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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Property and Equipment (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
Property and Equipment (Detail) - USD ($) $ in Millions	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 1,506		$ 1,506		$ 1,292
Less: Accumulated depreciation	(766)		(766)		(632)
Property and equipment, net	740		740		660
Depreciation	83	$ 58	232	$ 160
Computer equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	1,154		1,154		974
Computer software
Property, Plant and Equipment [Line Items]
Property and equipment, gross	77		77		72
Leasehold and other improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	184		184		168
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property and equipment, gross	70		70		69
Construction in progress
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 21		$ 21		$ 9