Reinsurance - Summary of Premiums Earned and Losses Incurred (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Premiums earned:
Direct	$ 305,921	$ 287,183	$ 595,789	$ 566,796
Assumed	3,381	1,015	5,990	1,887
Ceded (1)	(65,740)	(41,096)	(97,316)	(71,820)
Net premiums earned	243,562	247,102	504,463	496,863
Losses incurred:
Direct	256,224	25,276	322,786	66,080
Assumed	133	(9)	299	(76)
Ceded	(38,983)	(3,431)	(44,755)	(5,105)
Losses incurred, net	$ 217,374	$ 21,836	$ 278,330	$ 60,899

Amount of earned premiums assumed from other entities.

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