Mortgage Notes Payable (Mortgage Notes based on their respective Properties) (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Total mortgage notes payable	$ 98,201	$ 107,915
Notes Payable
Debt Instrument [Line Items]
Long term debt	96,003	106,320
Mortgage premiums	2,509	1,921
Net unamortized deferred financing costs	(311)	(326)
Total mortgage notes payable	$ 98,201	107,915
Notes Payable \| Santa Teresa Village
Debt Instrument [Line Items]
Interest rate (percentage)	6.20%
Long term debt	$ 0	10,138
Notes Payable \| Magnolia Shopping Center
Debt Instrument [Line Items]
Interest rate (percentage)	5.50%
Long term debt	$ 8,903	8,951
Notes Payable \| Casitas Plaza Shopping Center
Debt Instrument [Line Items]
Interest rate (percentage)	5.32%
Long term debt	$ 7,271	7,307
Notes Payable \| Riverstone Marketplace
Debt Instrument [Line Items]
Interest rate (percentage)	4.96%
Long term debt	$ 18,329	18,424
Notes Payable \| Fullerton Crossroads
Debt Instrument [Line Items]
Interest rate (percentage)	4.73%
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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