Securities (Summary of Investments) (Details) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Schedule of Available for Sale and Held to Maturty Securities [Line Items]
Available for sale securities amortized cost basis	$ 397,316	$ 373,376
Available for sale securities unrealized gains	9,801	7,203
Available for sale securities unrealized losses	(5,368)	(5,535)
Available for sale, at fair value	401,749	375,044
Held to maturity securities	17,917	20,023
Held to maturity securities unrealized gains	678	493
Held to maturity securities unrealized losses	0	0
Held to maturity securities fair value	18,595	20,516
Total available for sale and held to maturity securities amortized cost	415,233	393,399
Total available for sale and held to maturity securities unrealized gains	10,479	7,696
Total available for sale and held to maturity securities unrealized losses	(5,368)	(5,535)
Total available for sale and held to maturity securities fair value	420,344	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	72,653	77,330
Available for sale securities unrealized gains	170	73
Available for sale securities unrealized losses	0	(388)
Available for sale, at fair value	72,823	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	267,025	228,908
Available for sale securities unrealized gains	9,268	6,398
Available for sale securities unrealized losses	(29)	(450)
Available for sale, at fair value	276,264	234,856
Held to maturity securities	17,917	20,023
Held to maturity securities unrealized gains	678	493
Held to maturity securities unrealized losses	0	0
Held to maturity securities fair value	18,595	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	25,844	35,353
Available for sale securities unrealized gains	313	727
Available for sale securities unrealized losses	0	0
Available for sale, at fair value	26,157	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	29,833	29,815
Available for sale securities unrealized gains	0	0
Available for sale securities unrealized losses	(5,339)	(4,677)
Available for sale, at fair value	24,494	25,138
Corporate bonds [Member]
Schedule of Available for Sale and Held to Maturty Securities [Line Items]
Available for sale securities amortized cost basis	1,961	1,970
Available for sale securities unrealized gains	50	5
Available for sale securities unrealized losses	0	(20)
Available for sale, at fair value	$ 2,011	$ 1,955

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

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