Derivative Instruments and Hedging Activities (Details Textual) (USD $)	3 Months Ended			9 Months Ended		12 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Jun. 30, 2009	Sep. 30, 2013	Sep. 30, 2012	Dec. 31, 2012
Interest Rate Caps Purchased			$ 7,100,000
Derivative Cap Fixed Interest Rate			2.97%
Deposits, Money Market Deposits			70,000,000
Future Interest Expenses on Hedge Terminated				1,300,000
Interest rate caps	0			0		14,000
Reduction in Money Market Deposits				204,300,000		279,000,000
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, before Tax	0	479,000		681,000	1,259,000
Interest Expense Hedged Deposits				695,000	1,500,000
Accounts Payable, Interest-Bearing	$ 0			$ 0		$ 428,000