Investment Securities - Schedule of Amortized Cost, Gross Unrealized Gains, Gross Unrealized Losses and Estimated Fair Values of Fixed-Maturity Securities (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Schedule of Trading Securities and Other Trading Assets [Line Items]
Total fixed-maturity securities, Amortized Cost	$ 99,088	$ 60,202
Total fixed-maturity securities, Gross Unrealized Gains	78	590
Total fixed-maturity securities, Gross Unrealized Losses	(111)	(151)
Total fixed-maturity securities, Estimated Fair Value	99,055	60,641
Unrestricted Fixed-Maturity Securities [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Total fixed-maturity securities, Amortized Cost	66,481	7,895
Total fixed-maturity securities, Gross Unrealized Gains	14	179
Total fixed-maturity securities, Gross Unrealized Losses	(11)	(11)
Total fixed-maturity securities, Estimated Fair Value	66,484	8,063
Fixed-Maturity Securities Held in Trust [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Total fixed-maturity securities, Amortized Cost	32,607	52,307
Total fixed-maturity securities, Gross Unrealized Gains	64	411
Total fixed-maturity securities, Gross Unrealized Losses	(100)	(140)
Total fixed-maturity securities, Estimated Fair Value	32,571	52,578
U.S. Government Treasury Securities [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Total fixed-maturity securities, Amortized Cost	249
Total fixed-maturity securities, Gross Unrealized Losses	(1)
Total fixed-maturity securities, Estimated Fair Value	248
Obligations of U.S. Government Sponsored Enterprises [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Total fixed-maturity securities, Amortized Cost	69,392	6,491
Total fixed-maturity securities, Gross Unrealized Gains	13	12
Total fixed-maturity securities, Gross Unrealized Losses	(23)	(28)
Total fixed-maturity securities, Estimated Fair Value	69,382	6,475
Corporate Debt Securities [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Total fixed-maturity securities, Amortized Cost	21,048	41,018
Total fixed-maturity securities, Gross Unrealized Gains	62	531
Total fixed-maturity securities, Gross Unrealized Losses	(49)	(65)
Total fixed-maturity securities, Estimated Fair Value	21,061	41,484
Foreign Corporate Debt Securities [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Total fixed-maturity securities, Amortized Cost	8,399	12,693
Total fixed-maturity securities, Gross Unrealized Gains	3	47
Total fixed-maturity securities, Gross Unrealized Losses	(38)	(58)
Total fixed-maturity securities, Estimated Fair Value	$ 8,364	$ 12,682