The aggregate depreciation from amortized cost basis as a percent.

No definition available.

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- Definition

Number of issuers of debt securities.

+ References

No definition available.

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- Definition

Number of securities.

+ References

No definition available.

+ Details

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- Definition

Represents the number of states investments are held in.

+ References

No definition available.

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- Definition

The percentage of the companies investment portfolio by type of investment.

+ References

No definition available.

+ Details

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- Definition

Number of investment positions in available-for-sale investments in a continuous unrealized loss position for which an other-than-temporary impairment (OTTI) has not been recognized in the income statement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 6
-Subparagraph (b)(3)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27290-111563

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- Definition

Number of investment positions in available-for-sale investments that have been in a continuous unrealized loss position for greater than or equal to a year for which an other-than-temporary impairment (OTTI) has not been recognized in the income statement.

+ References

No definition available.

+ Details

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=84177426&loc=d3e6351-108592

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 20
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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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-Paragraph 21
-Subparagraph (a)
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- Definition

The amount by which the fair value of an investment is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 35
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=82895926&loc=d3e25351-111560

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- Definition

Amount of investments classified as other.

+ 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 210.5-02.12)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.1(f,g))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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Note 2 - Investment Securities (Details Textual) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2017 USD ($)	Jun. 30, 2016 USD ($)	Jun. 30, 2017 USD ($)	Jun. 30, 2016 USD ($)	Dec. 31, 2016 USD ($)
Number of Securities	568		568
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions	212		212
Aggregate Depreciation from Amortized Cost Basis, Percent			0.90%
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions, Greater than or Equal to One Year	30		30
General Obligation Bonds [Member] \| Stockholders' Equity, Total [Member] \| Credit Concentration Risk [Member]
Concentration Risk, Percentage			0.00%		0.00%
Revenue Bonds [Member] \| Stockholders' Equity, Total [Member] \| Credit Concentration Risk [Member]
Concentration Risk, Percentage			0.00%		0.00%
Municipal Bonds [Member] \| General Obligation Bonds [Member]
Number of Issuers	124		124		116
Number of States Investments Held in	21		21		21
Other Investments	$ 107,900		$ 107,900		$ 116,500
Municipal Bonds [Member] \| General Obligation Bonds [Member] \| Aggregate Fair Value Exceeding 5 Million [Member]
Number of States Investments Held in					5
Municipal Bonds [Member] \| General Obligation Bonds [Member] \| Minimum [Member]
Number of States Investments Held in	6		6
Other Investments	$ 5,000		$ 5,000		$ 5,000
Municipal Bonds [Member] \| Revenue Bonds [Member]
Number of Issuers	126		126		120
Number of States Investments Held in	13		13		12
Other Investments	$ 272,200		$ 272,200		$ 255,500
Municipal Bonds [Member] \| Revenue Bonds [Member] \| Aggregate Fair Value Exceeding 5 Million [Member]
Number of States Investments Held in	6		6		6
Municipal Bonds [Member] \| Revenue Bonds [Member] \| Minimum [Member]
Other Investments	$ 5,000		$ 5,000		$ 5,000
Equity Securities [Member]
Percentage of Investment Portfolio	1.00%		1.00%		1.00%
Debt Securities [Member]
Other than Temporary Impairment Losses, Investments	$ 0	$ 0	$ 0	$ 0