The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 45

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-URI http://asc.fasb.org/extlink&oid=6388964&loc=d3e16225-109274

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 2

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-URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16323-109275

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Intangible Assets (Details Textual) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Intangible Assets with Definite Lives:
Assets classified as held for sale	$ 5	$ 1
Amortization expense	$ 7us-gaap_AmortizationOfIntangibleAssets	$ 7us-gaap_AmortizationOfIntangibleAssets	$ 8us-gaap_AmortizationOfIntangibleAssets
Customer relationships
Intangible Assets with Definite Lives:
Weighted average amortization period, in years	10 years
Other
Intangible Assets with Definite Lives:
Weighted average amortization period, in years	11 years