Land, Buildings, Equipment and Software, Net (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2017	Dec. 31, 2018
Property, Plant, Equipment and Software [Line Items]
Product software	$ 22	$ 18
Land, buildings and equipment, gross	1,076	1,222
Accumulated depreciation	(819)	(894)
Land, Buildings and Equipment, Net	257	328
Land [Member]
Property, Plant, Equipment and Software [Line Items]
Land	3	2
Building and building equipment [Member]
Property, Plant, Equipment and Software [Line Items]
Buildings and Improvements, Gross	17	7
Leasehold Improvements [Member]
Property, Plant, Equipment and Software [Line Items]
Leasehold Improvements, Gross	247	246
Office furniture and equipment [Member]
Property, Plant, Equipment and Software [Line Items]
Furniture and Fixtures, Gross	784	901
Other [Member]
Property, Plant, Equipment and Software [Line Items]
Other Land, Building, Equipment and Software	1	2
Construction in progress [Member]
Property, Plant, Equipment and Software [Line Items]
Construction in Progress, Gross	$ 24	$ 64
Minimum [Member] \| Building and building equipment [Member]
Property, Plant, Equipment and Software [Line Items]
Property, Plant and Equipment, Useful Life	25 years
Minimum [Member] \| Office furniture and equipment [Member]
Property, Plant, Equipment and Software [Line Items]
Property, Plant and Equipment, Useful Life	3 years
Minimum [Member] \| Other [Member]
Property, Plant, Equipment and Software [Line Items]
Property, Plant and Equipment, Useful Life	4 years
Maximum [Member] \| Building and building equipment [Member]
Property, Plant, Equipment and Software [Line Items]
Property, Plant and Equipment, Useful Life	50 years
Maximum [Member] \| Office furniture and equipment [Member]
Property, Plant, Equipment and Software [Line Items]
Property, Plant and Equipment, Useful Life	15 years
Maximum [Member] \| Other [Member]
Property, Plant, Equipment and Software [Line Items]
Property, Plant and Equipment, Useful Life	20 years

Other Land, Building, Equipment and Software

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- Definition

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

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Amount before accumulated depreciation of building structures held for productive use including addition, improvement, or renovation to the structure, including, but not limited to, interior masonry, interior flooring, electrical, and plumbing.

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Unamortized costs incurred for development of computer software, which is to be sold, leased or otherwise marketed, after establishing technological feasibility through to the general release of the software products. Excludes capitalized costs of developing software for internal use.

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Amount of structure or a modification to a structure under construction. Includes recently completed structures or modifications to structures that have not been placed into service.

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- Definition

Amount before accumulated depreciation of equipment commonly used in offices and stores that have no permanent connection to the structure of a building or utilities. Examples include, but are not limited to, desks, chairs, tables, and bookcases.

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Amount before accumulated depletion of real estate held for productive use, excluding land held for sale.

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Amount before accumulated depreciation of additions or improvements to assets held under a lease arrangement.

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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.

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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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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.

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

+ References

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