Restructuring Charges and Other Corporate Matters (Restructuring and Other Corporate Matters) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Restructuring Cost and Reserve [Line Items]
Restructuring charges	$ 202	$ 128
Merger-related costs	31	0
Other corporate matters	0	50
Restructuring and other corporate matters	233	178
Depreciation of abandoned technology	12	0
Severance [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring charges	176	98
Exit costs [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring charges	$ 26	$ 30

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 expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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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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Amount of accelerated depreciation charged against earnings associated with exit from or disposal of business activities or restructuring plan.

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Other Corporate Matters, Costs

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Restructuring and other corporate matters

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