Investment - Summary of Net Investment Income (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Schedule of Available-for-sale Securities [Line Items]
Net investment income	$ 996	$ 336	$ 1,799	$ 560
Investment expenses	277	212	462	225
Net investment income, less investment expenses	719	124	1,337	335
Fixed Maturities [Member]
Schedule of Available-for-sale Securities [Line Items]
Net investment income	633	207	1,152	366
Equity Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Net investment income	253	115	439	169
Cash and Cash Equivalents and Short-Term Investments [Member]
Schedule of Available-for-sale Securities [Line Items]
Net investment income	32	14	45	21
Other Investments [Member]
Schedule of Available-for-sale Securities [Line Items]
Net investment income	$ 78		$ 163	$ 4