Segment Information - Results (Details) $ in Millions		3 Months Ended	6 Months Ended
Nov. 01, 2017 segment	Jun. 30, 2018 USD ($)	Jun. 30, 2017 USD ($)	Jun. 30, 2018 USD ($) category segment	Jun. 30, 2017 USD ($)
Segment Reporting Information [Line Items]
Number of reportable segments \| segment	2			2
Revenues		$ 5,902	$ 4,090	$ 11,847	$ 8,299
Expenses		5,135	3,723	10,330	7,301
OPERATING INCOME		767	367	$ 1,517	998
Number of categories of products and services \| category				5
Business
Segment Reporting Information [Line Items]
Revenues		4,365	2,470	$ 8,748	5,060
Expenses		2,524	1,538	5,094	3,104
OPERATING INCOME		$ 1,841	$ 932	$ 3,654	$ 1,956
Margin percentage		42.00%	38.00%	42.00%	39.00%
Consumer
Segment Reporting Information [Line Items]
Revenues		$ 1,352	$ 1,437	$ 2,731	$ 2,884
Expenses		569	631	1,181	1,271
OPERATING INCOME		$ 783	$ 806	$ 1,550	$ 1,613
Margin percentage		58.00%	56.00%	57.00%	56.00%
Operating segments
Segment Reporting Information [Line Items]
Revenues		$ 5,717	$ 3,907	$ 11,479	$ 7,944
Expenses		3,093	2,169	6,275	4,375
OPERATING INCOME		$ 2,624	$ 1,738	$ 5,204	$ 3,569
Margin percentage		46.00%	44.00%	45.00%	45.00%
Operating segments \| Business
Segment Reporting Information [Line Items]
Revenues		$ 4,365	$ 2,470	$ 8,748	$ 5,060
Operating segments \| Consumer
Segment Reporting Information [Line Items]
Revenues		$ 1,352	$ 1,437	$ 2,731	$ 2,884

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Represents the operating margin assigned to segments for the period.

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Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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Generally recurring costs associated with normal operations except for the portion of these expenses which can be clearly related to production and included in cost of sales or services. Includes selling, general and administrative expense.

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The net result for the period of deducting operating expenses from operating revenues.

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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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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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