Note 6 - Fair Value of Financial Instruments - Summary of Financial Instruments (Details) - USD ($)	Dec. 31, 2018	Dec. 31, 2017
Reported Value Measurement [Member]
Note receivable	$ 1,405,112	$ 1,521,005
Marketable securities	339,000	330,000
Long-term debt		3,045,421
Estimate of Fair Value Measurement [Member]
Note receivable	1,529,000	1,684,000
Marketable securities	339,000	330,000
Long-term debt		3,045,421
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 1 [Member]
Note receivable
Marketable securities	339,000	330,000
Long-term debt
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 2 [Member]
Note receivable	1,529,000	1,684,000
Marketable securities
Long-term debt		3,045,421
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 3 [Member]
Note receivable
Marketable securities
Long-term debt

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

No definition available.

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- Definition

Fair value portion of an agreement for an unconditional promise by the maker to pay the holder a definite sum of money at a future date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.3(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Amount of investment in debt security measured at fair value with change in fair value recognized in net income (trading) and investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.4)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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