Troubled Debt Restructurings (Details Textual) (USD $) In Millions, unless otherwise specified	9 Months Ended
	Sep. 30, 2012 Investment	Dec. 31, 2011 Investment
Troubled Debt Restructurings (Textual)
Total number of loans classified under troubled debt restructurings (TDRs)	39	42
Total sum of loans classified as troubled debt restructurings (TDRs)	$ 14.0	$ 12.2
Number of days after loans subsequently defaulted	More than 60 days