CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (Unaudited) (Parenthetical) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Stock-based compensation expense	$ 15,100	$ 15,900	$ 29,700	$ 30,600
Depreciation expense			13,578	11,274
Cost of revenue
Stock-based compensation expense	1,386	2,199	3,281	3,448
Depreciation expense	2,634	2,537	5,168	4,909
Amortization of purchased intangibles	1,184	284	2,359	569
Sales and marketing
Stock-based compensation expense	3,373	2,525	7,155	7,664
Depreciation expense	615	620	1,218	1,287
General and administrative
Stock-based compensation expense	3,110	4,083	5,760	6,811
Depreciation expense	28	49	88	154
Product development
Stock-based compensation expense	7,218	7,138	13,502	12,719
Depreciation expense	$ 3,696	$ 2,532	$ 7,104	$ 4,924

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

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