Note 2 - Accounting Policies and Related Matters (Details Textual)	12 Months Ended
	Dec. 31, 2019 USD ($) Office Equipment	Dec. 31, 2018 USD ($)
Summary Of Significant Accounting Policies [Line Items]
Contract assets	$ 0	$ 0
Contract liabilities	568,000	332,000
Below -market lease gross value		0
Below -market lease liabilities gross value	3,500,000
Expenses related to fair value adjustments on derivatives	$ 100,000
Number of office leases | Office	4
Number of equipment leases | Equipment	2
Right of use assets gross	$ 1,400,000
Right of use assets net	1,300,000
Operating lease, liability	$ 1,382,000
Operating lease, liability, Statement of Financial Position [Extensible List]	us-gaap:AccountsPayableAndAccruedLiabilitiesCurrentAndNoncurrent
Deferred Revenue [Member]
Summary Of Significant Accounting Policies [Line Items]
Contract liabilities	$ 200,000	300,000
Intangible Lease Assets [Member]
Summary Of Significant Accounting Policies [Line Items]
Above -market lease gross value	2,600,000	0
In-place lease gross value	17,600,000	$ 0
Accounts Payable and Accrued Liabilities [Member]
Summary Of Significant Accounting Policies [Line Items]
Additional operating liabilities	$ 1,600,000