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		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Costs and expenses:
Amortization adjustment	$ 17	$ 18	$ 52	$ 54
Stock-based compensation:
Stock-based compensation	28	29	80	91
Selling and Marketing
Stock-based compensation:
Stock-based compensation	4	5	12	17
Technology and Content
Stock-based compensation:
Stock-based compensation	12	13	32	40
General and Administrative
Stock-based compensation:
Stock-based compensation	12	11	35	33
Cost of Revenue
Stock-based compensation:
Stock-based compensation			1	1
Acquired Technology
Costs and expenses:
Amortization of intangible assets	1	3	2	7
Website Development Costs
Costs and expenses:
Depreciation	$ 16	$ 15	$ 50	$ 47