Investments - Major Categories of Investment Income (Detail) (USD $) In Thousands, unless otherwise specified	6 Months Ended	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2013	Dec. 31, 2012	Jun. 30, 2011
Net Investment Income [Line Items]
Investment expenses	$ (316)	$ (576)	$ (619)	$ (651)
Investment income	3,930	5,716	6,599	8,395
Fixed Maturities, Available-for-Sale [Member]
Net Investment Income [Line Items]
Investment income	3,897	5,037	6,513	8,296
Mutual Fund, Available-for-Sale [Member]
Net Investment Income [Line Items]
Investment income	290	766	613	625
Limited Partnership Interests [Member]
Net Investment Income [Line Items]
Investment income		200
Equity in Earnings of Limited Partnership Interest [Member]
Net Investment Income [Line Items]
Investment income		199
Other [Member]
Net Investment Income [Line Items]
Investment income	$ 59	$ 90	$ 92	$ 125