Losses and Loss Adjustment Reserve - Effects of Reinsurance on Premiums Written and Earned (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014
Policyholders Account In Life Insurance Business [Abstract]
Written, Direct premiums	$ 439,828
Written, Assumed premiums	(1)
Written, Ceded premiums	439,819
Written, Net premiums	8
Earned, Direct premiums	408,056
Earned, Assumed premiums	199
Earned, Ceded premiums	408,247
Earned, Net premiums	$ 8