Basis of Presentation Basis of Presentation (Details) - USD ($) $ in Millions	Jun. 30, 2015	Dec. 31, 2014
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Investments	$ 142	$ 143

The total amount of investments that are intended to be held for an extended period of time (longer than one operating cycle).

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.12)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Name:	us-gaap_LongTermInvestments
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant