Securities (Reconciliation of fair value of securities) (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Line Items]
Other than Temporary Impairment Losses, Investments, Reclassification Adjustment of Noncredit Portion Included in Net Income, Availabe-for-sale Securities, before Tax	$ 146,000	$ 230,000
Reconciliation of fair value of securities
Available for sale Securities, Amortized Cost	379,036,000	343,093,000
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax	10,602,000	8,832,000
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	(2,600,000)	(3,371,000)
Available for sale Securities, Fair Value, Total	387,038,000us-gaap_AvailableForSaleSecurities	348,554,000us-gaap_AvailableForSaleSecurities
Held to maturity Securities, Amortized Cost	394,745,000	375,453,000
Held-to-maturity Securities, Accumulated Unrecognized Holding Gain	9,364,000	7,747,000
Held-to-maturity Securities, Accumulated Unrecognized Holding Loss	(1,787,000)	(3,501,000)
Held to Maturity, Fair Value, Total	402,322,000	379,699,000
Amortized Cost	773,781,000	718,546,000
Gross Unrealized Gains	19,966,000	16,579,000
Unrealized Losses Other	4,387,000	(6,872,000)
Fair Value	789,360,000	728,253,000
U. S. Government Agency Securities [Member]
Reconciliation of fair value of securities
Available for sale Securities, Amortized Cost	45,848,000	41,369,000
Available-for-sale Debt Securities, Accumulated Gross Unrealized Gain, before Tax	656,000	139,000
Available-for-sale Debt Securities, Accumulated Gross Unrealized Loss, before Tax	0	(22,000)
Available for sale Securities, Fair Value, Total	46,504,000	41,486,000
U.S. Treasury securities
Reconciliation of fair value of securities
Held to maturity Securities, Amortized Cost	1,010,000	1,010,000
Held-to-maturity Securities, Accumulated Unrecognized Holding Gain	79,000	63,000
Held-to-maturity Securities, Accumulated Unrecognized Holding Loss	0	0
Held to Maturity, Fair Value, Total	1,089,000	1,073,000
Agency mortgage-backed securities
Reconciliation of fair value of securities
Available for sale Securities, Amortized Cost	246,148,000	211,168,000
Available-for-sale Debt Securities, Accumulated Gross Unrealized Gain, before Tax	8,098,000	7,203,000
Available-for-sale Debt Securities, Accumulated Gross Unrealized Loss, before Tax	(157,000)	(693,000)
Available for sale Securities, Fair Value, Total	254,089,000	217,678,000
Held to maturity Securities, Amortized Cost	164,830,000	159,522,000
Held-to-maturity Securities, Accumulated Unrecognized Holding Gain	6,049,000	5,422,000
Held-to-maturity Securities, Accumulated Unrecognized Holding Loss	0	0
Held to Maturity, Fair Value, Total	170,879,000	164,944,000
Agency Collateralized Mortgage Obligations [Member]
Reconciliation of fair value of securities
Available for sale Securities, Amortized Cost	59,896,000	63,059,000
Available-for-sale Debt Securities, Accumulated Gross Unrealized Gain, before Tax	836,000	599,000
Available-for-sale Debt Securities, Accumulated Gross Unrealized Loss, before Tax	(444,000)	(623,000)
Available for sale Securities, Fair Value, Total	60,288,000	63,035,000
Held to maturity Securities, Amortized Cost	221,979,000	207,995,000
Held-to-maturity Securities, Accumulated Unrecognized Holding Gain	3,125,000	2,141,000
Held-to-maturity Securities, Accumulated Unrecognized Holding Loss	(1,787,000)	(3,478,000)
Held to Maturity, Fair Value, Total	223,317,000	206,658,000
State, County, and Municipal Securities [Member]
Reconciliation of fair value of securities
Available for sale Securities, Amortized Cost	4,837,000	5,106,000
Available-for-sale Debt Securities, Accumulated Gross Unrealized Gain, before Tax	140,000	117,000
Available-for-sale Debt Securities, Accumulated Gross Unrealized Loss, before Tax	0	0
Available for sale Securities, Fair Value, Total	4,977,000	5,223,000
Held to maturity Securities, Amortized Cost	424,000	424,000
Held-to-maturity Securities, Accumulated Unrecognized Holding Gain	5,000	4,000
Held-to-maturity Securities, Accumulated Unrecognized Holding Loss	0	0
Held to Maturity, Fair Value, Total	429,000	428,000
Single Issuer Trust Preferred Securities Issued by Banks and Insurers [Member]
Reconciliation of fair value of securities
Available for sale Securities, Amortized Cost	2,901,000	2,913,000
Available-for-sale Debt Securities, Accumulated Gross Unrealized Gain, before Tax	19,000	12,000
Available-for-sale Debt Securities, Accumulated Gross Unrealized Loss, before Tax	(10,000)	(16,000)
Available for sale Securities, Fair Value, Total	2,910,000	2,909,000
Held to maturity Securities, Amortized Cost	1,500,000	1,500,000
Held-to-maturity Securities, Accumulated Unrecognized Holding Gain	8,000
Held-to-maturity Securities, Accumulated Unrecognized Holding Loss	0	(23,000)
Held to Maturity, Fair Value, Total	1,508,000	1,477,000
Pooled trust preferred securities issued by banks and insurers
Reconciliation of fair value of securities
Available for sale Securities, Amortized Cost	7,862,000	7,906,000
Available-for-sale Debt Securities, Accumulated Gross Unrealized Gain, before Tax	179,000	195,000
Available-for-sale Debt Securities, Accumulated Gross Unrealized Loss, before Tax	(1,769,000)	(1,780,000)
Available for sale Securities, Fair Value, Total	6,272,000	6,321,000
Equity securities
Reconciliation of fair value of securities
Available for sale Securities, Amortized Cost	11,544,000	11,572,000
Available-for-sale Debt Securities, Accumulated Gross Unrealized Gain, before Tax	674,000	567,000
Available-for-sale Debt Securities, Accumulated Gross Unrealized Loss, before Tax	(220,000)	(237,000)
Available for sale Securities, Fair Value, Total	11,998,000	11,902,000
Corporate debt securities
Reconciliation of fair value of securities
Held to maturity Securities, Amortized Cost	5,002,000	5,002,000
Held-to-maturity Securities, Accumulated Unrecognized Holding Gain	98,000	117,000
Held-to-maturity Securities, Accumulated Unrecognized Holding Loss	0	0
Held to Maturity, Fair Value, Total	$ 5,100,000	$ 5,119,000

Available for sale securities and held to maturity securities amortized cost.

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Available for sale securities and held to maturity securities gross unrealized losses.

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Available-for-sale securities, other-than-temporary impairment unrealized losses, portion recognized in other comprehensive income.

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Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt securities classified as available-for-sale.

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Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt securities classified as available-for-sale.

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

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Amount of debt and equity financial instruments classified as either held-to-maturity or available-for-sale.

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Amount of accumulated unrealized gain on investments in debt securities classified as held-to-maturity.

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Amount before other than temporary impairment (OTTI) accretion, of investments in debt securities classified as held-to-maturity.

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Fair value of investments in debt securities classified as held-to-maturity.

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