Underwriting Information - Gross Written Premiums by Insurance Subsidiary (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Gross written premiums
Amount	$ 218,689	$ 129,359	$ 389,623	$ 232,936
% of GWP	100.00%	100.00%	100.00%	100.00%
PSIC
Gross written premiums
Amount	$ 116,338	$ 95,271	$ 220,342	$ 175,117
% of GWP	53.20%	73.60%	56.60%	75.20%
PESIC
Gross written premiums
Amount	$ 102,351	$ 34,088	$ 169,281	$ 57,819
% of GWP	46.80%	26.40%	43.40%	24.80%