On-Balance Sheet Derivative Instruments And Hedging Activities (Narrative) (Details) (USD $)	6 Months Ended		12 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Dec. 31, 2010
Fair value of derivatives	95,000
Interest rate swaps, interest expense decreased	856,000	811,000
Derivative, Collateral, Right to Reclaim Cash	1,210,000
Derivative Instruments On Debt [Member]
Derivative, notional amount	70,000,000	95,000,000
Customer Interest Rate Contracts [Member]
Derivative, notional amount	274,688,000
Offsetting Interest Rate Contracts [Member]
Derivative, notional amount	274,688,000	201,327,000	247,292,000
Equity Indexed Certificates Of Deposit Asset [Member]
Derivative, notional amount	123,880,000	11,399,000
Equity Indexed Certificates of Deposit Liability [Member]
Derivative, notional amount	123,880,000	11,399,000