Investment Securities (Details 1) (USD $)	Jun. 30, 2013	Dec. 31, 2012
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Amortized Cost Basis	$ 241,953,000	$ 327,101,000
Available-for-sale Securities, Gross Unrealized Gains	6,333,000	15,624,000
Available-for-sale Securities, Gross Unrealized Losses	5,710,000	1,186,000
Available-for-sale Securities, Fair Value	242,576,000	341,539,000
Schedule of Held-to-maturity Securities [Line Items]
Held-to-maturity Securities, Amortized Cost	223,503,000	114,805,000
Held-to-maturity Securities, Gross Unrealized Gain	630,000	4,576,000
Held-to-maturity Securities, Unrealized Loss	7,508,000	1,146,000
Held-to-maturity Securities, Fair Value	216,625,000	118,235,000
Fair Value Investment Securities Transferred From AFS To HTM	86,500,000
State And Municipal Held-to-Maturity Securities [Member]
Schedule of Held-to-maturity Securities [Line Items]
Held-to-maturity Securities, Amortized Cost	207,503,000	108,805,000
Held-to-maturity Securities, Gross Unrealized Gain	630,000	4,576,000
Held-to-maturity Securities, Unrealized Loss	6,468,000	146,000
Held-to-maturity Securities, Fair Value	201,665,000	113,235,000
Other Held-to-Maturity Debt Securities [Member]
Schedule of Held-to-maturity Securities [Line Items]
Held-to-maturity Securities, Amortized Cost	16,000,000	6,000,000
Held-to-maturity Securities, Gross Unrealized Gain	0	0
Held-to-maturity Securities, Unrealized Loss	1,040,000	1,000,000
Held-to-maturity Securities, Fair Value	14,960,000	5,000,000
US Government Agencies Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Amortized Cost Basis	15,479,000	15,735,000
Available-for-sale Securities, Gross Unrealized Gains	245,000	660,000
Available-for-sale Securities, Gross Unrealized Losses	204,000	0
Available-for-sale Securities, Fair Value	15,520,000	16,395,000
State and Municipal Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Amortized Cost Basis	160,349,000	213,679,000
Available-for-sale Securities, Gross Unrealized Gains	3,738,000	11,359,000
Available-for-sale Securities, Gross Unrealized Losses	4,853,000	1,152,000
Available-for-sale Securities, Fair Value	159,234,000	223,886,000
Residential Government Sponsored Mortgage Backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Amortized Cost Basis	49,660,000	83,764,000
Available-for-sale Securities, Gross Unrealized Gains	2,044,000	3,155,000
Available-for-sale Securities, Gross Unrealized Losses	548,000	29,000
Available-for-sale Securities, Fair Value	51,156,000	86,890,000
Other Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Amortized Cost Basis	8,465,000	13,923,000
Available-for-sale Securities, Gross Unrealized Gains	306,000	450,000
Available-for-sale Securities, Gross Unrealized Losses	8,000	5,000
Available-for-sale Securities, Fair Value	8,763,000	14,368,000
Corporate Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Amortized Cost Basis	8,000,000
Available-for-sale Securities, Gross Unrealized Gains	0
Available-for-sale Securities, Gross Unrealized Losses	97,000
Available-for-sale Securities, Fair Value	$ 7,903,000

No authoritative reference available.

No definition available.

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This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

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This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents Available-for-sale Securities which consist of all investments in certain debt and equity securities neither classified as trading or held-to-maturity securities. A debt security represents a creditor relationship with an enterprise. Debt securities include, among other items, US Treasury securities, US government securities, municipal securities, corporate bonds, convertible debt, commercial paper, and all securitized debt instruments. An equity security represents an ownership interest in an enterprise or the right to acquire or dispose of an ownership interest in an enterprise at fixed or determinable prices. Equity securities include, among other things, common stock, certain preferred stock, warrant rights, call options, and put options, but do not include convertible debt. An entity may opt to provide the reader with additional narrative text to better understand the nature of investments in debt and equity securities which are categorized as Available-for-sale.

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Amount of investments in debt securities categorized as held-to-maturity valued at amortized cost, excludes other than temporary impairment (OTTI).

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