Organization and Summary of Significant Accounting Policies (Narrative) (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Jan. 01, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Interest costs capitalized	$ 345,000	$ 1,076,000	$ 471,000	$ 1,904,000
Amortization of above and below market leases	173,000	1,417,000	401,000	2,115,000
Revolving credit facility borrowing capacity	900,000,000		900,000,000
Mortgages
Debt Instrument [Line Items]
Debt costs	147,000		147,000			$ 147,000
Debt costs accumulated amortization	81,000		81,000			73,000
Notes Payable to Banks
Debt Instrument [Line Items]
Debt costs	26,932,000		26,932,000			26,932,000
Debt costs accumulated amortization	7,819,000		7,819,000			$ 6,705,000
In-place leases, net
Debt Instrument [Line Items]
Acquired-in-place leases	$ 1,798,000	$ 2,370,000	$ 4,042,000	$ 5,516,000
ASC 842
Debt Instrument [Line Items]
Operating lease – ROU assets					$ 7,735,000
Operating lease – lease liabilities					$ 10,155,000