Derivative Instruments and Hedging Activities (Details Textual) (USD $)	3 Months Ended			6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2009	Jun. 30, 2013	Jun. 30, 2012	Dec. 31, 2012
Interest Rate Caps Purchased			$ 7,100,000
Derivative Cap Fixed Interest Rate			2.97%
Deposits, Money Market Deposits	0		70,000,000	0
Future Interest Expenses on Hedge Terminated	1,300,000
Interest rate caps	0			0		14,000
Reduction in Money Market Deposits	68,000,000			0
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, before Tax	265,000	421,000		681,000	780,000
Interest Expense Hedged Deposits				695,000	962,000
Interest Expense Related To The Hedged Money Market Deposit Accounts Declined				267,000
Interest Expense Related To The Hedged Money Market Deposit Accounts Description				The interest expense associated with the hedged deposits will be $1.3 million less for 2013 than for 2012.
Interest Bearing Liabilities, Percentage				0.95%	1.20%
Accounts Payable, Interest-Bearing	$ 0			$ 0		$ 428,000