Note 4 - Acquisitions (Details Textual) - USD ($) $ in Thousands		12 Months Ended
Nov. 08, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Business Combination, Acquisition Related Costs			$ 101	$ 69
Residential Property in Brooklyn, NY [Member]
Business Combination, Consideration Transferred, Total	$ 31,129
Business Combination, Acquisition Related Costs	$ 129

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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-Section 30
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