Real Estate (Narrative) (Details) - USD ($)	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Debt Instrument [Line Items]
Accumulated depreciation and amortization on properties	$ 90,424,000		$ 86,970,000
Real estate depreciation expense	4,890,000	$ 6,620,000
Lease future minimum payments 2020	51,375,848
Lease future minimum payments 2021	69,979,774
Lease future minimum payments 2022	62,948,942
Lease future minimum payments 2023	59,715,831
Lease future minimum payments 2024	55,715,947
Lease future minimum payments 2025	51,654,944
Lease future minimum payments there after	594,894,205
Secured Debt
Debt Instrument [Line Items]
Fae value of debt	$ 101,750,000
Interest rate, percent	4.21%

Face (par) amount of debt instrument at time of issuance.

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Amount of lease payments to be received by lessor in fifth fiscal year following latest fiscal year for operating lease. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest statement of financial position date.

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The cumulative amount of depreciation for real estate property held for investment purposes.

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