Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

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-Subparagraph (SX 210.5-02.14)

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

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 14

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- Definition

The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

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- Definition

Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (b)

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-Section S99

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-Subparagraph (SX 210.5-02.13)

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- Definition

Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

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-Topic 210

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-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.13)

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

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Other Financial Data - Components of Fixed Assets, Net (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Fixed Assets, net
Fixed assets, gross	$ 2,311us-gaap_PropertyPlantAndEquipmentGross	$ 2,289us-gaap_PropertyPlantAndEquipmentGross
Less: Accumulated depreciation	1,546	1,498
Fixed assets, net	765us-gaap_PropertyPlantAndEquipmentNet	791us-gaap_PropertyPlantAndEquipmentNet
Depreciation expense including software amortization	242	240	232
Software [Member]
Fixed Assets, net
Fixed assets, gross	1,020	997
Leasehold improvements [Member]
Fixed Assets, net
Fixed assets, gross	413	434
Computer equipment [Member]
Fixed Assets, net
Fixed assets, gross	347	341
Furniture, fixtures and equipment [Member]
Fixed Assets, net
Fixed assets, gross	313	323
Construction in progress [Member]
Fixed Assets, net
Fixed assets, gross	94	70
Other [Member]
Fixed Assets, net
Fixed assets, gross	$ 124	$ 124