Note 4 - Investments - Marketable Securities (Details) - USD ($)	Jun. 30, 2015	Dec. 31, 2014
Corporate Bond Securities [Member]
Amortized Cost	$ 3,018,070
Unrealized Gains
Unrealized Losses	$ (4,920)
Fair Value	3,013,150
Certificates of Deposit [Member]
Amortized Cost	$ 15,500,000	$ 6,750,000
Unrealized Gains
Unrealized Losses
Fair Value	$ 15,500,000	$ 6,750,000
Amortized Cost	$ 18,518,070
Unrealized Gains
Unrealized Losses	$ (4,920)
Fair Value	$ 18,513,150

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

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 25

-Paragraph 1

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-Publisher FASB

-Name Accounting Standards Codification

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Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 10

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Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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This item represents the cost of debt and equity 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.

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