Debentures Payable (Details Textual) (USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended			12 Months Ended
	Apr. 30, 2013	Jan. 31, 2013	Oct. 31, 2012	Dec. 31, 2012	Dec. 31, 2012 Junior Subordinated Debentures [Member]	Jul. 30, 2012 Junior Subordinated Debentures [Member]
Debentures Payable (Textual) [Abstract]
Debentures paid fixed rate						9.277%
Variable rate					Three-Month LIBOR plus 375 basis points
Variable rate basis point					3.75%
Debentures Payable (Additional Textual) [Abstract]
Preferred stock shares issued by unconsolidated trust				40,000
Common stock shares issued by unconsolidated trust				1,240
Price of preferred and common shares issued by unconsolidated trust				$ 1,000
Proceeds to unconsolidated trust from issuance of junior subordinated debenture sale of preferred stock shares				$ 41.2
Maturity date				Jul. 30, 2037
Interest rate	4.052%	4.063%	4.197%
Period for deferral of preferred securities dividend				5 years
Unamortized debt discount				1.0
Unamortized issuance costs				$ 1.0