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Note 7 - Investments (Details Textual) $ in Thousands		12 Months Ended
Note 7 - Investments (Details Textual) $ in Thousands	Sep. 29, 2022 USD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Jun. 30, 2021 USD ($)
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions		208	138
Long-Term Debt, Gross		$ 125,308	$ 124,097
Proceeds from Sale of Real Estate Held-for-investment, Total		12,150
Notes Payable, Total		0	6,411
Flower [Member]
Proceeds from Sale of Real Estate Held-for-investment, Total	$ 12,200	12,200
Notes Payable, Total	$ 5,900
Gains (Losses) on Sales of Investment Real Estate		1,500
Private Company [Member]
Increase (Decrease) in Debt Securities, Trading, and Equity Securities, FV-NI, Total		0	0
Other-than-temporary Impairment Loss, Debt Securities, Portion Recognized in Earnings		0	0
Loans Payable [Member]
Long-Term Debt, Gross		0	6,411
Loans Payable [Member] \| Net Lease Note [Member]
Long-Term Debt, Gross			9,000
Limited Liability Investments [Member]
Equity Method Investments		983	1,901
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Unfunded Commitments		0
Net Lease [Member]
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures, Total		17,100	18,800
Equity Securities, FV-NI, Realized Gain			1,200
Equity Securities, FV-NI, Unrealized Gain			1,200
Net Lease [Member] \| Notes Payable [Member]
Long-Term Debt, Gross				$ 14,300
Equity Securities, FV-NI, Realized Gain			800
Equity Securities, FV-NI, Unrealized Gain			800
Net Lease [Member] \| Maximum [Member]
Equity Securities without Readily Determinable Fair Value, Impairment Loss, Annual Amount		100	100
Private Company Investments [Member]
Investment Owned, at Fair Value		800	800
Other-than-temporary Impairment Loss, Debt Securities, Portion Recognized in Earnings		$ 0	0
Real Estate Investment [Member] \| Flower [Member]
Investment Owned, at Fair Value			$ 10,700