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Transaction costs.

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REAL ESTATE INVESTMENTS (Details Narrative)					3 Months Ended		12 Months Ended
REAL ESTATE INVESTMENTS (Details Narrative)	Jan. 28, 2022 USD ($) a ft²	Nov. 19, 2021	Oct. 27, 2021 USD ($) a ft²	Jun. 01, 2021	Dec. 31, 2021 USD ($) ft² $ / shares	Dec. 31, 2020 ft²	Sep. 30, 2021 USD ($) ft²
Real Estate [Line Items]
Transaction costs					$ 29,000
Series C Cumulative Redeemable Preferred Stock [Member]
Real Estate [Line Items]
Cumulative redeemable preferred, stock dividend rate					6.125%
Preferred stock, par value \| $ / shares					$ 0.01
Series C Cumulative Redeemable Preferred Stock [Member]
Real Estate [Line Items]
Cumulative redeemable preferred, stock dividend rate					6.125%
Four Parking Expansions [Member]
Real Estate [Line Items]
New Lease term					6 years 8 months 12 days
Project cost					$ 13,700,000
Increase in annual rent					1,300,000
Six Parking Expansions [Member]
Real Estate [Line Items]
Project cost					$ 31,400,000
FedEx Ground Package System, Inc. [Member] \| Straight Line Rents [Member]
Real Estate [Line Items]
Change in Lease terms after expansion		In addition, the expansion resulted in a new 14.5 year lease which extended the prior lease expiration date from May 2031 to May 2036. Furthermore, annual rent will increase by 1.9% on June 1, 2026 resulting in an annualized rent of approximately $2.76 million, or $8.78 per square foot from November 19, 2021 through the remaining term of the lease.
Olathe, KS [Member] \| FedEx Ground Package System, Inc. [Member] \| Straight-Line Rent [Member]
Real Estate [Line Items]
New Lease term		14 years 6 months
New lease term expiration period		May 2031 to May 2036
Rent, annual increase percentage		1.90%
Wheeling (IL) [Member] \| FedEx Ground Package System, Inc. [Member] \| Straight Line Rents [Member]
Real Estate [Line Items]
Current tenant lease agreement expansion, description					In addition, the expansion resulted in a new 9.8 year lease which extended the prior lease expiration date from May 2027 to August 2031.
Wheeling (IL) [Member] \| FedEx Ground Package System, Inc. [Member] \| Straight-Line Rent [Member]
Real Estate [Line Items]
New Lease term		9 years 9 months 18 days
New lease term expiration period		May 2027 to August 2031
Sauget [Member] \| FedEx Ground Package System, Inc. [Member] \| Straight Line Rents [Member]
Real Estate [Line Items]
Change in Lease terms after expansion					In addition, the expansion resulted in a new 13.8 year lease which extended the prior lease expiration date from May 2029 to August 2035. Furthermore, annual rent will increase by 3.7% on June 1, 2029 resulting in an annualized rent from November 10, 2021 through the remaining term of the lease of approximately $1.40 million, or $7.07 per square foot.
Sauget [Member] \| FedEx Ground Package System, Inc. [Member] \| Straight-Line Rent [Member]
Real Estate [Line Items]
New Lease term					13 years 9 months 18 days
New lease term expiration period					May 2029 to August 2035
Rent, annual increase percentage					3.70%
Orion MI [Member] \| FedEx Ground Package System, Inc. [Member] \| Straight Line Rents [Member]
Real Estate [Line Items]
Change in Lease terms after expansion					In addition, the expansion resulted in a new 9.9 year lease which extended the prior lease expiration date from June 2023 to October 2031.
Orion MI [Member] \| FedEx Ground Package System, Inc. [Member] \| Straight-Line Rent [Member]
Real Estate [Line Items]
New Lease term					9 years 10 months 24 days
New lease term expiration period					June 2023 to October 2031
FedEx Ground Package System, Inc. [Member]
Real Estate [Line Items]
New Lease term					15 years
Project cost					$ 2,300,000		$ 3,400,000
Increase in annual rent					185,000		340,000
Annualized Rent							$ 2,560,000
Annual rent per square foot \| ft²							8.15
Rent, annual increase percentage				2.10%			2.10%
FedEx Ground Package System, Inc. [Member] \| Wheeling (IL) [Member]
Real Estate [Line Items]
Project cost					1,000,000.0
Increase in annual rent					105,000
FedEx Ground Package System, Inc. [Member] \| Sauget [Member]
Real Estate [Line Items]
Project cost					3,800,000
Increase in annual rent					346,000
FedEx Ground Package System, Inc. [Member] \| Orion MI [Member]
Real Estate [Line Items]
Project cost					6,500,000
Increase in annual rent					651,000
FedEx Ground Package System, Inc. [Member] \| Minimum [Member] \| Olathe, KS [Member]
Real Estate [Line Items]
Annualized Rent					$ 2,530,000		$ 2,140,000
Annual rent per square foot \| ft²					8.08		6.83
FedEx Ground Package System, Inc. [Member] \| Minimum [Member] \| Wheeling (IL) [Member]
Real Estate [Line Items]
Annualized Rent					$ 1,270,000
Annual rent per square foot \| ft²					10.34
FedEx Ground Package System, Inc. [Member] \| Minimum [Member] \| Sauget [Member]
Real Estate [Line Items]
Annualized Rent					$ 1,040,000.00
Annual rent per square foot \| ft²					5.21
FedEx Ground Package System, Inc. [Member] \| Minimum [Member] \| Orion MI [Member]
Real Estate [Line Items]
Annualized Rent					$ 1,910,000
Annual rent per square foot \| ft²					7.77
FedEx Ground Package System, Inc. [Member] \| Maximum [Member] \| Olathe, KS [Member]
Real Estate [Line Items]
Annualized Rent					$ 2,720,000		$ 2,480,000
Annual rent per square foot \| ft²					8.67		7.91
FedEx Ground Package System, Inc. [Member] \| Maximum [Member] \| Wheeling (IL) [Member]
Real Estate [Line Items]
Annualized Rent					$ 1,380,000
Annual rent per square foot \| ft²					11.19
FedEx Ground Package System, Inc. [Member] \| Maximum [Member] \| Sauget [Member]
Real Estate [Line Items]
Annualized Rent					$ 1,380,000
Annual rent per square foot \| ft²					6.95
FedEx Ground Package System, Inc. [Member] \| Maximum [Member] \| Orion MI [Member]
Real Estate [Line Items]
Annualized Rent					$ 2,560,000
Annual rent per square foot \| ft²					10.42
FedEx Ground Package System, Inc. [Member] \| Industrial Buildings [Member]
Real Estate [Line Items]
Purchase of industrial building \| ft²			291,000
Area of property \| a			46.0
Percentage of building area leased			100.00%
New Lease term			15 years
New lease term expiration period			July 2036
Purchase price of industrial building			$ 30,200,000
Annual rental revenue			$ 1,700,000
Mercedes Benz US International, Inc [Member] \| Industrial Buildings [Member] \| Subsequent Event [Member]
Real Estate [Line Items]
Purchase of industrial building \| ft²	530,000
Area of property \| a	53.5
Percentage of building area leased	100.00%
New Lease term	10 years
New lease term expiration period	November 2031
Purchase price of industrial building	$ 51,700,000
Annual rental revenue	$ 3,300,000
FedEx and Fedex Subsidiaries [Member]
Real Estate [Line Items]
Square feet (in millions) of real estate property leased \| ft²					11,900,000	11,200,000
Weighted average lease maturity					8 years 1 month 6 days
Percentage of real estate property leased					47.00%	46.00%
FedEx Corporation [Member]
Real Estate [Line Items]
Percentage of real estate property leased					4.00%	5.00%
Percentage of rental space and tenant account, description					As of December 31, 2021, the only tenants, other than FDX and its subsidiaries, that leased 5% or more of our total square footage were subsidiaries of Amazon.com, Inc (Amazon), which consists of five separate stand-alone leases for properties located in four different states, containing 1.5 million total square feet
FedEx Corporation Subsidiaries [Member]
Real Estate [Line Items]
Percentage of real estate property leased					43.00%	41.00%
Amazon.com Services, Inc. [Member]
Real Estate [Line Items]
Square feet (in millions) of real estate property leased \| ft²					1,500,000
Percentage of rentable square feet					6% of our total leasable square feet
Fdx And Subsidiaries [Member] \| Rental and Reimbursement Revenue [Member]
Real Estate [Line Items]
Percentage of rental space and tenant account, description					The only tenants, other than FDX and its subsidiaries, that we estimate will comprise 5% or more of our total Rental and Reimbursement Revenue for fiscal 2022 are subsidiaries of Amazon, which is estimated to be 6% of our Annualized Rental and Reimbursement Revenue for fiscal 2022 and was 6% for of our Annualized Rental and Reimbursement Revenue for fiscal 2021
Percentage of aggregate rental and reimbursement revenue					57.00%	57.00%
Fdx [Member] \| Rental and Reimbursement Revenue [Member]
Real Estate [Line Items]
Percentage of aggregate rental and reimbursement revenue					4.00%	5.00%
Fdx Subsidiaries [Member] \| Rental and Reimbursement Revenue [Member]
Real Estate [Line Items]
Percentage of aggregate rental and reimbursement revenue					53.00%	52.00%