Losses and Loss Adjustment Reserve - Effects of Reinsurance on Premiums Written and Earned (Detail) $ in Thousands	6 Months Ended
Jun. 30, 2015 USD ($)
Written
Direct premiums	$ 288,055
Assumed premiums	0
Ceded premiums	288,049
Net premiums	6
Earned
Direct premiums	306,045
Assumed premiums	18
Ceded premiums	306,057
Net premiums	$ 6

Amount of earned premiums assumed from other entities.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 235
-Section S99
-Paragraph 2
-Subparagraph (SX 210.12-17)
-URI http://asc.fasb.org/extlink&oid=34713774&loc=d3e574992-122915

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