Segments (Revenue by segments) (Details 2) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Revenue
Revenue	$ 19,280	$ 22,397	$ 59,682	$ 68,680
Total Segments
Revenue
Revenue	19,219	22,305	59,520	68,387
Total reportable segments \| Total Segments
Revenue
Revenue	21,019	24,334	65,203	74,635
Eliminations of internal transactions \| Total Segments
Revenue
Revenue	(1,800)	(2,029)	(5,683)	(6,248)
Other revenue
Revenue
Revenue	$ 60	$ 92	$ 162	$ 292

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).

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

Name:	us-gaap_Revenues
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration