Summary of Significant Accounting Policies - Additional Information (Detail) (USD $)	12 Months Ended			12 Months Ended
	Dec. 31, 2012 Segment	Dec. 31, 2010	Dec. 31, 2011	Dec. 31, 2012 Non-compete agreements	Dec. 31, 2011 Non-compete agreements	Dec. 31, 2012 Minimum	Dec. 31, 2012 Minimum Non-compete agreements	Dec. 31, 2012 Maximum	Dec. 31, 2012 Maximum Non-compete agreements
Accounting Policies [Line Items]
Number of reportable segments	4
Number of units	2
Reserve for policy cancellations	$ 7,174,000		$ 6,396,000
Estimated useful lives of the related assets						3 years		15 years
Estimated lives of amortizable intangible assets				7 years 2 months 12 days	7 years 2 months 12 days		5 years		15 years
Outstanding options to purchase shares of common stock		12,000