The aggregate depreciation from amortized cost basis as a percent.

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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.

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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.

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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
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- Definition

The difference between the carrying value and the sale price of an investment. A gain would be recognized when the sale price of the investment is greater than the carrying value of the investment. This element refers to the Gain included in earnings and not to the cash proceeds of the sale.

+ References

No definition available.

+ Details

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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)
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- Definition

Amount of investments classified as other.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section S99
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-Subparagraph (SX 210.7-03.1(f,g))
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- Definition

Fair value of financial instrument held by the entity for its own account (proprietary securities) for trading or investment purposes that are carried at fair value and pledged to counterparties as collateral for financing transactions.

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-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
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-Paragraph 1A
-Subparagraph (b)(1)(i)
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Note 3 - Investment Securities (Details Textual)	1 Months Ended	12 Months Ended
Note 3 - Investment Securities (Details Textual)	Sep. 30, 2016 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
Number of Securities		613
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions		223
Aggregate Depreciation from Amortized Cost Basis, Percent		0.80%
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions, Greater than or Equal to One Year		110
Other than Temporary Impairment Losses, Investments		$ 0	$ 0	$ 0
Gain on Sale of Investments	$ 4,010,877	67,351	4,845,009	$ 1,045,444
Security Owned and Pledged as Collateral, Fair Value		$ 78,642,843	$ 118,811,905
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		131	116
Other Investments		$ 108,000,000	$ 116,500,000
Number of States Investments Held in		26	21
Municipal Bonds [Member] \| General Obligation Bonds [Member] \| Minimum [Member]
Other Investments		$ 5,000,000	$ 5,000,000
Municipal Bonds [Member] \| General Obligation Bonds [Member] \| Aggregate Fair Value Exceeding 5 Million [Member]
Number of States Investments Held in		6	5
Municipal Bonds [Member] \| Revenue Bonds [Member]
Number of Issuers		145	120
Other Investments		$ 337,300,000	$ 255,500,000
Number of States Investments Held in		16	12
Municipal Bonds [Member] \| Revenue Bonds [Member] \| Minimum [Member]
Other Investments		$ 5,000,000	$ 5,000,000
Municipal Bonds [Member] \| Revenue Bonds [Member] \| Aggregate Fair Value Exceeding 5 Million [Member]
Number of States Investments Held in		7	6
Equity Securities [Member]
Percentage of Investment Portfolio		1.00%	1.00%