Note 19 - Fair Value of Financial Instruments - Assets and Liabilities Measured at Fair Value (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Total, estimated fair value	$ 34,339	$ 20,716
Equity investments, at fair value (cost of $1,147 and $1,157, respectively)	187	444
Real estate investments, at fair value (cost of $10,225 and $10,225, respectively)	10,662	10,662
Subordinated debt, at fair value	59,601	50,928
Fair Value, Recurring [Member]
Total, estimated fair value	34,339	20,716
Equity investments, at fair value (cost of $1,147 and $1,157, respectively)	187	444
Limited liability investments, at fair value	18,180	32,811
Real estate investments, at fair value (cost of $10,225 and $10,225, respectively)	10,662	10,662
Total assets	63,368	64,633
Subordinated debt, at fair value	59,601	50,928
Stock-based compensation liabilities	1,306	443
Derivative contract - interest rate swap	65
Total liabilities	60,972	51,371
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Total, estimated fair value	0	0
Equity investments, at fair value (cost of $1,147 and $1,157, respectively)	187	172
Limited liability investments, at fair value	0	0
Real estate investments, at fair value (cost of $10,225 and $10,225, respectively)	0	0
Total assets	187	172
Subordinated debt, at fair value	0	0
Stock-based compensation liabilities	0	0
Derivative contract - interest rate swap	0
Total liabilities	0	0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Total, estimated fair value	34,339	20,716
Equity investments, at fair value (cost of $1,147 and $1,157, respectively)	0	272
Limited liability investments, at fair value	0	0
Real estate investments, at fair value (cost of $10,225 and $10,225, respectively)	0	0
Total assets	34,339	20,988
Subordinated debt, at fair value	59,601	50,928
Stock-based compensation liabilities	0	0
Derivative contract - interest rate swap	65
Total liabilities	59,666	50,928
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Total, estimated fair value	0	0
Equity investments, at fair value (cost of $1,147 and $1,157, respectively)	0	0
Limited liability investments, at fair value	3,744	3,263
Real estate investments, at fair value (cost of $10,225 and $10,225, respectively)	10,662	10,662
Total assets	14,406	13,925
Subordinated debt, at fair value	0	0
Stock-based compensation liabilities	1,306	443
Derivative contract - interest rate swap	0
Total liabilities	1,306	443
Fair Value, Recurring [Member] | Fair Value Measured at Net Asset Value Per Share [Member]
Total, estimated fair value	0	0
Equity investments, at fair value (cost of $1,147 and $1,157, respectively)	0	0
Limited liability investments, at fair value	14,436	29,548
Real estate investments, at fair value (cost of $10,225 and $10,225, respectively)	0	0
Total assets	14,436	29,548
Subordinated debt, at fair value	0	0
Stock-based compensation liabilities	0	0
Derivative contract - interest rate swap	0
Total liabilities	0	0
US Government Agencies Debt Securities [Member]
Total, estimated fair value	15,247	10,104
US Government Agencies Debt Securities [Member] | Fair Value, Recurring [Member]
Total, estimated fair value	15,247	10,104
US Government Agencies Debt Securities [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Total, estimated fair value	0	0
US Government Agencies Debt Securities [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Total, estimated fair value	15,247	10,104
US Government Agencies Debt Securities [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Total, estimated fair value	0	0
US Government Agencies Debt Securities [Member] | Fair Value, Recurring [Member] | Fair Value Measured at Net Asset Value Per Share [Member]
Total, estimated fair value	0	0
US States and Political Subdivisions Debt Securities [Member]
Total, estimated fair value	1,584	1,454
US States and Political Subdivisions Debt Securities [Member] | Fair Value, Recurring [Member]
Total, estimated fair value	1,584	1,454
US States and Political Subdivisions Debt Securities [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Total, estimated fair value	0	0
US States and Political Subdivisions Debt Securities [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Total, estimated fair value	1,584	1,454
US States and Political Subdivisions Debt Securities [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Total, estimated fair value	0	0
US States and Political Subdivisions Debt Securities [Member] | Fair Value, Recurring [Member] | Fair Value Measured at Net Asset Value Per Share [Member]
Total, estimated fair value	0	0
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Total, estimated fair value	8,150	5,394
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member] | Fair Value, Recurring [Member]
Total, estimated fair value	8,150	5,394
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Total, estimated fair value	0	0
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Total, estimated fair value	8,150	5,394
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Total, estimated fair value	0	0
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member] | Fair Value, Recurring [Member] | Fair Value Measured at Net Asset Value Per Share [Member]
Total, estimated fair value	0	0
Asset-backed Securities [Member]
Total, estimated fair value	253
Asset-backed Securities [Member] | Fair Value, Recurring [Member]
Total, estimated fair value	253
Asset-backed Securities [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Total, estimated fair value	0
Asset-backed Securities [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Total, estimated fair value	253
Asset-backed Securities [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Total, estimated fair value	0
Asset-backed Securities [Member] | Fair Value, Recurring [Member] | Fair Value Measured at Net Asset Value Per Share [Member]
Total, estimated fair value	0
Corporate Debt Securities [Member]
Total, estimated fair value	9,105	3,764
Corporate Debt Securities [Member] | Fair Value, Recurring [Member]
Total, estimated fair value	9,105	3,764
Corporate Debt Securities [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Total, estimated fair value	0	0
Corporate Debt Securities [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Total, estimated fair value	9,105	3,764
Corporate Debt Securities [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Total, estimated fair value	0	0
Corporate Debt Securities [Member] | Fair Value, Recurring [Member] | Fair Value Measured at Net Asset Value Per Share [Member]
Total, estimated fair value	0	0
Common Stock [Member] | Fair Value, Recurring [Member]
Equity investments, at fair value (cost of $1,147 and $1,157, respectively)	187	155
Common Stock [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Equity investments, at fair value (cost of $1,147 and $1,157, respectively)	187	155
Common Stock [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Equity investments, at fair value (cost of $1,147 and $1,157, respectively)	0	0
Common Stock [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Equity investments, at fair value (cost of $1,147 and $1,157, respectively)	0	0
Common Stock [Member] | Fair Value, Recurring [Member] | Fair Value Measured at Net Asset Value Per Share [Member]
Equity investments, at fair value (cost of $1,147 and $1,157, respectively)	0	0
Warrant [Member] | Fair Value, Recurring [Member]
Equity investments, at fair value (cost of $1,147 and $1,157, respectively)	0	289
Warrant [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Equity investments, at fair value (cost of $1,147 and $1,157, respectively)	0	17
Warrant [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Equity investments, at fair value (cost of $1,147 and $1,157, respectively)	0	272
Warrant [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Equity investments, at fair value (cost of $1,147 and $1,157, respectively)	0	0
Warrant [Member] | Fair Value, Recurring [Member] | Fair Value Measured at Net Asset Value Per Share [Member]
Equity investments, at fair value (cost of $1,147 and $1,157, respectively)	$ 0	$ 0