Note 2 - Accounting Policies and Related Matters (Details Textual) - USD ($)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Summary Of Significant Accounting Policies [Line Items]
Contract assets	$ 0	$ 0
Contract liabilities	860,000	502,000
Accounts receivable	1,812,000	2,224,000
Component of derivative fair value adjustment	400,000	600,000
Accounts Receivable [Member]
Summary Of Significant Accounting Policies [Line Items]
Accounts receivable	900,000	1,000,000.0
Deferred Revenue [Member]
Summary Of Significant Accounting Policies [Line Items]
Contract liabilities	100,000	100,000
Intangible Lease Assets [Member]
Summary Of Significant Accounting Policies [Line Items]
Above -market lease gross value	4,800,000	2,700,000
In-place lease gross value	30,600,000	18,000,000.0
Unamortized Intangible Lease Liabilities [Member]
Summary Of Significant Accounting Policies [Line Items]
Below -market lease liabilities gross value	$ 4,800,000	$ 3,300,000