Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Note 6 - Investments (Details Textual) $ in Thousands	3 Months Ended		6 Months Ended	9 Months Ended		12 Months Ended
Note 6 - Investments (Details Textual) $ in Thousands	Sep. 30, 2021 USD ($)	Sep. 30, 2020 USD ($)	Jun. 30, 2021 USD ($)	Sep. 30, 2021 USD ($)	Sep. 30, 2020 USD ($)	Dec. 31, 2020 USD ($)
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions	104			104		5
Other-than-temporary Impairment Loss, Debt Securities, Portion Recognized in Earnings, Total	$ 0	$ 0		$ 0	$ 117
Long-term Debt, Gross	297,415			297,415		$ 300,667
Investment Owned, at Fair Value	800			800		800
Loss on Sale of Investments						200
Other than Temporary Impairment Losses, Investments, Total				100
Private Company [Member]
Other-than-temporary Impairment Loss, Debt Securities, Portion Recognized in Earnings, Total	0	0		0	700
Net Lease Note [Member] \| Notes Payable [Member]
Long-term Debt, Gross			$ 14,300			9,000
Equity Securities, FV-NI, Realized Gain	800		$ 1,200
Equity Securities, FV-NI, Unrealized Gain	800			1,200
Limited Liability Investments [Member]
Equity Method Investments	3,235			3,235		3,692
Equity Method Investments, Fair Value Disclosure	18,180			18,180		$ 32,811
Limited Liability Investments [Member] \| Maximum [Member]
Equity Method Investment, Other than Temporary Impairment	$ 100	$ 100		$ 100	$ 100