Losses and Loss Adjustment Reserve - Effects of Reinsurance on Premiums Written and Earned (Detail) $ in Thousands	6 Months Ended
Jun. 30, 2019 USD ($)
Written
Direct premiums	$ 326,907
Ceded premiums	(326,901)
Net premiums	6
Earned
Direct premiums	321,233
Ceded premiums	(321,227)
Net premiums	$ 6

Amount of earned premiums ceded to other entities.

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Amount of written premiums ceded to other entities.

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