Premiums Receivable - Summarizes the Activity in the Allowance for Doubtful Accounts (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Premiums Receivable, Allowance for Doubtful Accounts [Roll Forward]
Balance, beginning of year	$ 6,424	$ 5,573	$ 5,104
Provision for bad debts	52	2,230	1,209
Write-offs	(1,018)	(1,379)	(740)
Balance, end of year	$ 5,458	$ 6,424	$ 5,573