Segment Information (Details) $ in Millions		3 Months Ended	6 Months Ended
Jan. 10, 2017 segment	Jun. 30, 2017 USD ($)	Jun. 30, 2016 USD ($)	Jun. 30, 2017 USD ($)	Jun. 30, 2017	Jun. 30, 2016 USD ($)
Segment information
Number of reportable segments (segments)	2				2
Revenues		$ 4,090	$ 4,398	$ 8,299		$ 8,799
Expenses		3,723	3,751	7,301		7,464
Total reportable segment income		367	647	998		1,335
Operating segments
Segment information
Revenues		3,617	3,929	7,385		7,860
Expenses		1,877	2,011	3,807		3,941
Total reportable segment income		$ 1,740	$ 1,918	$ 3,578		$ 3,919
Margin percentage (percent)		48.00%	49.00%	48.00%		50.00%
Enterprise
Segment information
Revenues		$ 2,215	$ 2,435	$ 4,571		$ 4,877
Expenses		1,285	1,372	2,615		2,691
Total reportable segment income		$ 930	$ 1,063	$ 1,956		$ 2,186
Margin percentage (percent)		42.00%	44.00%	43.00%		45.00%
Consumer
Segment information
Revenues		$ 1,402	$ 1,494	$ 2,814		$ 2,983
Expenses		592	639	1,192		1,250
Total reportable segment income		$ 810	$ 855	$ 1,622		$ 1,733
Margin percentage (percent)		58.00%	57.00%	58.00%		58.00%

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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/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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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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