Investment Securities - Schedule of Investments in Accordance with Fair Value Measurement (Detail) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Class of securities:
Total fixed-maturity securities, Estimated Fair Value	$ 88,039	$ 99,055
Total investments fair value	94,173	106,356
Money Market Funds [Member]
Class of securities:
Money market funds	6,134	7,301
Level 1
Class of securities:
Total fixed-maturity securities, Estimated Fair Value	66,344	75,037
Total investments fair value	72,478	82,338
Level 1 | Money Market Funds [Member]
Class of securities:
Money market funds	6,134	7,301
Level 2
Class of securities:
Total fixed-maturity securities, Estimated Fair Value	21,695	24,018
Total investments fair value	21,695	24,018
U.S. Government Treasury Securities [Member]
Class of securities:
Total fixed-maturity securities, Estimated Fair Value	250	248
U.S. Government Treasury Securities [Member] | Level 1
Class of securities:
Total fixed-maturity securities, Estimated Fair Value	250	248
Obligations of U.S. Government Sponsored Enterprises [Member]
Class of securities:
Total fixed-maturity securities, Estimated Fair Value	60,481	69,382
Obligations of U.S. Government Sponsored Enterprises [Member] | Level 1
Class of securities:
Total fixed-maturity securities, Estimated Fair Value	55,979	63,909
Obligations of U.S. Government Sponsored Enterprises [Member] | Level 2
Class of securities:
Total fixed-maturity securities, Estimated Fair Value	4,502	5,473
Corporate Debt Securities [Member]
Class of securities:
Total fixed-maturity securities, Estimated Fair Value	18,930	21,061
Corporate Debt Securities [Member] | Level 1
Class of securities:
Total fixed-maturity securities, Estimated Fair Value	7,608	8,873
Corporate Debt Securities [Member] | Level 2
Class of securities:
Total fixed-maturity securities, Estimated Fair Value	11,322	12,188
Foreign Corporate Debt Securities [Member]
Class of securities:
Total fixed-maturity securities, Estimated Fair Value	8,378	8,364
Foreign Corporate Debt Securities [Member] | Level 1
Class of securities:
Total fixed-maturity securities, Estimated Fair Value	2,507	2,007
Foreign Corporate Debt Securities [Member] | Level 2
Class of securities:
Total fixed-maturity securities, Estimated Fair Value	$ 5,871	$ 6,357