Derivatives and Hedging Activities (Details Textual) (USD $)	12 Months Ended				12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2011 Government Agency Issued Bonds or MBS [Member]	Dec. 31, 2010 Government Agency Issued Bonds or MBS [Member]	Dec. 31, 2009 Designated as Hedging Instrument [Member] Interest Rate Swap [Member]
Derivative [Line Items]
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net					$ 700,000
Derivative Instruments, Gain (Loss) Recognized in Income, Ineffective Portion and Amount Excluded from Effectiveness Testing, Net					300,000
Collateral Already Posted, Aggregate Fair Value			107,000,000	85,200,000
Term of written loan commitments, days	60
Default Assumptions Percentage	100.00%
Maximum value of the guaranteed derivative instruments	3,100,000
Collateral posted against derivative liabilities			$ 107,000,000	$ 85,200,000
TBA Securities Outstanding at Year End	0	0
Remaining Term on Swap Participation Agreements, Min	1 year
Remaining Term on Swap Participation Agreements, Max	7 years