Mortgage Notes Payable (Mortgage Notes based on their respective Properties) (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Total mortgage notes payable	$ 88,264	$ 88,511
Notes Payable
Debt Instrument [Line Items]
Long term debt	86,570	86,708
Mortgage premiums	1,954	2,074
Net unamortized deferred financing costs	(260)	(271)
Total mortgage notes payable	$ 88,264	88,511
Notes Payable \| Casitas Plaza Shopping Center
Debt Instrument [Line Items]
Interest rate (percentage)	5.32%
Long term debt	$ 7,120	7,158
Notes Payable \| Riverstone Marketplace
Debt Instrument [Line Items]
Interest rate (percentage)	4.96%
Long term debt	$ 17,950	18,050
Notes Payable \| Fullerton Crossroads
Debt Instrument [Line Items]
Interest rate (percentage)	4.728%
Long term debt	$ 26,000	26,000
Notes Payable \| 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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