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Number Of Common Stock Exchanged

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Number Of Common Stock Exchanged, Conversion Ratio

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Percentage of Reduction in Common Stock Outstanding

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Proceeds From Divestiture Of Businesses, Financing Activities

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The charge against earnings in the period for known and estimated costs of termination benefits provided to current employees that are voluntarily and involuntarily terminated under a benefit arrangement associated with exit from or disposal of business activities or restructurings pursuant to a duly authorized plan, excluding costs or losses pertaining to an entity newly acquired in a business combination or a discontinued operation as defined by generally accepted accounting principles and costs associated with one-time termination benefits.

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Amount of net assets (liabilities).

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This element represents the fair value of the noncontrolling interest in the acquiree at the acquisition date.

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The amount of identifiable intangible assets recognized as of the acquisition date.

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Amount of liabilities assumed at the acquisition date.

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Percentage of voting equity interests acquired in a business combination achieved in stages, including equity interests in the acquiree held by the acquirer immediately before the acquisition date and acquired at the acquisition date.

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Percentage of equity in the acquiree held by the acquirer immediately before the acquisition date in a business combination.

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In a business combination achieved in stages, this element represents the amount of net gain (loss) recognized by the entity as a result of remeasuring to fair value the equity interest in the acquiree it held before the business combination.

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Indirect cost incurred related to good produced and service rendered.

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Face (par) amount of debt instrument at time of issuance.

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Remaining amortization period of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount of gain (loss) from sale and disposal of integrated set of activities and assets capable of being conducted and managed for purpose of providing return in form of dividend, lower cost, or other economic benefit to investor, owner, member and participant.

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Amount of noncash income (expense), classified as other, from discontinued operations.

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Amount of cost (reversal of cost) for pension benefits. Excludes other postretirement benefits.

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Equity impact of the value of stock that has been repurchased and retired during the period. The excess of the purchase price over par value can be charged against retained earnings (once the excess is fully allocated to additional paid in capital).

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Acquisition and Divestitures - Additional Information (Detail) $ in Millions			3 Months Ended	8 Months Ended	12 Months Ended			28 Months Ended
	Aug. 24, 2016 USD ($)	Aug. 16, 2016 USD ($) shares	Dec. 31, 2017 USD ($)	Aug. 23, 2016	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2018
Acquisitions And Divestitures [Line Items]
One-time special cash payment received from Abacus		$ 1,800			$ 0	$ 0	$ 1,800
Net gain on divestiture of business segment					$ 0	$ 73	1,201
Fair value of shares of common stock tendered and retired							2,497
Abacus \| Term Loan Facilities
Acquisitions And Divestitures [Line Items]
Amount of issued debt		$ 1,840
Information Systems & Global Solutions
Acquisitions And Divestitures [Line Items]
Percentage of reduction in common stock outstanding		3.00%
Net gain on divestiture of business segment		$ 1,300					1,200
Fair value of shares of common stock tendered and retired		2,500
Net book value		3,000
Other adjustments		$ 100
Information Systems & Global Solutions \| Lockheed Martin
Acquisitions And Divestitures [Line Items]
Number of common stock exchanged (in shares) \| shares		9,369,694
Conversion ratio		1
Information Systems & Global Solutions \| Continuing Operations
Acquisitions And Divestitures [Line Items]
Pension costs							54
Information Systems & Global Solutions \| Discontinued Operations
Acquisitions And Divestitures [Line Items]
Severance charges							19
Information Systems & Global Solutions \| Adjustments for
Acquisitions And Divestitures [Line Items]
Corporate overhead							(82)
Information Systems & Global Solutions \| Discontinued Operations, Disposed of by Sale
Acquisitions And Divestitures [Line Items]
Net gain on divestiture of business segment			$ 73
AWE Management Limited
Acquisitions And Divestitures [Line Items]
Ownership interest percentage owned immediately before acquisition	33.00%	33.00%
Ownership interest percentage owned subsequent acquisition	51.00%
Net liabilities	$ 32
Business combination, acquisition of less than 100 percent, noncontrolling interest, fair value	107
AWE Management Limited \| Net Earnings From Continuing Operations
Acquisitions And Divestitures [Line Items]
Gain (loss) associated with obtaining control of AWE							104
AWE Management Limited \| Customer relationships
Acquisitions And Divestitures [Line Items]
Intangible assets	$ 243
Acquired finite-lived intangible assets are amortized	8 years
Pre-tax gain recognized in operating results of Space System business segment \| AWE Management Limited \| Space
Acquisitions And Divestitures [Line Items]
Gain (loss) associated with obtaining control of AWE							127
Deferred tax liabilities at corporate office \| AWE Management Limited
Acquisitions And Divestitures [Line Items]
Gain (loss) associated with obtaining control of AWE							$ 23
Net Sales \| AWE Management Limited \| Segment Concentration Risk \| Space
Acquisitions And Divestitures [Line Items]
Concentration percentage					100.00%			100.00%
Net Sales \| AWE Management Limited \| Equity Method Investment Risk \| Space
Acquisitions And Divestitures [Line Items]
Concentration percentage				0.00%
Operating profit \| AWE Management Limited \| Segment Concentration Risk \| Space
Acquisitions And Divestitures [Line Items]
Concentration percentage					51.00%		51.00%	51.00%
Net Earnings \| AWE Management Limited \| Equity Method Investment Risk \| Space
Acquisitions And Divestitures [Line Items]
Concentration percentage				33.00%