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

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Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

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Average number of shares or units issued and outstanding that are used in calculating basic and diluted earnings per share (EPS).

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Note 1 - Description of Business and Significant Accounting Policies (Details Textual)	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2020 USD ($) $ / shares shares	Sep. 30, 2019 USD ($) shares	Sep. 30, 2020 USD ($) $ / shares shares	Sep. 30, 2019 USD ($) shares	Dec. 31, 2019 USD ($) $ / shares shares	Jun. 30, 2020 USD ($)	Jun. 30, 2019 USD ($)	Dec. 31, 2018 USD ($)
Number of Wholly-Owned Operating Subsidiaries	5		5
Common Stock, Par or Stated Value Per Share (in dollars per share) \| $ / shares	$ 0.10		$ 0.10		$ 0.10
Common Stock, Shares Authorized (in shares) \| shares	20,000,000		20,000,000		20,000,000
Common Stock, Shares, Issued, Total (in shares) \| shares	7,741,358		7,741,358		7,734,004
Weighted Average Number of Shares Outstanding, Basic and Diluted (in shares) \| shares	7,741,272	7,715,583	7,738,179	7,681,612
Equity Securities, FV-NI					$ 10,987,539
Equity Securities, FV-NI, Unrealized Gain (Loss), Total			$ (126,205)	$ 951,575	1,098,760
Stockholders' Equity Attributable to Parent, Ending Balance	$ 16,475,696	$ 16,869,867	$ 16,475,696	16,869,867	16,876,197	$ 14,885,772	$ 15,719,498	$ 12,632,666
Equity Securities, FV-NI, Gain (Loss), Total					$ 1,100,000
Common Stock, Shares, Outstanding, Ending Balance (in shares) \| shares	7,741,358		7,741,358		7,734,004
AOCI Attributable to Parent [Member]
Stockholders' Equity Attributable to Parent, Ending Balance	$ 4,079,967	2,494,848	$ 4,079,967	2,494,848	$ 2,329,495	3,517,249	1,502,174	(2,184,429)
Retained Earnings [Member]
Stockholders' Equity Attributable to Parent, Ending Balance	$ (11,494,544)	$ (9,652,632)	$ (11,494,544)	$ (9,652,632)	(9,436,956)	$ (12,566,699)	$ (9,695,078)	(8,937,404)
Cumulative Effect, Period of Adoption, Adjustment [Member]
Stockholders' Equity Attributable to Parent, Ending Balance
Cumulative Effect, Period of Adoption, Adjustment [Member] \| AOCI Attributable to Parent [Member]
Stockholders' Equity Attributable to Parent, Ending Balance								1,098,760
Cumulative Effect, Period of Adoption, Adjustment [Member] \| Retained Earnings [Member]
Stockholders' Equity Attributable to Parent, Ending Balance								$ (1,098,760)
Accounting Standards Update 2016-01 [Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member] \| AOCI Attributable to Parent [Member]
Stockholders' Equity Attributable to Parent, Ending Balance					(1,098,760)
Accounting Standards Update 2016-01 [Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member] \| Retained Earnings [Member]
Stockholders' Equity Attributable to Parent, Ending Balance					$ (1,098,760)