Equity and Equity Compensation Plans (Tables)

9 Months Ended

Sep. 30, 2020

Share-based Payment Arrangement [Abstract]

Schedule of Reserved Shares of Common Stock

We have reserved shares of common stock for future issuance under our 2017 EIP as follows:

	September 30, 2020	December 31, 2019
Stock options issued and outstanding	5,924,213	7,792,181
Restricted stock units issued and outstanding or deferred	3,948,967	5,023,412
Shares available for future equity grants	12,155,042	7,100,499
Total shares reserved for future issuance	22,028,222	19,916,092

We have reserved shares of common stock for future issuance under our ESPP as follows:

	Nine Months Ended September 30, 2020	Year Ended December 31, 2019
Shares available for issuance at beginning of period	3,330,271	2,890,973
Shares issued during the period	186,925	490,717
Total shares available for future issuance at end of period	3,143,346	2,400,256

Schedule of Stock Option Activity

The following table summarizes activity for stock options for the nine months ended September 30, 2020:

	Number of Options	Weighted- Average Exercise Price		Weighted-Average Remaining Contractual Life (Years)	Aggregate Intrinsic Value
Outstanding as of January 1, 2020	7,792,181	$	7.00	5.28	$	111,122
Options exercised	(1,825,684)	6.30
Options forfeited	(31,990)	8.92
Options expired	(10,294)	8.98
Outstanding at September 30, 2020	5,924,213	7.20		4.66	253,117
Options exercisable at September 30, 2020	5,635,344	6.59		4.51	244,262

Schedule of Nonvested Restricted Stock Units Activity

The following table summarizes activity for restricted stock units for the nine months ended September 30, 2020:

	Restricted Stock Units	Weighted Average Grant-Date Fair Value
Outstanding as of January 1, 2020	5,023,412	$	18.69
Granted	617,728	30.72
Vested(1)	(1,017,675)	18.98
Forfeited or canceled	(674,498)	19.22
Outstanding or deferred as of September 30, 2020(1)	3,948,967	$	20.40

(1) Starting with the restricted stock units granted to them in June 2019, our non-employee directors have the option to defer the issuance of common stock receivable upon vesting of such restricted stock units until 60 days following the day they are no longer providing services to us or, if earlier, upon a change in control transaction. The amount reported as vested excludes restricted stock units that have vested but whose settlement into shares have been deferred. The amount reported as outstanding or deferred as of September 30, 2020 includes these restricted stock units. As no further conditions exist to prevent the issuance of the shares of common stock underlying these restricted stock units, the shares are included in basic and diluted weighted shares outstanding used to calculate net loss per share attributable to common stock. The amount of shares whose issuance have been deferred is not considered material and is not reported separately from stock-based compensation in our consolidated statements of changes in mezzanine equity and stockholders’ equity.

Schedule of Allocation of Share-based Compensation Costs

The following table details, for each period indicated, (i) our stock-based compensation, net of forfeitures, and the amount capitalized in internally developed software and (ii) changes to the probability of achieving outstanding performance-based equity awards, each as included in our consolidated statements of comprehensive income (loss):

	Three Months Ended September 30,				Nine Months Ended September 30,
	2020		2019		2020		2019
Cost of revenue	$	2,574	$	1,605	$	5,981	$	4,398
Technology and development	4,964		3,320		11,736		8,661
Marketing	403		390		1,130		1,025
General and administrative	3,407		2,195		6,917		5,708
Total stock-based compensation	$	11,348	$	7,510	$	25,764	$	19,792