REAL ESTATE INVESTMENTS, NET - Intangible Assets Amortization (Details) - USD ($)	9 Months Ended
Sep. 30, 2021	Dec. 31, 2020
Real Estate [Line Items]
October through December 2021	$ 476,456
2022	1,905,826
2023	815,228
2024	728,499
Net amount	$ 3,926,009	$ 5,127,788
Below-Market Lease Intangibles
Weighted-average remaining amortization period	9 years 3 months 18 days
Tenant Origination and Absorption Costs
Real Estate [Line Items]
October through December 2021	$ 792,583
2022	2,715,030
2023	1,838,120
2024	1,726,446
2025	1,344,132
2026	720,006
Thereafter	2,606,249
Net amount	$ 11,742,566
Below-Market Lease Intangibles
Weighted-average remaining amortization period	7 years 1 month 6 days
Above-Market Lease Intangibles
Real Estate [Line Items]
October through December 2021	$ 32,455
2022	129,823
2023	127,174
2024	122,543
2025	115,996
2026	78,557
Thereafter	116,927
Net amount	$ 723,475
Below-Market Lease Intangibles
Weighted-average remaining amortization period	6 years 7 months 6 days
Below-Market Lease Intangibles
Below-Market Lease Intangibles
October through December 2021	$ (363,041)
2022	(1,217,029)
2023	(921,169)
2024	(917,750)
2025	(917,750)
2026	(912,347)
Thereafter	(6,216,928)
Net amount	$ (11,466,014)
Weighted-average remaining amortization period	11 years 9 months 18 days

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Amount of amortization income for lease with finite life acquired as part of real property acquisition at below market lease rate expected to be recognized after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization income for lease with finite life acquired as part of real property acquisition at below market lease rate expected to be recognized in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization income for lease with finite life acquired as part of real property acquisition at below market lease rate expected to be recognized in remainder of current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization income for lease with finite life acquired as part of real property acquisition at below market lease rate expected to be recognized in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization income for lease with finite life acquired as part of real property acquisition at below market lease rate expected to be recognized in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization income for lease with finite life acquired as part of real property acquisition at below market lease rate expected to be recognized in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization income for lease with finite life acquired as part of real property acquisition at below market lease rate expected to be recognized in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount after amortization of leases acquired as part of a real property acquisition at below market lease rate with a finite life.

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Amount of amortization for asset, excluding financial asset and goodwill, lacking physical substance with finite life expected to be recognized after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in remainder of current fiscal year.

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=120154696&loc=d3e54445-107959

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Remaining amortization period of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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