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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The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

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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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Other Financial Data - Components of Fixed Assets, Net (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Fixed Assets, net
Fixed assets, gross	$ 1,780	$ 1,733
Less: Accumulated depreciation	1,159	1,145
Fixed assets, net	621	588
Depreciation of fixed assets	172	176	$ 187
Software
Fixed Assets, net
Fixed assets, gross	727	693
Leasehold improvements
Fixed Assets, net
Fixed assets, gross	358	334
Computer equipment
Fixed Assets, net
Fixed assets, gross	250	279
Furniture, fixtures and equipment
Fixed Assets, net
Fixed assets, gross	225	228
Construction in progress
Fixed Assets, net
Fixed assets, gross	183	154
Other
Fixed Assets, net
Fixed assets, gross	$ 37	$ 45