Acquisitions and Dispositions (Stinger Ghaffarian Technologies Acquisition) (Details) - USD ($) $ in Millions		12 Months Ended
Apr. 25, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Business Acquisition [Line Items]
Goodwill		$ 1,265	$ 1,265	$ 968
Acquisition related costs		2	7	$ 0
SGT
Business Acquisition [Line Items]
Voting interests acquired	100.00%
Aggregate base consideration	$ 355
Adjustments to consideration transferred	10
Goodwill	$ 257
Acquisition related costs		2	4
Revenues contributed by acquiree		481	342
Gross profit contributed by acquiree		$ 47	$ 31

Business Combination, Consideration Transferred Before Adjustments

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Business Combination, Pro Forma Information, Gross Profit of Acquiree since Acquisition Date, Actual

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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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Percentage of voting equity interests acquired at the acquisition date in the business combination.

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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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This element represents the amount of revenue of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

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This element represents the amount of any measurement period adjustment (as defined) realized during the reporting period to items of consideration transferred in connection with a business combination for which the initial accounting was incomplete.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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