Securities (Summary of Investments) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Schedule of Available for Sale and Held to Maturty Securities [Line Items]
Available for sale securities amortized cost basis	$ 333,295	$ 351,068
Available for sale securities unrealized gains	12,147	11,630
Available for sale securities unrealized losses	(4,500)	(5,036)
Available for sale, at fair value	340,942us-gaap_AvailableForSaleSecurities	357,662us-gaap_AvailableForSaleSecurities
Held to maturity securities	24,025us-gaap_HeldToMaturitySecurities	25,222us-gaap_HeldToMaturitySecurities
Held to maturity securities unrealized gains	809	786
Held to maturity securities unrealized losses	0	0
Held to maturity securities fair value	24,834	26,008
Total available for sale and held to maturity securities amortized cost	357,320	376,290
Total available for sale and held to maturity securities unrealized gains	12,956	12,416
Total available for sale and held to maturity securities unrealized losses	(4,500)	(5,036)
Total available for sale and held to maturity securities fair value	365,776	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	31,203	31,205
Available for sale securities unrealized gains	98	21
Available for sale securities unrealized losses	0	(54)
Available for sale, at fair value	31,301	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	222,547	235,343
Available for sale securities unrealized gains	10,498	10,023
Available for sale securities unrealized losses	0	0
Available for sale, at fair value	233,045	245,366
Held to maturity securities	24,025	25,222
Held to maturity securities unrealized gains	809	786
Held to maturity securities unrealized losses	0	0
Held to maturity securities fair value	24,834	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	42,664	47,647
Available for sale securities unrealized gains	1,515	1,529
Available for sale securities unrealized losses	0	0
Available for sale, at fair value	44,179	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	30,762	30,753
Available for sale securities unrealized gains	0	0
Available for sale securities unrealized losses	(4,475)	(4,979)
Available for sale, at fair value	26,287	25,774
Corporate bonds [Member]
Schedule of Available for Sale and Held to Maturty Securities [Line Items]
Available for sale securities amortized cost basis	6,119	6,120
Available for sale securities unrealized gains	36	57
Available for sale securities unrealized losses	(25)	(3)
Available for sale, at fair value	$ 6,130	$ 6,174

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

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