Organization and Summary of Significant Accounting Policies (Narrative) (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015	Dec. 31, 2015
Debt Instrument [Line Items]
Interest costs capitalized	$ 316,000	$ 558,000	$ 827,000	$ 948,000
Restricted cash and cash held in escrow	242,000		242,000		$ 601,000
Revolving credit facility borrowing capacity	650,000,000		650,000,000
Mortgages [Member]
Debt Instrument [Line Items]
Debt costs	226,000		226,000		226,000
Debt costs accumulated amortization	108,000		108,000		93,000
Notes Payable to Banks [Member]
Debt Instrument [Line Items]
Debt costs	17,782,000		17,782,000		17,782,000
Debt costs accumulated amortization	$ 5,521,000		$ 5,521,000		$ 4,704,000