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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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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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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)	3 Months Ended		6 Months Ended
	Jun. 30, 2021 USD ($) tenant	Jun. 30, 2020 USD ($)	Jun. 30, 2021 USD ($) tenant	Jun. 30, 2020 USD ($)	May 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Accounting Policies [Line Items]
Interest costs capitalized	$ 64,000	$ 420,000	$ 127,000	$ 886,000
Percentage of total properties for which revenue recognized on cash basis	6.00%		6.00%
Percentage of aggregate gross leasable area for which revenue recognized on cash basis	8.00%		8.00%
Percentage of tenants for which revenue recognized on cash basis \| tenant	11		11
Revenue recognized on cash basis	$ 13,055,000	$ 0	$ 24,369,000	$ 203,000
Mortgage loan
Accounting Policies [Line Items]
Mortgage receivable	2,210,000		2,210,000			$ 2,482,000
Allowance for credit loss	141,000		$ 141,000			158,000
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
Line of Credit
Accounting Policies [Line Items]
Revolving credit facility borrowing capacity	1,100,000,000		$ 1,100,000,000		$ 900,000,000
Notes Payable to Banks
Accounting Policies [Line Items]
Debt costs	33,177,000		33,177,000			31,140,000
Debt costs accumulated amortization	$ 8,102,000		$ 8,102,000			$ 9,317,000