Unpaid Loss and Loss Adjustment Expense - Claims Development Information, Incurred Losses (Details)	Dec. 31, 2021 USD ($) claim	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Home
Claims Development [Line Items]
Total incurred losses and ALAE, net	$ 172,500,000
IBNR	$ 12,200,000
Cumulative Number of Reported Claims | claim	112,810
Pet
Claims Development [Line Items]
Total incurred losses and ALAE, net	$ 10,200,000
IBNR	$ 2,100,000
Cumulative Number of Reported Claims | claim	193,794,000,000
2016 | Home
Claims Development [Line Items]
Total incurred losses and ALAE, net	$ 0	$ 0	$ 0	$ 0	$ 0	$ 0
IBNR	$ 0
Cumulative Number of Reported Claims | claim	8
2017 | Home
Claims Development [Line Items]
Total incurred losses and ALAE, net	$ 1,700,000	1,700,000	1,700,000	1,700,000	$ 1,700,000
IBNR	$ 0
Cumulative Number of Reported Claims | claim	1,758
2018 | Home
Claims Development [Line Items]
Total incurred losses and ALAE, net	$ 13,400,000	13,400,000	13,500,000	$ 15,000,000.0
IBNR	$ 0
Cumulative Number of Reported Claims | claim	10,528
2019 | Home
Claims Development [Line Items]
Total incurred losses and ALAE, net	$ 46,200,000	46,000,000.0	$ 46,000,000.0
IBNR	$ 0
Cumulative Number of Reported Claims | claim	19,483
2020 | Home
Claims Development [Line Items]
Total incurred losses and ALAE, net	$ 51,800,000	53,200,000
IBNR	$ 1,100,000
Cumulative Number of Reported Claims | claim	30,212
2020 | Pet
Claims Development [Line Items]
Total incurred losses and ALAE, net	$ 200,000	$ 300,000
IBNR	$ 0
Cumulative Number of Reported Claims | claim	20,415,000,000
2021
Claims Development [Line Items]
Total incurred losses and ALAE, net	$ 69,400,000
2021 | Home
Claims Development [Line Items]
Total incurred losses and ALAE, net	59,400,000
IBNR	$ 11,100,000
Cumulative Number of Reported Claims | claim	50,821
2021 | Pet
Claims Development [Line Items]
Total incurred losses and ALAE, net	$ 10,000,000.0
IBNR	$ 2,100,000
Cumulative Number of Reported Claims | claim	173,379,000,000