Investment Securities (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	9 Months Ended
	Mar. 31, 2012	Sep. 30, 2012	Sep. 30, 2011	Dec. 31, 2011
Securities Available for Sale:
Amortized Cost		$ 241,092		$ 300,998
Gross Unrealized Gains		1,734		3,408
Gross Unrealized Losses		(729)		(515)
Fair Value		242,097		303,891
Securities Held to Maturity:
Fair Value		46		46
Available-for-sale Amortized Cost [Abstract]
Due Less Than One Year		125
Due After One Year Through Five Years		2,697
Due After Five Years Through Ten Years		1,965
Due After Ten Years		575
Total		5,362
Mortgage-Backed Securities		235,730
Amortized Cost		241,092		300,998
Available-for-sale Fair Value [Abstract]
Due Less Than One Year		127
Due After One Year Through Five Years		2,847
Due After Five Years Through Ten Years		1,973
Due After Ten Years		340
Total		5,287
Mortgage-Backed Securities		236,810
Fair Value		242,097		303,891
Held-to-maturity Amortized Cost [Abstract]
Due Less Than One Year		0
Due After One Year Through Five Years		45
Due After Five Years Through Ten Years		0
Due After Ten Years		0
Total		45
Mortgage-Backed Securities		0
Amortized Cost		45
Held-to-maturity Fair Value [Abstract]
Due Less Than One Year		0
Due After One Year Through Five Years		46
Due After Five Years Through Ten Years		0
Due After Ten Years		0
Total		46
Mortgage-Backed Securities		0
Fair Value		46		46
Proceeds from sale of investment securities available for sale		161,811	251,044
Available-for-sale securities, gross realized gains		2,204	1,947
Available-for-sale securities, gross realized losses		(137)	(2)
Other than temporary impairment charges		(60)
Fair value of securities on nonaccrual status		132		132
Investment securities pledged		78,187		136,838
Continuous unrealized loss position [Abstract]
Less Than 12 Months, Fair value		68,596		27,664
12 Months or Greater, Fair value		2,367		1,195
Total, Fair Value		70,963		28,859
Less Than 12 Months, Gross Unrealized Losses		(465)		(209)
12 Months or Greater, Gross Unrealized Losses		(264)		(306)
Total, Unrealized Losses		(729)		(515)
Debt securities with unrealized losses, depreciated (in hundredths)		1.02%
Number of asset-backed security owned		1
Periods for asset-backed security in continuous unrealized loss position, minimum		12 months
Number of issuance of trust preferred security		1
Book value of trust preferred security		367
Unrealized loss on trust preferred security		235
Other than temporary impairment written off	60
US Government Agencies Mortgage-Backed [Member]
Securities Available for Sale:
Amortized Cost		235,730		291,097
Gross Unrealized Gains		1,573		3,152
Gross Unrealized Losses		(493)		(188)
Fair Value		236,810		294,061
Available-for-sale Amortized Cost [Abstract]
Amortized Cost		235,730		291,097
Available-for-sale Fair Value [Abstract]
Fair Value		236,810		294,061
Continuous unrealized loss position [Abstract]
Less Than 12 Months, Fair value		68,388		26,440
12 Months or Greater, Fair value		2,235		0
Total, Fair Value		70,623		26,440
Less Than 12 Months, Gross Unrealized Losses		(464)		(188)
12 Months or Greater, Gross Unrealized Losses		(29)		0
Total, Unrealized Losses		(493)		(188)
State, County & Municipal [Member]
Securities Available for Sale:
Amortized Cost		3,995		7,475
Gross Unrealized Gains		43		132
Gross Unrealized Losses		(1)		(23)
Fair Value		4,037		7,584
Securities Held to Maturity:
Amortized Cost		45		46
Gross Unrealized Gains		1		0
Gross Unrealized Losses		0		0
Fair Value		46		46
Available-for-sale Amortized Cost [Abstract]
Amortized Cost		3,995		7,475
Available-for-sale Fair Value [Abstract]
Fair Value		4,037		7,584
Held-to-maturity Fair Value [Abstract]
Fair Value		46		46
Continuous unrealized loss position [Abstract]
Less Than 12 Months, Fair value		208		1,224
12 Months or Greater, Fair value		0		73
Total, Fair Value		208		1,297
Less Than 12 Months, Gross Unrealized Losses		(1)		(21)
12 Months or Greater, Gross Unrealized Losses		0		(2)
Total, Unrealized Losses		(1)		(23)
Corporate Obligations [Member]
Securities Available for Sale:
Amortized Cost		1,000		2,000
Gross Unrealized Gains		118		124
Gross Unrealized Losses		0		(10)
Fair Value		1,118		2,114
Available-for-sale Amortized Cost [Abstract]
Amortized Cost		1,000		2,000
Available-for-sale Fair Value [Abstract]
Fair Value		1,118		2,114
Continuous unrealized loss position [Abstract]
Less Than 12 Months, Fair value				0
12 Months or Greater, Fair value				990
Total, Fair Value				990
Less Than 12 Months, Gross Unrealized Losses				0
12 Months or Greater, Gross Unrealized Losses				(10)
Total, Unrealized Losses				(10)
Asset-Backed Securities [Member]
Securities Available for Sale:
Amortized Cost		367		426
Gross Unrealized Gains		0		0
Gross Unrealized Losses		(235)		(294)
Fair Value		132		132
Available-for-sale Amortized Cost [Abstract]
Amortized Cost		367		426
Available-for-sale Fair Value [Abstract]
Fair Value		132		132
Continuous unrealized loss position [Abstract]
Less Than 12 Months, Fair value		0		0
12 Months or Greater, Fair value		132		132
Total, Fair Value		132		132
Less Than 12 Months, Gross Unrealized Losses		0		0
12 Months or Greater, Gross Unrealized Losses		(235)		(294)
Total, Unrealized Losses		$ (235)		$ (294)