Segments - Revenue Reconciliation (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Revenue
Revenue	$ 77,147	$ 79,591	$ 79,139
Business Segments
Revenue
Revenue	82,419	84,386	83,329
Other
Revenue
Other - divested businesses	786	1,810	2,041
Other revenue	162	207	171
Internal transactions
Revenue
Revenue	$ (6,220)	$ (6,813)	$ (6,401)

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process, excluding amounts attributable to disposal groups.

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Amount of revenue attributable to disposal group, including, but not limited to, discontinued operation.

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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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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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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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