Share-Based Awards (Tables)

12 Months Ended

Dec. 31, 2021

Share-based Payment Arrangement [Abstract]

Summary of Option Award Activity

The following table summarizes option award activity for the year ended December 31, 2021:

	Number of Shares Subject to Existing Options	Weighted- Average Exercise Price Per Share		Weighted- Average Remaining Contractual Life (Years)	Aggregate Intrinsic Value (in thousands)
Outstanding at January 1, 2021	20,051,051	$	42.68	7.22	$	1,751,105
Granted	10,290,760	121.71
Exercised	(3,304,241)	38.50
Forfeited or cancelled	(1,291,637)	81.37
Outstanding at December 31, 2021	25,745,933	72.86		7.48	354,479
Vested and exercisable at December 31, 2021	12,281,927	52.50		6.25	247,163

Fair Value of Options Granted, Estimated at Date of Grant Using Black Scholes Merton Option Pricing Model

The fair value of options granted is estimated at the date of grant using the Black-Scholes-Merton option-pricing model, assuming no dividends and with the following assumptions for the periods presented:

	Year Ended December 31,
	2021	2020	2019
Expected volatility	52% – 58%	45% – 52%	45% – 47%
Expected dividend yield	—	—	—
Risk-free interest rate	0.57% – 1.15%	0.22% – 0.93%	1.60% – 2.53%
Weighted-average expected life	4.50 – 5.75 years	4.50 – 5.50 years	4.75 – 5.25 years
Weighted-average fair value of options granted	$54.55	$22.50	$16.52

Summary of Restricted Stock Units Activity

The following table summarizes activity for restricted stock units for the year ended December 31, 2021:

	Restricted Stock Units	Weighted- Average Grant- Date Fair Value
Unvested outstanding at January 1, 2021	7,316,557	$	48.14
Granted	2,744,325	96.48
Vested	(2,982,148)	51.02
Forfeited	(1,004,635)	60.59
Unvested outstanding at December 31, 2021	6,074,099	66.51

Effects of Share Based Compensation in Consolidated Statements of Operations

The following table presents the effects of share-based compensation expense in our consolidated statements of operations during the periods presented (in thousands):

	Year Ended December 31,
	2021		2020		2019
Cost of revenue	$	10,968	$	6,685	$	4,972
Sales and marketing	48,131		33,110		25,126
Technology and development	117,614		80,876		68,927
General and administrative	134,973		76,879		99,877
Impairment and restructuring costs	5,506		—		—
Total	$	317,192	$	197,550	$	198,902