Fair Value (Additional Information) (Details) (USD $)	3 Months Ended	12 Months Ended
Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loan held for sale, at fair value	$ 6,290,000us-gaap_LoansHeldForSaleMortgages		$ 6,311,000us-gaap_LoansHeldForSaleMortgages
Contractual principal balance of Loan held for sale	6,207,000		6,227,000
Difference in amount of loan held for sale	83,000		84,000
Valuation allowance for loans losses	1,579,000		1,542,000
Cost of real estate sales	0us-gaap_CostOfRealEstateSales	0us-gaap_CostOfRealEstateSales	104,000us-gaap_CostOfRealEstateSales
Other real estate, carrying value	0us-gaap_RealEstateGrossAtCarryingValue		68,000us-gaap_RealEstateGrossAtCarryingValue
Fair Value, Measurements, Recurring
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Securities	619,578,000		630,995,000
Significant Unobservable Inputs (Level 3) \| Fair Value, Measurements, Recurring
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Securities	9,955,000		10,494,000
Obligations of State and Political Subdivisions
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total Gains or Losses (realized/unrealized) Included in Earnings	36,000	69,000
Obligations of State and Political Subdivisions \| Fair Value, Measurements, Recurring
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Securities	158,800,000		153,777,000
Total Gains or Losses (realized/unrealized) Included in Earnings	36,000	69,000
Obligations of State and Political Subdivisions \| Significant Unobservable Inputs (Level 3) \| Fair Value, Measurements, Recurring
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Securities	9,602,000		10,141,000
Equity Securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total Gains or Losses (realized/unrealized) Included in Earnings	0	0
Equity Securities \| Fair Value, Measurements, Recurring
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Securities	353,000		353,000
Total Gains or Losses (realized/unrealized) Included in Earnings	0	0
Equity Securities \| Significant Unobservable Inputs (Level 3) \| Fair Value, Measurements, Recurring
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Securities	353,000		353,000
Commercial Real Estate
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Impaired loans, carrying amount	3,300,000		3,043,000
Valuation allowance for loans losses	1,539,000		1,539,000
Provision for loan losses	37,000		261,000
Provision for loan lease and other losses		$ 863,000

Contractual Amounts of Financial Instrument

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Amount of other addition (reduction) in allowance reserve for credit loss.

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Reflects for the period the total of the carrying amount of the commercial, industrial and residential land and buildings sold plus certain overhead and other costs incurred to place the real estate in saleable condition, capitalized interest costs in the properties sold, and inventory impairment losses recognized. This element would most likely be used by an entity whose principal activities involve real estate or which has significant real estate operations.

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Amount of gain (loss) recognized in the income statement for financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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For loans held as assets for which the fair value option has been elected, this item represents the difference between the aggregate fair value and the aggregate unpaid principal balance of those loans that are 90 days or more past due, in nonaccrual status, or both.

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Amount of allowance for credit losses related to recorded investment.

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Unpaid principal balance of impaired financing receivables for which there is a related allowance for credit losses.

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Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

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Amount of mortgage loans held for sale. Excludes loans and leases covered under loss sharing agreements and loans classified as debt securities.

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Amount of expense related loan transactions, lease transactions, credit loss from transactions other than loan and lease transactions, and other loss based on assessment of uncollectability from the counterparty to reduce the account to their net realizable value.

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Amount, before accumulated depreciation, of real estate investments for entities with a substantial portion of business acquiring and holding investment real estate.

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