For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 275

-SubTopic 10

-Section 50

-Paragraph 18

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Reference 2: http://www.xbrl.org/2003/role/presentationRef

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Long-lived assets other than financial instruments, long-term customer relationships of a financial institution, mortgage and other servicing rights, deferred policy acquisition costs, and deferred tax assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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-Topic 280

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- Definition

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)

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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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Segment and Geographic Information (Details 1) - USD ($) $ in Millions	3 Months Ended									6 Months Ended		12 Months Ended
	Jun. 30, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	$ 1,342	$ 1,290	$ 1,263	$ 1,302	$ 1,196	$ 1,206	$ 1,152	$ 1,205	$ 1,140	$ 2,615	$ 2,498	$ 5,051	$ 4,702	$ 4,270
Long-lived Assets		2,665				2,751						2,665	2,751
United States [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue												2,911	2,723	2,508
Long-lived Assets		2,117				2,206						2,117	2,206
European region [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue												1,316	1,226	1,067
Long-lived Assets		430				432						430	432
Asia [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue												528	483	453
Long-lived Assets		54				59						54	59
Rest of the world [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue												296	270	$ 242
Long-lived Assets		$ 64				$ 54						$ 64	$ 54
Geographic Concentration Risk [Member] \| Revenue [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Concentration risk												100.00%	100.00%	100.00%
Geographic Concentration Risk [Member] \| Revenue [Member] \| United States [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Concentration risk												58.00%	58.00%	59.00%
Geographic Concentration Risk [Member] \| Revenue [Member] \| European region [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Concentration risk												26.00%	26.00%	25.00%
Geographic Concentration Risk [Member] \| Revenue [Member] \| Asia [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Concentration risk												10.00%	10.00%	11.00%
Geographic Concentration Risk [Member] \| Revenue [Member] \| Rest of the world [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Concentration risk												6.00%	6.00%	5.00%
Geographic Concentration Risk [Member] \| Long-lived Assets [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Concentration risk												100.00%	100.00%
Geographic Concentration Risk [Member] \| Long-lived Assets [Member] \| United States [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Concentration risk												80.00%	80.00%
Geographic Concentration Risk [Member] \| Long-lived Assets [Member] \| European region [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Concentration risk												16.00%	16.00%
Geographic Concentration Risk [Member] \| Long-lived Assets [Member] \| Asia [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Concentration risk												2.00%	2.00%
Geographic Concentration Risk [Member] \| Long-lived Assets [Member] \| Rest of the world [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Concentration risk												2.00%	2.00%