Losses and Loss Adjustment Reserve - Effects of Reinsurance on Premiums Written and Earned (Detail) $ in Thousands	12 Months Ended
Dec. 31, 2015 USD ($)
Written
Direct premiums	$ 599,828
Assumed premiums	0
Ceded premiums	599,807
Net premiums	21
Earned
Direct premiums	610,753
Assumed premiums	18
Ceded premiums	610,750
Net premiums	$ 21

Amount of earned premiums assumed from other entities.

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