Organization and Summary of Significant Accounting Policies (Narrative) (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Debt Instrument [Line Items]
Interest costs capitalized	$ 1,076,000	$ 560,000	$ 1,904,000	$ 1,113,000
Amortization of above and below market leases	1,417,000	682,000	2,115,000	1,341,000
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	64,000		64,000		55,000
Notes Payable to Banks
Debt Instrument [Line Items]
Debt costs	22,682,000		22,682,000		22,682,000
Debt costs accumulated amortization	7,399,000		7,399,000		$ 6,337,000
In-place leases, net
Debt Instrument [Line Items]
Acquired-in-place leases	$ 2,370,000	$ 3,281,000	$ 5,516,000	$ 6,608,000