Net Loss per Share - Antidilutive Potential Common Shares (Details)		9 Months Ended
	Jul. 28, 2022	Sep. 30, 2024 shares	Sep. 30, 2023 shares
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive potential common stock (in shares)		15,083,442	13,475,220
Metromile
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Conversion ratio	0.05263
Options to purchase common stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive potential common stock (in shares)		10,347,561	9,722,479
Unvested restricted stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive potential common stock (in shares)		4,322,912	3,339,772
Warrants for common stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive potential common stock (in shares)		412,969	412,969