Reinsurance - Summary of Premiums Earned and Losses Incurred (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Premiums earned:
Direct	$ 293,047	$ 305,921	$ 589,318	$ 595,789
Assumed	2,480	3,381	4,891	5,990
Ceded	(43,988)	(65,740)	(87,625)	(97,316)
Net premiums earned	251,539	243,562	506,584	504,463
Losses incurred:
Direct	37,983	256,224	86,054	322,786
Assumed	79	133	54	299
Ceded	(8,898)	(38,983)	(17,308)	(44,755)
Losses incurred, net	$ 29,164	$ 217,374	$ 68,800	$ 278,330

Amount of earned premiums assumed from other entities.

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