Securities (Amortized Cost, Unrealized Gross Gains and Losses Recognized in Accumulated Other Comprehensive Income (Loss), and Fair Value of Securities Available-for-Sale) (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 615,537	$ 614,085
Gross Unrealized Gains	8,583	5,885
Gross Unrealized Losses	(8,728)	(13,938)
Total	615,392	606,032
U.S. Treasury and Agency Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	20,000	20,000
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(679)	(1,048)
Total	19,321	18,952
Obligations of State and Political Subdivisions [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	125,265	112,008
Gross Unrealized Gains	4,850	2,388
Gross Unrealized Losses	(159)	(899)
Total	129,956	113,497
Mortgage-backed Securities - Residential [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	469,919	481,724
Gross Unrealized Gains	3,733	3,497
Gross Unrealized Losses	(7,890)	(11,991)
Total	465,762	473,230
Equity Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	353	353
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Total	$ 353	$ 353