Securities (Summary of Investments) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Schedule of Available for Sale and Held to Maturity Securities [Line Items]
Available for sale securities amortized cost	$ 351,068	$ 387,910
Available for sale securities unrealized gains	11,630	11,520
Available for sale securities unrealized losses	(5,036)	(6,527)
Available for sale, at fair value	357,662us-gaap_AvailableForSaleSecurities	392,903us-gaap_AvailableForSaleSecurities
Held to maturity securities amortized cost	25,222us-gaap_HeldToMaturitySecurities	29,905us-gaap_HeldToMaturitySecurities
Held to maturity securities unrealized gains	786	14
Held to Matruity securities unrealized losses	0	(54)
Held to maturity securities fair value	26,008	29,865
Total securities amortized cost	376,290	417,815
Total securities unrealized gains	12,416	11,534
Total securities unrealized losses	(5,036)	(6,581)
Total securities fair value	383,670	422,768
Available for sale securities amortized cost	351,068
Obligations of U.S. government-sponsored enterprises [Member]
Schedule of Available for Sale and Held to Maturity Securities [Line Items]
Available for sale securities amortized cost	31,205	54,474
Available for sale securities unrealized gains	21	720
Available for sale securities unrealized losses	(54)	(79)
Available for sale, at fair value	31,172	55,115
Available for sale securities amortized cost	31,205
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 Maturity Securities [Line Items]
Available for sale securities amortized cost	235,343	230,387
Available for sale securities unrealized gains	10,023	8,369
Available for sale securities unrealized losses	0	(401)
Available for sale, at fair value	245,366	238,355
Held to maturity securities amortized cost	25,222	29,905
Held to maturity securities unrealized gains	786	14
Held to Matruity securities unrealized losses	0	(54)
Held to maturity securities fair value	26,008	29,865
Available for sale securities amortized cost	235,343
Obligations of states and political subdivisions [Member]
Schedule of Available for Sale and Held to Maturity Securities [Line Items]
Available for sale securities amortized cost	47,647	60,659
Available for sale securities unrealized gains	1,529	2,200
Available for sale securities unrealized losses	0	0
Available for sale, at fair value	49,176	62,859
Available for sale securities amortized cost	47,647
Trust preferred securities: Individual name issuers [Member]
Schedule of Available for Sale and Held to Maturity Securities [Line Items]
Available for sale securities amortized cost	30,753	30,715
Available for sale securities unrealized gains	0	0
Available for sale securities unrealized losses	(4,979)	(6,031)
Available for sale, at fair value	25,774	24,684
Trust preferred securities: Collateralized debt obligations [Member]
Schedule of Available for Sale and Held to Maturity Securities [Line Items]
Available for sale securities amortized cost		547
Available for sale securities unrealized gains		0
Available for sale securities unrealized losses		0
Available for sale, at fair value		547
Corporate bonds [Member]
Schedule of Available for Sale and Held to Maturity Securities [Line Items]
Available for sale securities amortized cost	6,120	11,128
Available for sale securities unrealized gains	57	231
Available for sale securities unrealized losses	(3)	(16)
Available for sale, at fair value	6,174	11,343
Available for sale securities amortized cost	$ 6,120

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