Investment Securities (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013 Security	Mar. 31, 2012	Dec. 31, 2012
Securities Available for Sale [Abstract]
Amortized Cost	$ 289,823		$ 268,527
Gross Unrealized Gains	613		974
Gross Unrealized Losses	(2,187)		(1,200)
Fair Value	288,249		268,301
Securities Held to Maturity [Abstract]
Amortized Cost	43		41
Gross Unrealized Gains	0		1
Gross Unrealized Losses	0		0
Fair Value	43		42
Available-for-sale Amortized Cost [Abstract]
Due After One Year Through Five Years	2,754
Due After Five Years Through Ten Years	1,765
Due After Ten Years	1,021
Total	5,540
Mortgage-Backed Securities	284,283
Amortized Cost	289,823
Available-for-sale Fair Value [Abstract]
Due After One Year Through Five Years	2,882
Due After Five Years Through Ten Years	1,779
Due After Ten Years	778
Total	5,439
Mortgage-Backed Securities	282,810
Fair Value	288,249
Held-to-maturity Amortized Cost [Abstract]
Due After One Year Through Five Years	43
Due After Five Years Through Ten Years	0
Due After Ten Years	0
Total	43
Mortgage-Backed Securities	0
Amortized Cost	43
Held-to-maturity Fair Value [Abstract]
Due After One Year Through Five Years	43
Due After Five Years Through Ten Years	0
Due After Ten Years	0
Total	43
Mortgage-Backed Securities	0
Fair Value	43
Proceeds from sale of investment securities available for sale	30,418	6,082
Available-for-sale securities, gross realized gains	125	197
Available-for-sale securities, gross realized losses	(133)
Other than temporary impairment charges		(60)
Fair value of securities on nonaccrual status	132		132
Investment securities pledged	118,473		117,451
Continuous unrealized loss position [Abstract]
Less Than 12 Months, Fair value	201,067		143,535
12 Months or Greater, Fair value	132		132
Total, Fair Value	201,199		143,667
Less Than 12 Months, Gross Unrealized Losses	(1,952)		(966)
12 Months or Greater, Gross Unrealized Losses	(235)		(234)
Total, Unrealized Losses	(2,187)		(1,200)
Debt securities with unrealized losses, depreciated (in hundredths)	1.07%
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
US Government Agencies Mortgage-Backed [Member]
Securities Available for Sale [Abstract]
Amortized Cost	284,283		263,187
Gross Unrealized Gains	471		835
Gross Unrealized Losses	(1,944)		(962)
Fair Value	282,810		263,060
Continuous unrealized loss position [Abstract]
Less Than 12 Months, Fair value	200,421		142,104
12 Months or Greater, Fair value	0		0
Total, Fair Value	200,421		142,104
Less Than 12 Months, Gross Unrealized Losses	(1,944)		(962)
12 Months or Greater, Gross Unrealized Losses	0		0
Total, Unrealized Losses	(1,944)		(962)
State, County & Municipal [Member]
Securities Available for Sale [Abstract]
Amortized Cost	4,173		3,974
Gross Unrealized Gains	44		34
Gross Unrealized Losses	(8)		(4)
Fair Value	4,209		4,004
Continuous unrealized loss position [Abstract]
Less Than 12 Months, Fair value	646		1,431
12 Months or Greater, Fair value	0		0
Total, Fair Value	646		1,431
Less Than 12 Months, Gross Unrealized Losses	(8)		(4)
12 Months or Greater, Gross Unrealized Losses	0		0
Total, Unrealized Losses	(8)		(4)
Corporate Obligations [Member]
Securities Available for Sale [Abstract]
Amortized Cost	1,000		1,000
Gross Unrealized Gains	98		105
Gross Unrealized Losses	0		0
Fair Value	1,098		1,105
Asset-Backed Securities [Member]
Securities Available for Sale [Abstract]
Amortized Cost	367		366
Gross Unrealized Gains	0		0
Gross Unrealized Losses	(235)		(234)
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)		(234)
Total, Unrealized Losses	$ (235)		$ (234)