Note 5 - Investment Securities (Details) - Credit-related Impairment Losses on Securities - USD ($)	3 Months Ended
Mar. 31, 2016	Mar. 31, 2015
Credit-related Impairment Losses on Securities [Abstract]
Beginning Balance, January 1st	$ 930,000	$ 3,966,000
Additional credit-related impairment loss on securities for which an other-than-temporary impairment was previously recognized	1,000	3,000
Reductions for securities paid off during the period	0	0
Reductions for securities sold during the period	0	0
Reductions for securities for which the amount previously recognized in other comprehensive income was recognized in earnings because the Company intends to sell the security	0	0
Ending Balance, March 31st	$ 931,000	$ 3,969,000

No definition available.

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- Definition

This item represents reductions in the cumulative amount of credit losses recognized in earnings for an other than temporary impairment (OTTI) of a debt security because the impaired securities were paid off during the period.

+ References

No definition available.

+ Details

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- Definition

This item represents an increase to the cumulative amount of credit losses recognized in earnings for an other than temporary impairment (OTTI) of a debt security held for which a previous OTTI was recognized and the investor does not intend to sell the debt security and it is not more likely than not that the investor will be required to sell the debt security before recovery of its amortized cost basis.

+ References

+ Details

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- Definition

The cumulative amount of credit losses recognized in earnings related to debt securities held for which a portion of an other than temporary impairment (OTTI) was recognized in other comprehensive income (a component of shareholders' equity).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 8B
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=73527792&loc=SL6284393-111563

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 8B
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=73527792&loc=SL6284393-111563

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- Definition

This item represents reductions in the amount of cumulative losses recognized in earnings for other than temporary impairments (OTTI) for which a portion of the impairment had been recognized in other comprehensive income (a component of shareholders' equity) due to a change in status of the impaired security because of a change in the entity's intent to either sell the impaired security or it has become more likely than not that the entity will be required to sell the security before recovery of its cost basis.

+ References

+ Details

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- Definition

This item represents reductions in the cumulative amount of credit losses recognized in earnings for an other than temporary impairment (OTTI) of a debt security because of the sale of impaired securities during the period.

+ References

+ Details

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