Organization and Summary of Significant Accounting Policies (Narrative) (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020 USD ($) numberOfTenants	Sep. 30, 2019 USD ($)	Sep. 30, 2020 USD ($) numberOfTenants	Sep. 30, 2019 USD ($)	Dec. 31, 2019 USD ($)	Jan. 01, 2019 USD ($)
Accounting Policies [Line Items]
Interest costs capitalized	$ 332	$ 327	$ 1,218	$ 797
Accounting Standards Update [Extensible List]				us-gaap:AccountingStandardsUpdate201602Member
Write-off of outstanding receivables and related accrued rent	14,758		14,758
Revenue recognized on cash basis	$ 2,203	$ 0	$ 2,406	$ 0
Percentage of total properties for which revenue recognized on cash basis	4.00%		4.00%
Percentage of aggregate gross leasable area for which revenue recognized on cash basis	6.00%		6.00%
Percentage of tenants for which revenue recognized on cash basis | numberOfTenants	6		6
Cumulative Effect, Period of Adoption, Adjustment [Member]
Accounting Policies [Line Items]
Operating lease – ROU assets						$ 7,735
Operating lease – lease liabilities						$ 10,155
Mortgage loan
Accounting Policies [Line Items]
Mortgage receivable	$ 2,569		$ 2,569
Allowance for credit loss	164		$ 164
Collectability analysis, period used			15 years
Minimum
Accounting Policies [Line Items]
Impact of COVID-19, requested rent deferral			30 days
Impact of COVID-19, requested rent deferral, period of payment			3 months
Initial lease term			10 years
Maximum
Accounting Policies [Line Items]
Impact of COVID-19, requested rent deferral			90 days
Impact of COVID-19, requested rent deferral, period of payment			18 months
Initial lease term			20 years
Notes Payable to Banks
Accounting Policies [Line Items]
Debt costs	31,140		$ 31,140		$ 26,932
Debt costs accumulated amortization	$ 8,705		$ 8,705		$ 8,962