Note 4 - Subordinated Notes Receivable (Details Textual) - USD ($)						1 Months Ended			3 Months Ended	12 Months Ended
	Mar. 13, 2020	Mar. 12, 2020	Mar. 04, 2020	Feb. 28, 2020	Nov. 01, 2019	Jan. 31, 2020	Dec. 31, 2019	Nov. 30, 2019	Jun. 30, 2019	Dec. 31, 2019	Dec. 31, 2018	Mar. 31, 2019	Feb. 07, 2019	Sep. 06, 2018	Mar. 31, 2018	Dec. 31, 2017
Financing Receivable, after Allowance for Credit Loss, Total															$ 7,400,000
Impairment of Notes Receivable										$ 897,000
Proceeds from Collection of Notes Receivable										1,824,000
Investment Income, Interest										1,039,000	943,000
A&R Note [Member]
Financing Receivable, before Allowance for Credit Loss, Total														$ 3,300,000
Second A&R Note [Member]
Financing Receivable, after Allowance for Credit Loss, Total							$ 709,000		$ 1,300,000	709,000	2,364,000
Financing Receivable, before Allowance for Credit Loss, Total							2,564,000			2,564,000	3,376,000		$ 3,200,000
Notes Receivable, Interest Rate													6.00%
Proceeds from Interest Received										141,000	35,000
Impairment of Notes Receivable									$ 897,000	897,000
Second A&R Note [Member] | Loan Parties [Member]
Proceeds from Collection of Finance Receivables					$ 220,000		150,000	$ 200,000		570,000
Forbearance Discontinued Payment, Amount Less the Sum of All Forbearance Period Payments and Payments Made, One					2,230,000
Forbearance Discontinued Payment, Amount Less the Sum of All Forbearance Period Payments and Payments Made, Two					$ 2,530,000
Second A&R Note [Member] | Loan Parties [Member] | Subsequent Event [Member]
Proceeds from Collection of Finance Receivables	$ 750,000	$ 250,000	$ 350,000	$ 200,000		$ 130,000
S&L Note [Member]
Financing Receivable, after Allowance for Credit Loss, Total							2,700,000			2,700,000
Financing Receivable, before Allowance for Credit Loss, Total							$ 3,300,000			3,300,000				$ 4,400,000
Notes Receivable, Interest Rate												10.00%
Interest Paid, Excluding Capitalized Interest, Operating Activities										356,000	141,000
Proceeds from Collection of Notes Receivable										1,011,000	60,000
Investment Income, Interest										$ 162,000	$ 62,000