Stock-based Compensation (Tables)

9 Months Ended

12 Months Ended

Sep. 30, 2020

Dec. 31, 2019

Stock-based Compensation

Fair value assumptions

The fair value of each option granted for the nine months ended September 30, 2020 and 2019 is estimated on the date of grant using the Black-Scholes model based on the following assumptions:

	Nine Months Ended
	September 30,
	2020		2019
Weighted average expected term (years)	6.1		6.1
Risk-free interest rate	0.8	%	1.7	%
Volatility	40	%	45	%
Expected dividend yield	0	%	0	%

The fair value of each option granted during the year ended December 31, 2018 and 2019 is estimated on the date of grant using the Black-Scholes model with the following assumptions (annualized percentage):

	December 31,
	2018		2019
Weighted average expected term (years)	6.07		6.06
Risk‑free interest rate	2.6% ‑ 3.1	%	1.3% ‑ 2.5	%
Volatility	50	%	45	%
Expected dividend yield	0	%	0	%

Stock options activity

The following table summarizes activity of stock options ($ in millions, except for option and average amounts):

				Weighted-
		Weighted-		Average
		Average		Remaining	Aggregate
	Number of	Exercise		Contractual	Intrinsic
	Options	Price		Term (Years)	Value
Outstanding as of December 31, 2019	4,048,802	$	13.27	8.8	$	42.2
Granted	968,280		30.44
Exercised	(92,157)		3.77
Cancelled	(110,001)		20.87
Outstanding as of September 30, 2020	4,814,924	$	16.73	8.4	$	158.8
Options exercisable as of September 30, 2020	1,698,568	$	8.72	7.5	$	69.6
Options vested and expected to vest as of September 30, 2020	4,814,924	$	16.73	8.4	$	158.8

The following table summarizes activity under the 2015 Plan of stock options granted ($ in millions, except for option and average amounts):

				Weighted‑
				Average
		Weighted‑		Remaining
		Average		Contractual	Aggregate
	Number of	Exercise		Term	Intrinsic
	Options	Price		(Years)	Value
Outstanding as of December 31, 2018	2,169,000	$	3.62	8.75	$	17.3
Granted	2,255,800		21.17	9.40
Exercised	(182,057)		1.73
Cancelled	(193,941)		7.99
Outstanding as of December 31, 2019	4,048,802	$	13.27	8.83	$	42.2
Options exercisable as of December 31, 2019	987,985	$	4.00	7.52	$	19.5
Options unvested as of December 31, 2019	3,110,817	$	16.39	9.25	$	22.7

Stock-based compensation expense

Stock-based compensation expense was classified in the condensed consolidated statements of operations as follows ($ in millions):

	Three Months Ended				Nine Months Ended
	September 30,				September 30,
	2020		2019		2020		2019
Loss and loss adjustment expense, net	$	0.1	$	—	$	0.2	$	—
Other insurance expense		0.1		0.2		0.5		0.4
Sales and marketing		0.8		0.3		2.1		0.5
Technology development		0.8		0.7		2.1		0.8
General and administrative		0.9		0.3		2.4		0.6
Total stock-based compensation expense	$	2.7	$	1.5	$	7.3	$	2.3

Stock-based compensation expense was classified in the consolidated statements of operations and comprehensive loss as follows ($ in millions):

	Year Ended
	December 31,
	2018		2019
Other insurance expense	$	0.2	$	0.6
Sales and marketing		0.3		1.1
Technology development		0.1		1.4
General and administrative		1.5		1.2
Total stock‑based compensation expense	$	2.1	$	4.3