Note 6 - Below-market Lease Intangibles (Details Textual) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Amortization of Below Market Lease	$ 2,152	$ 1,787	$ 1,769

Amount of amortization of acquired leases acquired as part of a real property acquisition at below market lease rate with a finite life.

No definition available.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration