Common Stock and Stockholders' Equity - Compensation Costs (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Compensation costs charged as an expense
Stock-based compensation	$ 86,300	$ 18,315
Cost of revenue (exclusive of depreciation and amortization, which is shown separately)
Compensation costs charged as an expense
Stock-based compensation	2,362	0
Advertising and marketing
Compensation costs charged as an expense
Stock-based compensation	5,082	1,259
Sales
Compensation costs charged as an expense
Stock-based compensation	21,167	2,919
Technology and development
Compensation costs charged as an expense
Stock-based compensation	26,726	2,104
General and administrative expenses
Compensation costs charged as an expense
Stock-based compensation	$ 30,963	$ 12,033