit Plan, Service Cost Space Systems [Member] Space Systems [Member] Space Systems reporting segment. Intangible assets, net Intangible Assets, Net (Excluding Goodwill) Comprehensive income Comprehensive Income (Loss), Net of Tax, Attributable to Parent Pretax profit of the IT and mission support services business Income (Loss) from Individually Significant Component Disposed of or Held-for-sale, Excluding Discontinued Operations, Attributable to Parent, before Income Tax Fixed-price [Member] Fixed-price Contract [Member] Net cash (used in) provided by financing activities Net Cash Provided by (Used in) Financing Activities Vesting period Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period Other Noncurrent Liabilities [Member] Other Noncurrent Liabilities [Member] FAIR VALUE OF FINANCIAL INSTRUMENTS Fair Value Disclosures [Text Block] Trade accounts payable Accounts Payable, Current Accelerated share repurchase initial receipt shares Accelerated share repurchase initial receipt shares Accelerated share repurchase initial receipt shares Depreciation and amortization Depreciation, Depletion and Amortization Threatened Litigation Threatened Litigation [Member] Revenue, Major Customer [Line Items] Revenue, Major Customer [Line Items] Dividends declared Dividends, Common Stock Accumulated other comprehensive loss AOCI Attributable to Parent [Member] Inventoried costs, net Increase (Decrease) in Inventories 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] Common Stock, Shares, Outstanding Common Stock, Shares, Outstanding Shares Retired Treasury Stock, Shares, Retired Cost of Sales Cost of Goods and Services Sold Recorded Third-Party Environmental Recoveries, Amount Recorded Third-Party Environmental Recoveries, Amount Income Taxes Receivable Income Taxes Receivable Divestiture of IT services business Proceeds from Divestiture of Businesses Cash Performance Units Cash Performance Units [Member] Cash performance units. Change in Contract with Customer, Liability [Abstract] Change in Contract with Customer, Liability [Abstract] United States Postal Service United States Postal Service [Member] United States Postal Service [Member] Interest expense Interest and Debt Expense Loss Contingencies Loss Contingencies [Line Items] Property, plant and equipment, net of accumulated depreciation of $6,640 for 2021 and $6,335 for 2020 Property, Plant and Equipment, Net Total operating costs and expenses Operating Expenses Other non-current liabilities Other Liabilities, Noncurrent Fiscal Period Policy Fiscal Period, Policy [Policy Text Block] Marketable Securities Marketable Securities Payments of long-term debt Repayments of Long-term Debt Earnings Per Share [Abstract] Earnings Per Share [Abstract] Document Quarterly Report Document Quarterly Report Sales Revenues Other Current Liabilities [Member] Other Current Liabilities [Member] Line of Credit Facility [Table] Line of Credit Facility [Table] Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Long-term debt, net of current portion of $6 for 2021 and $742 for 2020 Long-term Debt, Excluding Current Maturities Europe Europe [Member] Earnings Per Share, Basic and Diluted [Abstract] Earnings Per Share, Basic and Diluted [Abstract] Document Fiscal Period Focus Document Fiscal Period Focus Effective income tax rate Effective Income Tax Rate Reconciliation, Percent Loss Contingency, Estimate of Possible Loss Loss Contingency, Estimate of Possible Loss Accelerated Share Repurchase Remaining Amount Accelerated Share Repurchase Remaining Amount Accelerated Share Repurchase Remaining Amount Accelerated Share Repurchase Share Price Accelerated Share Repurchase Share Price Accelerated Share Repurchase Share Price 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] Unbilled receivables, net Contract with Customer, Asset, after Allowance for Credit Loss, Current Mission Systems [Member] Mission Systems [Member] Mission Systems reporting segment. United States UNITED STATES Common Stock, Par or Stated Value Per Share Common Stock, Par or Stated Value Per Share Defined Benefit Plan Disclosure [Line Items] Defined Benefit Plan Disclosure [Line Items] Statement of Comprehensive Income [Abstract] Statement of Comprehensive Income [Abstract] Other financing activities, net Proceeds from (Payments for) Other Financing Activities Operating costs and expenses Cost of Goods and Services Sold [Abstract] Entity Central Index Key Entity Central Index Key Security Exchange Name Security Exchange Name Revenue from Contract with Customer Revenue from Contract with Customer [Policy Text Block] U.S. government(1) US Government [Member] US Government [Member] Weighted-average diluted shares outstanding, in millions Weighted Average Number of Shares Outstanding, Diluted Other comprehensive loss, net of tax Other comprehensive loss, net of tax Other Comprehensive Income (Loss), Net of Tax Fair Value, Recurring [Member] Fair Value, Recurring [Member] Commercial Paper, Maximum Borrowing Capacity Commercial Paper, Maximum Borrowing Capacity Commercial Paper, Maximum Borrowing Capacity INCOME TAXES Income Tax Disclosure [Text Block] Long-term Debt, Type [Axis] Long-term Debt, Type [Axis] Current Fiscal Year End Date Current Fiscal Year End Date Reconciliation of Revenue from Segments to Consolidated [Table] Reconciliation of Revenue from Segments to Consolidated [Table] EARNINGS PER SHARE, SHARE REPURCHASES AND DIVIDENDS ON COMMON STOCK Stockholders' Equity Note Disclosure [Text Block] Fair Value of Long-term Debt Fair Value of Financial Instruments, Policy [Policy Text Block] Statement of Cash Flows [Abstract] Statement of Cash Flows [Abstract] Credit Facility [Axis] Credit Facility [Axis] Net cash provided by (used in) investing activities Net Cash Provided by (Used in) Investing Activities Sales and operating income by segment Reconciliation of Operating Profit (Loss) from Segments to Consolidated [Table Text Block] Accumulated Depreciation Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment Loss Contingency, Range of Possible Loss, Portion Not Accrued Loss Contingency, Range of Possible Loss, Portion Not Accrued Operating activities Net Cash Provided by (Used in) Operating Activities [Abstract] Principles of Consolidation Consolidation, Policy [Policy Text Block] Total current liabilities Liabilities, Current Payments of employee taxes withheld from share-based awards Payment, Tax Withholding, Share-based Payment Arrangement Intersegment sales Intersegment Eliminations [Member] Litigation Status [Domain] Litigation Status [Domain] Line of Credit Facility, Maximum Borrowing Capacity Line of Credit Facility, Maximum Borrowing Capacity Loss Contingencies [Table] Loss Contingencies [Table] Segment Reporting Information [Line Items] Segment Reporting Information [Line Items] Entity Address, Postal ZIP Code Entity Address, Postal Zip Code Line of Credit Facility [Line Items] Line of Credit Facility [Line Items] Assets of disposal group held for sale Disposal Group, Including Discontinued Operation, Assets, Current Debt Instrument, Name [Domain] Debt Instrument, Name [Domain] Title of 12(b) Security Title of 12(b) Security Prepaid expenses and other current assets Other Assets, Current Statement [Table] Statement [Table] Accrual for Environmental Remediation Costs Accrual for Environmental Loss Contingencies New Accounting Pronouncements, Policy New Accounting Pronouncements, Policy [Policy Text Block] 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 Gain Contingency, Nature [Domain] Gain Contingency, Nature [Domain] Statistical Measurement [Axis] Statistical Measurement [Axis] Prior Service Credit Tax Expense Prior Service Cost Tax Expense Prior Service Cost Tax Expense Stockholders' Equity Note [Abstract] Stockholders' Equity Note [Abstract] Goodwill Goodwill Operating activities Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] Pension Benefits Pension Plan [Member] Share Repurchases - Notes to Table Share Repurchases Table Abstract Share Repuchase Table Footnotes, detail tags 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]