Segment Information (Narrative) (Details) $ in Millions	12 Months Ended
Dec. 31, 2019 USD ($) Segment	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Segment Reporting Information [Line Items]
Number of operating segments \| Segment	5
Revenue	$ 39,350	$ 36,193	$ 30,973
Earnings from continuing operations before income tax	$ 4,202	$ 4,085	$ 4,077
Long-lived assets of non-U.S. operations percent of total	4.00%	3.00%	5.00%
International Operations
Segment Reporting Information [Line Items]
Revenue	$ 4,400	$ 4,200	$ 3,700
Earnings from continuing operations before income tax	600	$ 578	$ 550
CSRA
Segment Reporting Information [Line Items]
One-time charges associated with costs to complete acquisition	$ 45

Entity Wide Disclosure On Geographic Areas Long Lived Assets In Individual Foreign Countries Percentage

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- Definition

This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

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Amount of income (loss) from continuing operations before deduction of income tax expense (benefit) and income (loss) attributable to noncontrolling interest, and addition of income (loss) from equity method investments.

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- Definition

Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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