Segments - Revenue Reconciliation (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Revenue
Revenue	$ 19,161	$ 20,003	$ 37,342	$ 39,075
Business Segments
Revenue
Revenue	20,170	21,278	39,603	41,578
Other
Revenue
Other - divested businesses	363	457	706	903
Other revenue	57	45	131	114
Revenue	420	503	837	1,017
Internal transactions
Revenue
Revenue	$ (1,430)	$ (1,778)	$ (3,097)	$ (3,521)

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).

+ References

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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