Real Estate (Narrative) (Details)	3 Months Ended	6 Months Ended
Jun. 30, 2021 USD ($) officeBuilding	Jun. 30, 2021 USD ($)	Jun. 30, 2020 USD ($)	Dec. 31, 2020 USD ($)
Debt Instrument [Line Items]
Accumulated depreciation and amortization on properties	$ 64,226,000	$ 64,226,000		$ 86,970,000
Real estate depreciation expense		9,622,000	$ 13,776,000
Lease future minimum payments 2021	29,265,862	29,265,862
Lease future minimum payments 2022	59,450,838	59,450,838
Lease future minimum payments 2023	53,607,393	53,607,393
Lease future minimum payments 2024	52,500,378	52,500,378
Lease future minimum payments 2025	50,115,697	50,115,697
Lease future minimum payments 2026	47,602,823	47,602,823
Lease future minimum payments there after	$ 597,389,153	597,389,153
Number of real estate properties sold \| officeBuilding	2
Secured Debt
Debt Instrument [Line Items]
Fae value of debt	$ 102	$ 102

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

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