Segment Information (Details) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2016 USD ($)	Jun. 30, 2015 USD ($)	Jun. 30, 2016 USD ($) segment	Jun. 30, 2015 USD ($)
Segment information
Revenues	$ 4,398	$ 4,419	$ 8,799	$ 8,870
Expenses	3,748	3,870	7,455	7,672
OPERATING INCOME	650	549	$ 1,344	1,198
Number of reportable segments (segments) \| segment			2
Operating segments
Segment information
Revenues	4,091	4,161	$ 8,184	8,355
Expenses	2,141	2,140	4,192	4,211
OPERATING INCOME	$ 1,950	$ 2,021	$ 3,992	$ 4,144
Margin percentage (percent)	48.00%	49.00%	49.00%	50.00%
Business
Segment information
Revenues	$ 2,597	$ 2,658	$ 5,201	$ 5,355
Expenses	1,487	1,504	2,914	2,967
OPERATING INCOME	$ 1,110	$ 1,154	$ 2,287	$ 2,388
Margin percentage (percent)	43.00%	43.00%	44.00%	45.00%
Business \| Operating expense \| Restatement adjustment
Segment information
Expenses		$ (21)		$ (42)
Consumer
Segment information
Revenues	$ 1,494	1,503	$ 2,983	3,000
Expenses	654	636	1,278	1,244
OPERATING INCOME	$ 840	$ 867	$ 1,705	$ 1,756
Margin percentage (percent)	56.00%	58.00%	57.00%	59.00%
Consumer \| Operating expense \| Restatement adjustment
Segment information
Expenses		$ 19		$ 38

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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.

+ References

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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.

+ References

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+ References

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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/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=26872669&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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