Segment Information - Results (Details) $ in Millions		3 Months Ended	9 Months Ended
Nov. 01, 2017 segment	Sep. 30, 2018 USD ($)	Sep. 30, 2017 USD ($)	Sep. 30, 2018 USD ($) category segment	Sep. 30, 2017 USD ($)
Segment Reporting Information [Line Items]
Number of reportable segments \| segment	2			2
Revenues		$ 5,818	$ 4,034	$ 17,665	$ 12,333
Expenses		4,924	3,547	15,254	10,848
OPERATING INCOME		894	487	$ 2,411	1,485
Number of categories of products and services \| category				5
Business
Segment Reporting Information [Line Items]
Revenues		4,285	2,425	$ 13,033	7,485
Expenses		2,446	1,537	7,540	4,641
OPERATING INCOME		$ 1,839	$ 888	$ 5,493	$ 2,844
Margin percentage		43.00%	37.00%	42.00%	38.00%
Consumer
Segment Reporting Information [Line Items]
Revenues		$ 1,355	$ 1,420	$ 4,086	$ 4,304
Expenses		523	660	1,704	1,931
OPERATING INCOME		$ 832	$ 760	$ 2,382	$ 2,373
Margin percentage		61.00%	54.00%	58.00%	55.00%
Operating segments
Segment Reporting Information [Line Items]
Revenues		$ 5,640	$ 3,845	$ 17,119	$ 11,789
Expenses		2,969	2,197	9,244	6,572
OPERATING INCOME		$ 2,671	$ 1,648	$ 7,875	$ 5,217
Margin percentage		47.00%	43.00%	46.00%	44.00%
Operating segments \| Business
Segment Reporting Information [Line Items]
Revenues		$ 4,285	$ 2,425	$ 13,033	$ 7,485
Operating segments \| Consumer
Segment Reporting Information [Line Items]
Revenues		$ 1,355	$ 1,420	$ 4,086	$ 4,304

Represents the number of categories in which the entity categorizes the products and services.

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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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