Net Loss per Share - Antidilutive Potential Common Shares (Details)		12 Months Ended
	Jul. 28, 2022	Dec. 31, 2023 shares	Dec. 31, 2022 shares	Dec. 31, 2021 shares
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive potential common stock (in shares)		13,576,961	11,824,869	6,909,558
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)		9,595,257	9,760,657	6,573,744
Unvested restricted stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive potential common stock (in shares)		3,568,735	1,651,243	335,814
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	0