Borrowings - Additional Information (Detail) (USD $)	9 Months Ended		9 Months Ended		1 Months Ended		12 Months Ended			9 Months Ended
	Sep. 30, 2013	Sep. 30, 2013 Maximum [Member]	Sep. 30, 2013 Subordinated Debentures 2033 [Member]	Sep. 30, 2013 Subordinated Debentures 2034 [Member]	May 31, 2004 Subordinated Debentures [Member]	Oct. 31, 2003 Subordinated Debentures [Member]	Dec. 31, 2010 Subordinated Debentures [Member]	Sep. 30, 2013 Subordinated Debentures [Member]	Sep. 30, 2013 Subordinated Debentures [Member] Three-month LIBOR rate plus 3.85% [Member]	Sep. 30, 2013 Lines of Credit [Member]	Mar. 31, 2013 Atlantic States [Member]	Dec. 31, 2012 Atlantic States [Member] Pittsburgh [Member]	Mar. 31, 2013 Atlantic States [Member] Lines of Credit [Member]	Sep. 30, 2013 West Bend Mutual Insurance Company [Member] Subordinated Debentures [Member]	Sep. 30, 2013 MICO [Member] Indianapolis [Member]	Dec. 31, 2012 MICO [Member] Indianapolis [Member]	Sep. 30, 2013 MICO [Member] Lines of Credit [Member] Indianapolis [Member]	Jun. 30, 2013 Manufacturers and Traders Trust Company [Member] Lines of Credit [Member]
Line of Credit Facility [Line Items]
Right to request for extension of credit agreement with Manufacturers and Traders Trust Company																	$ 2,514,048	$ 60,000,000
Line of credit that expires date										2016-07
Outstanding borrowings										49,500,000
Line of credit facility remaining borrowing capacity										10,500,000
Line of credit, interest rate related to Libor rate description										Interest rates equal to M&T's current prime rate or the then current LIBOR rate plus 2.25%
Debt instrument interest rate effective percentage		2.25%						3.85%	3.85%
Interest rate on borrowings										2.43%
Percentage commitment fee	0.20%
Revolving credit facility, borrowing interest rate	The credit agreement requires our compliance with certain covenants. These covenants include minimum levels of our net worth, leverage ratio, statutory surplus and the A.M. Best ratings of our insurance subsidiaries. We complied with all requirements of the credit agreement during the nine months ended September 30, 2013.
Federal home loan bank borrowing amount outstanding												0			0	0
Interest rate on advances													0.24%
Debt issued to FHLB in exchange of advance cash											15,000,000
Debt instrument, description	On October 29, 2003, we received $10.0 million in net proceeds from the issuance of subordinated debentures. The debentures had a maturity date of October 29, 2033 and were callable at our option, at par. The debentures carried an interest rate equal to the three-month LIBOR rate plus 3.85%.
Debentures, interest rate related to Libor rate description	Interest rate equal to the three-month LIBOR rate plus 3.85%
Revolving line of credit expiration date	Oct. 29, 2033
Net proceeds from the issuance of subordinated debentures					5,000,000	10,000,000
Payment date of subordinated debentures and liquidated investment in the statutory trust			Jan. 28, 2013	Feb. 25, 2013
Debentures maturity date	May 24, 2034
Debt Instrument basis spread on variable rate							5.00%
Purchase of surplus note														$ 5,000,000