Securities (Summary of Investments) (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Schedule of Available for Sale and Held to Maturty Securities [Line Items]
Available for sale securities amortized cost basis	$ 318,219	$ 351,068
Available for sale securities unrealized gains	9,708	11,630
Available for sale securities unrealized losses	(4,132)	(5,036)
Available for sale, at fair value	323,795	357,662
Held to maturity securities	21,140	25,222
Held to maturity securities unrealized gains	680	786
Held to maturity securities unrealized losses	0	0
Held to maturity securities fair value	21,820	26,008
Total available for sale and held to maturity securities amortized cost	339,359	376,290
Total available for sale and held to maturity securities unrealized gains	10,388	12,416
Total available for sale and held to maturity securities unrealized losses	(4,132)	(5,036)
Total available for sale and held to maturity securities fair value	345,615	383,670
Obligations of U.S. government-sponsored enterprises [Member]
Schedule of Available for Sale and Held to Maturty Securities [Line Items]
Available for sale securities amortized cost basis	52,430	31,205
Available for sale securities unrealized gains	220	21
Available for sale securities unrealized losses	(7)	(54)
Available for sale, at fair value	52,643	31,172
Mortgage-backed securities issued by US Government-sponsored enterprises [Member]
Schedule of Available for Sale and Held to Maturty Securities [Line Items]
Available for sale securities amortized cost basis	197,790	235,343
Available for sale securities unrealized gains	8,498	10,023
Available for sale securities unrealized losses	0	0
Available for sale, at fair value	206,288	245,366
Held to maturity securities	21,140	25,222
Held to maturity securities unrealized gains	680	786
Held to maturity securities unrealized losses	0	0
Held to maturity securities fair value	21,820	26,008
Obligations of states and political subdivisions [Member]
Schedule of Available for Sale and Held to Maturty Securities [Line Items]
Available for sale securities amortized cost basis	36,775	47,647
Available for sale securities unrealized gains	982	1,529
Available for sale securities unrealized losses	0	0
Available for sale, at fair value	37,757	49,176
Individual name issuer trust preferred debt securities
Schedule of Available for Sale and Held to Maturty Securities [Line Items]
Available for sale securities amortized cost basis	29,806	30,753
Available for sale securities unrealized gains	0	0
Available for sale securities unrealized losses	(4,123)	(4,979)
Available for sale, at fair value	25,683	25,774
Corporate bonds [Member]
Schedule of Available for Sale and Held to Maturty Securities [Line Items]
Available for sale securities amortized cost basis	1,418	6,120
Available for sale securities unrealized gains	8	57
Available for sale securities unrealized losses	(2)	(3)
Available for sale, at fair value	$ 1,424	$ 6,174

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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