The aggregate amount of recurring noncash expense charged against earnings in the period to allocate the cost of assets over their estimated remaining economic lives.

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Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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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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Condensed Consolidated Statements of Operations (Parenthetical) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Costs and expenses:
Amortization adjustment	$ 18	$ 17	$ 35	$ 36
Stock-based compensation:
Stock-based compensation	25	32	51	60
Selling and Marketing
Stock-based compensation:
Stock-based compensation	4	6	7	11
Technology and Content
Stock-based compensation:
Stock-based compensation	9	14	20	27
General and Administrative
Stock-based compensation:
Stock-based compensation	12	12	23	22
Cost of Revenue
Stock-based compensation:
Stock-based compensation			1
Acquired Technology
Costs and expenses:
Amortization of intangible assets	1	2	1	4
Website Development Costs
Costs and expenses:
Depreciation	$ 17	$ 15	$ 34	$ 32