Investments - Progression of Credit-Related Portion of OTTI on Investments (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
Investments Debt And Equity Securities [Abstract]
Beginning balance	$ (3,343)	$ (2,666)	$ (3,425)	$ (3,301)
Additional credit impairments on:
Previously impaired securities	(127)	(61)	(23)	(413)
Securities without previous impairments
Total additional credit impairments securities	(127)	(61)	(23)	(413)
Reductions for securities sold (realized)	45	95	782	371
Ending balance	$ (3,425)	$ (2,632)	$ (2,666)	$ (3,343)