Securities (Details Textual) (USD $)	9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Dec. 31, 2011
Securities (Textual) [Abstract]
Total Temporarily Impaired Securities Continuous Unrealized Loss Position Unrealized Losses	$ 1,312,000		$ 3,976,000
Securities (Additional Textual) [Abstract]
Proceeds from sale of securities	248,509,000	33,555,000
Gains from sale of securities	7,037,000	153,000
Gross losses	0	16,000
Maturity of securities available for sale	95,658,000	87,713,000
Securities with Carrying Value and Fair Value Pledged as Collateral for Repurchase Agreement	143,741,000
Federal Home Loan Bank and Federal Reserve Bank stock	11,700,000
Fair value of cost method investment securities	11,700,000
Collateral Underlying Mortgage Investments Terms	30- and 15-year fixed and 10/1 adjustable rate mortgages
Private collateralized mortgage obligations [Member]
Securities (Textual) [Abstract]
Aggregate Losses	(84,000)		(3,487,000)
Total Temporarily Impaired Securities Continuous Unrealized Loss Position Unrealized Losses	1,300,000
Fair Value, Total	10,106,000		59,897,000
Mortgage-backed securities of U.S Government Sponsored Entities [Member]
Securities (Textual) [Abstract]
Aggregate Losses	(86,000)		(37,000)
Fair Value, Total	23,096,000		18,800,000
Mortgage Backed Securities And Collateralized Mortgage Obligations Of US Government Sponsored Entities [Member]
Securities (Textual) [Abstract]
Aggregate Losses	1,200,000
Fair Value, Total	178,900,000
Available for Sale Securities Pledged as Collateral Carrying Value [Member]
Securities (Textual) [Abstract]
Securities pledged as collateral	72,018,000
Fair Value [Member]
Securities (Textual) [Abstract]
Securities pledged as collateral	$ 73,173,000