Note 4 - Investment Securities (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014
Note 4 - Investment Securities (Details) [Line Items]
Available-for-sale Securities	$ 272,483,000us-gaap_AvailableForSaleSecurities	$ 292,299,000us-gaap_AvailableForSaleSecurities
US Government Agencies Debt Securities [Member]
Note 4 - Investment Securities (Details) [Line Items]
Available-for-sale Securities Pledged as Collateral	9,400,000	9,700,000
Held-to-maturity Securities Pledged as Collateral	508,000	507,000
US States and Political Subdivisions Debt Securities [Member]
Note 4 - Investment Securities (Details) [Line Items]
Number of Investment Securities	58
Available-for-sale Debt Securities, Amortized Cost Basis	53,879,000
Available-for-sale Securities	55,920,000
Municipal General Obligation Bonds [Member] \| Insurance Policy, Assured Guaranty Municipal Corp. [Member] \| PENNSYLVANIA \| Ambridge Area School District [Member]
Note 4 - Investment Securities (Details) [Line Items]
Available-for-sale Debt Securities, Amortized Cost Basis	2,400,000
Available-for-sale Securities	2,400,000
Municipal General Obligation Bonds [Member] \| PENNSYLVANIA
Note 4 - Investment Securities (Details) [Line Items]
Available-for-sale Debt Securities, Amortized Cost Basis	6,492,000
Available-for-sale Securities	6,597,000
Municipal General Obligation Bonds [Member]
Note 4 - Investment Securities (Details) [Line Items]
Available-for-sale Debt Securities, Amortized Cost Basis	39,916,000
Available-for-sale Securities	41,342,000
Municipal Revenue Bonds [Member] \| PENNSYLVANIA \| Philadelphia Authority [Member]
Note 4 - Investment Securities (Details) [Line Items]
Available-for-sale Debt Securities, Amortized Cost Basis	1,800,000
Available-for-sale Securities	1,900,000
Municipal Revenue Bonds [Member] \| PENNSYLVANIA
Note 4 - Investment Securities (Details) [Line Items]
Available-for-sale Debt Securities, Amortized Cost Basis	1,774,000
Available-for-sale Securities	1,871,000
Municipal Revenue Bonds [Member]
Note 4 - Investment Securities (Details) [Line Items]
Available-for-sale Debt Securities, Amortized Cost Basis	13,963,000
Available-for-sale Securities	$ 14,578,000

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The number of investment securities held by the entity.

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No definition available.

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- Definition

This item represents the cost of debt 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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.2)

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- Definition

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

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 25

-Paragraph 1

-Subparagraph (b)

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-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 45

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-URI http://asc.fasb.org/extlink&oid=6871852&loc=d3e26610-111562

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- Definition

The fair value of available-for-sale securities that serve as collateral for borrowings.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 5

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- Definition

The carrying amount of held-to-maturity securities that serve as collateral for borrowings.

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