Investments - Amortized Cost and Fair Value of Fixed Maturity Securities by Contractual Maturity (Detail) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Amortized Cost
Due in one year or less	$ 9,034	$ 5,628
Due after one year through five years	13,466	13,863
Due after five years through ten years	330	330
Amortized Cost, Total	22,830	19,821
Fair Value
Due in one year or less	9,039	5,628
Due after one year through five years	13,569	13,897
Due after five years through ten years	335	337
Fair Value, Total	$ 22,943	$ 19,862