Securities (Summary of Investments) (Details) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Schedule of Available for Sale and Held to Maturty Securities [Line Items]
Available for sale securities amortized cost basis	$ 346,346	$ 351,068
Available for sale securities unrealized gains	9,355	11,630
Available for sale securities unrealized losses	(4,323)	(5,036)
Available for sale, at fair value	351,378	357,662
Held to maturity securities	22,523	25,222
Held to maturity securities unrealized gains	568	786
Held to maturity securities unrealized losses	0	0
Held to maturity securities fair value	23,091	26,008
Total available for sale and held to maturity securities amortized cost	368,869	376,290
Total available for sale and held to maturity securities unrealized gains	9,923	12,416
Total available for sale and held to maturity securities unrealized losses	(4,323)	(5,036)
Total available for sale and held to maturity securities fair value	374,469	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	61,430	31,205
Available for sale securities unrealized gains	49	21
Available for sale securities unrealized losses	(225)	(54)
Available for sale, at fair value	61,254	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	208,539	235,343
Available for sale securities unrealized gains	8,091	10,023
Available for sale securities unrealized losses	(10)	0
Available for sale, at fair value	216,620	245,366
Held to maturity securities	22,523	25,222
Held to maturity securities unrealized gains	568	786
Held to maturity securities unrealized losses	0	0
Held to maturity securities fair value	23,091	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	39,487	47,647
Available for sale securities unrealized gains	1,187	1,529
Available for sale securities unrealized losses	0	0
Available for sale, at fair value	40,674	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	30,772	30,753
Available for sale securities unrealized gains	16	0
Available for sale securities unrealized losses	(4,064)	(4,979)
Available for sale, at fair value	26,724	25,774
Corporate bonds [Member]
Schedule of Available for Sale and Held to Maturty Securities [Line Items]
Available for sale securities amortized cost basis	6,118	6,120
Available for sale securities unrealized gains	12	57
Available for sale securities unrealized losses	(24)	(3)
Available for sale, at fair value	$ 6,106	$ 6,174

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

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