Securities (Summary of Investments) (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Schedule of Available for Sale and Held to Maturty Securities [Line Items]
Available for sale securities amortized cost basis	$ 409,106	$ 373,376
Available for sale securities unrealized gains	9,025	7,203
Available for sale securities unrealized losses	(6,779)	(5,535)
Available for sale, at fair value	411,352	375,044
Held to maturity securities	19,040	20,023
Held to maturity securities unrealized gains	624	493
Held to maturity securities unrealized losses	0	0
Held to maturity securities fair value	19,664	20,516
Total available for sale and held to maturity securities amortized cost	428,146	393,399
Total available for sale and held to maturity securities unrealized gains	9,649	7,696
Total available for sale and held to maturity securities unrealized losses	(6,779)	(5,535)
Total available for sale and held to maturity securities fair value	431,016	395,560
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	97,151	77,330
Available for sale securities unrealized gains	160	73
Available for sale securities unrealized losses	(26)	(388)
Available for sale, at fair value	97,285	77,015
Mortgage-backed securities issued by U.S. government-sponsored agencies and 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	249,141	228,908
Available for sale securities unrealized gains	8,322	6,398
Available for sale securities unrealized losses	0	(450)
Available for sale, at fair value	257,463	234,856
Held to maturity securities	19,040	20,023
Held to maturity securities unrealized gains	624	493
Held to maturity securities unrealized losses	0	0
Held to maturity securities fair value	19,664	20,516
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	31,025	35,353
Available for sale securities unrealized gains	511	727
Available for sale securities unrealized losses	0	0
Available for sale, at fair value	31,536	36,080
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	29,824	29,815
Available for sale securities unrealized gains	0	0
Available for sale securities unrealized losses	(6,743)	(4,677)
Available for sale, at fair value	23,081	25,138
Corporate bonds [Member]
Schedule of Available for Sale and Held to Maturty Securities [Line Items]
Available for sale securities amortized cost basis	1,965	1,970
Available for sale securities unrealized gains	32	5
Available for sale securities unrealized losses	(10)	(20)
Available for sale, at fair value	$ 1,987	$ 1,955

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

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