[Line Items] for Accounting Policies [Table]

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Financing Receivable, Historical Collectability Trend Analysis, Period

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Lease Income Recognized On Cash Basis

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Lease Income Recognized On Cash Basis, Number Of Tenants

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Lease Income Recognized On Cash Basis, Percentage Of Aggregate Gross Leasable Area

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Lease Income Recognized On Cash Basis, Percentage Of Total Properties

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Lessor, Lease, Term Of Contract

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Amount of accumulated amortization of debt issuance costs.

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Amount, before accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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Amount of interest capitalized during the period.

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Amount, after allowance for credit loss, of financing receivable. Excludes financing receivable covered under loss sharing agreement.

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Organization and Summary of Significant Accounting Policies (Narrative) (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2021 USD ($) tenant	Mar. 31, 2020 USD ($)	Dec. 31, 2020 USD ($)
Accounting Policies [Line Items]
Interest costs capitalized	$ 63	$ 466
Percentage of total properties for which revenue recognized on cash basis	6.00%
Percentage of aggregate gross leasable area for which revenue recognized on cash basis	8.00%
Percentage of tenants for which revenue recognized on cash basis \| tenant	12
Revenue recognized on cash basis	$ 11,314	$ 203
Mortgage loan
Accounting Policies [Line Items]
Mortgage receivable	2,395		$ 2,482
Allowance for credit loss	$ 153		158
Collectability analysis, period used	15 years
Minimum
Accounting Policies [Line Items]
Initial lease term	10 years
Maximum
Accounting Policies [Line Items]
Initial lease term	20 years
Notes Payable to Banks
Accounting Policies [Line Items]
Debt costs	$ 33,177		31,140
Debt costs accumulated amortization	$ 7,543		$ 9,317