CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (Unaudited) (Parenthetical) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Stock-based compensation expense	$ 18,300	$ 15,500	$ 48,000	$ 46,200
Depreciation expense			20,471	17,223
Cost of revenue
Stock-based compensation expense	1,337	2,288	4,618	5,735
Depreciation expense	2,552	2,710	7,720	7,619
Amortization of purchased intangibles	1,343	286	3,702	854
Sales and marketing
Stock-based compensation expense	4,228	1,873	11,383	9,536
Depreciation expense	602	511	1,820	1,798
General and administrative
Stock-based compensation expense	4,103	3,618	9,863	10,428
Depreciation expense	15	53	103	207
Product development
Stock-based compensation expense	8,601	7,753	22,103	20,472
Depreciation expense	$ 3,724	$ 2,674	$ 10,828	$ 7,599

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

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