Reinsurance - Summary of Premiums Earned and Losses Incurred (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Premiums earned:
Direct	$ 279,613	$ 265,251
Assumed	872	121
Ceded	(30,724)	(33,265)
Net premiums earned	249,761	232,107
Losses incurred:
Direct	40,804	31,501
Assumed	(67)	90
Ceded	(1,674)	(7,741)
Losses incurred, net	$ 39,063	$ 23,850

Amount of earned premiums assumed from other entities.

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