Segments - Revenue Reconciliation (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Revenue
Revenue	$ 18,182	$ 19,072
Business Segments
Revenue
Revenue	19,433	20,299
Other
Revenue
Other - divested businesses	343	446
Other revenue	74	69
Revenue	417	515
Internal transactions
Revenue
Revenue	$ (1,668)	$ (1,743)

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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-Publisher FASB
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-Topic 205
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-Section 50
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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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-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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