Segments - Revenue Reconciliation (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Revenue
Revenue	$ 18,028	$ 18,756	$ 55,370	$ 57,830
Business Segments
Revenue
Revenue	19,462	19,914	59,065	61,492
Other
Revenue
Other - divested businesses	48	432	754	1,335
Other revenue	59	62	190	176
Revenue	107	493	944	1,511
Internal transactions
Revenue
Revenue	$ (1,541)	$ (1,652)	$ (4,638)	$ (5,173)

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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