Investment Securities (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013		Dec. 31, 2012		Sep. 30, 2012
Available-for-sale securities [Abstract]
Fair/Book Value, Total	$ 421,765		$ 417,991		$ 463,177
Held To Maturity Securities [Abstract]
Book Value	70,961		68,392		68,960
Fair Value	71,186
Available-for-sale Securities [Member]
Available-for-sale securities [Abstract]
Amortized Cost	422,347		405,914		447,408
Gross Unrealized Gains	5,417		12,099		15,769
Gross Unrealized Losses	5,999		22		0
Fair/Book Value, Total	421,765		417,991		463,177
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Less Than 12 Months Fair Value	149,079		7,984
12 Months or More Fair Value	0		0
Total Fair Value	149,079		7,984
Less Than 12 Months Unrealized Loss	5,999		22
Total Unrealized Loss	5,999		22
12 Months or More Unrealized Loss	0		0
Held-to-maturity Securities [Member]
Held To Maturity Securities [Abstract]
Book Value	70,961		68,392		68,960
Gross Unrealized Gains	966		2,308		2,643
Gross Unrealized Losses	741		3		0
Fair Value	71,186		70,697		71,603
Held-to-maturity Securities, Continuous Unrealized Loss Position [Abstract]
Less than Twelve Months Fair Value	9,411		528
Twelve Months or More Fair Value	0		0
Total Fair Value	9,411		528
Less than 12 Months Unrealized Loss	741		3
12 Months or Longer Unrealized Loss	0		0
Total Unrealized Loss	741		3		0
Government Agency & Government Sponsored Entities [Member] | Available-for-sale Securities [Member]
Available-for-sale securities [Abstract]
Amortized Cost	28,404		26,546		46,655
Gross Unrealized Gains	239		277		316
Gross Unrealized Losses	0		0		0
Fair/Book Value, Total	28,643		26,823		46,971
Obligations of States and Political Subdivisions [Member] | Available-for-sale Securities [Member]
Available-for-sale securities [Abstract]
Amortized Cost			5,665		5,704
Gross Unrealized Gains			0		0
Gross Unrealized Losses			0		0
Fair/Book Value, Total			5,665		5,704
Obligations of States and Political Subdivisions [Member] | Held-to-maturity Securities [Member]
Held To Maturity Securities [Abstract]
Book Value	67,717		65,694		66,098
Gross Unrealized Gains	965		2,296		2,623
Gross Unrealized Losses	741		3		0
Fair Value	67,941		67,987		68,721
Held-to-maturity Securities, Continuous Unrealized Loss Position [Abstract]
Less than Twelve Months Fair Value	9,411		528
Twelve Months or More Fair Value	0		0
Total Fair Value	9,411		528
Less than 12 Months Unrealized Loss	741		3
12 Months or Longer Unrealized Loss	0		0
Total Unrealized Loss	741		3		0
Mortgage Backed Securities [Member] | Available-for-sale Securities [Member]
Available-for-sale securities [Abstract]
Amortized Cost	342,963	[1]	341,212	[1]	374,582	[1]
Gross Unrealized Gains	4,928	[1]	11,570	[1]	15,230	[1]
Gross Unrealized Losses	5,814	[1]	10	[1]	0	[1]
Fair/Book Value, Total	342,077	[1]	352,772	[1]	389,812	[1]
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Less Than 12 Months Fair Value	129,198		4,542
12 Months or More Fair Value	0		0
Total Fair Value	129,198		4,542
Less Than 12 Months Unrealized Loss	5,814		10
Total Unrealized Loss	5,814		10
12 Months or More Unrealized Loss	0		0
Mortgage Backed Securities [Member] | Held-to-maturity Securities [Member]
Held To Maturity Securities [Abstract]
Book Value	121	[1]	484	[1]	640	[1]
Gross Unrealized Gains	1	[1]	12	[1]	20	[1]
Gross Unrealized Losses	0	[1]	0	[1]	0	[1]
Fair Value	122	[1]	496	[1]	660	[1]
Held-to-maturity Securities, Continuous Unrealized Loss Position [Abstract]
Total Unrealized Loss	0	[1]	0	[1]	0	[1]
Corporate Securities [Member] | Available-for-sale Securities [Member]
Available-for-sale securities [Abstract]
Amortized Cost	49,696		22,318		14,641
Gross Unrealized Gains	250		252		223
Gross Unrealized Losses	185		12		0
Fair/Book Value, Total	49,761		22,558		14,864
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Less Than 12 Months Fair Value	19,881		3,442
12 Months or More Fair Value	0		0
Total Fair Value	19,881		3,442
Less Than 12 Months Unrealized Loss	185		12
Total Unrealized Loss	185		12
12 Months or More Unrealized Loss	0		0
Other [Member] | Available-for-sale Securities [Member]
Available-for-sale securities [Abstract]
Amortized Cost	1,284		10,173		5,826
Gross Unrealized Gains	0		0		0
Gross Unrealized Losses	0		0		0
Fair/Book Value, Total	1,284		10,173		5,826
Other [Member] | Held-to-maturity Securities [Member]
Held To Maturity Securities [Abstract]
Book Value	3,123		2,214		2,222
Gross Unrealized Gains	0		0		0
Gross Unrealized Losses	0		0		0
Fair Value	3,123		2,214		2,222
Held-to-maturity Securities, Continuous Unrealized Loss Position [Abstract]
Total Unrealized Loss	$ 0		$ 0		$ 0

[1] All Mortgage Backed Securities consist of securities collateralized by residential real estate and were issued by an agency or government sponsored entity of the U.S. government.