Mortgage Notes Payable, Credit Facilities and Senior Notes (Mortgage Notes based on their respective Properties) (Details) - Notes Payable - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Long term debt	$ 86,015	$ 86,157
Mortgage premiums	1,473	1,594
Net unamortized deferred financing costs	(217)	(228)
Total mortgage notes payable	$ 87,271	87,523
Casitas Plaza Shopping Center
Debt Instrument [Line Items]
Interest rate (percentage)	5.32%
Long term debt	$ 6,960	7,001
Riverstone Marketplace
Debt Instrument [Line Items]
Interest rate (percentage)	4.96%
Long term debt	$ 17,555	17,656
Fullerton Crossroads
Debt Instrument [Line Items]
Interest rate (percentage)	4.728%
Long term debt	$ 26,000	26,000
Diamond Hills Plaza
Debt Instrument [Line Items]
Interest rate (percentage)	3.55%
Long term debt	$ 35,500	$ 35,500

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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