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SALES OF PROPERTIES, PROPERTIES HELD-FOR-SALE AND IMPAIRMENT LOSS (Details) - USD ($)																				3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 25, 2025	Sep. 08, 2025	Aug. 01, 2025	Jul. 15, 2025	Jun. 27, 2025	Jun. 25, 2025	Jun. 23, 2025	Jan. 21, 2025	Jan. 16, 2025	Sep. 16, 2024	Aug. 29, 2024	Aug. 15, 2024	Jun. 28, 2024	Jun. 10, 2024	Jun. 07, 2024	Jun. 06, 2024	May 09, 2024	May 06, 2024	Mar. 06, 2024	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024	Dec. 31, 2025	Sep. 09, 2025
SALES OF PROPERTIES AND IMPAIRMENT LOSS
(Loss) Gain on Sale of Real Estate, Net																				$ 9,071,000	$ 2,115,000	$ 16,712,000	$ 11,347,000
Impairment loss																				1,300,000		1,300,000	1,086,000
Vacant health and fitness property in Hamilton, Ohio
SALES OF PROPERTIES AND IMPAIRMENT LOSS
Impairment loss																							1,086,000
Retail property located in Port Clinton, Ohio \| Forecast
SALES OF PROPERTIES AND IMPAIRMENT LOSS
Estimated Gain on Sale of Real Estate Net																								$ 200,000
The Vue Apartments, Beachwood, Ohio
SALES OF PROPERTIES AND IMPAIRMENT LOSS
Impairment loss																				1,300,000		1,300,000
Properties disposed of by sale
SALES OF PROPERTIES AND IMPAIRMENT LOSS
Gross Sales Price																						49,461,000	39,445,000
(Loss) Gain on Sale of Real Estate, Net																						16,712,000	11,347,000
Mortgage prepaid on sale of real estate																						6,773,000	10,714,000
Reduction to Gain on sale of real estate, net, attributable to the write-off of unbilled rent receivable																						1,125,000	285,000
Reduction to Gain on sale of real estate, net, attributable to the write-off of net unamortized lease assets and liabilities																						67,000	64,000
Reduction to Gain on sale of real estate, net, attributable to the write-off of other assets and receivables																						703,000	108,000
Properties disposed of by sale \| Land and improvements in Lakewood, Colorado
SALES OF PROPERTIES AND IMPAIRMENT LOSS
Gross Sales Price									$ 400,000
(Loss) Gain on Sale of Real Estate, Net									(44,000)
Non-controlling interest's share of the gain									$ (4,000)
Properties disposed of by sale \| Hooters restaurant property in Concord, North Carolina
SALES OF PROPERTIES AND IMPAIRMENT LOSS
Gross Sales Price								$ 3,253,000
(Loss) Gain on Sale of Real Estate, Net								$ 1,154,000
Properties disposed of by sale \| Multi-tenant retail stores, Lakewood, Colorado
SALES OF PROPERTIES AND IMPAIRMENT LOSS
Gross Sales Price							$ 17,900,000
(Loss) Gain on Sale of Real Estate, Net							3,276,000
Properties disposed of by sale \| Total Wine retail property, Greensboro, North Carolina
SALES OF PROPERTIES AND IMPAIRMENT LOSS
Gross Sales Price						$ 4,709,000
(Loss) Gain on Sale of Real Estate, Net						$ 2,232,000
Properties disposed of by sale \| LaZBoy retail property, Gurnee, Illinois
SALES OF PROPERTIES AND IMPAIRMENT LOSS
Gross Sales Price					$ 4,368,000
(Loss) Gain on Sale of Real Estate, Net					$ 1,023,000
Properties disposed of by sale \| Land parcel in Lakewood, Colorado
SALES OF PROPERTIES AND IMPAIRMENT LOSS
Gross Sales Price				$ 3,457,000
(Loss) Gain on Sale of Real Estate, Net				2,849,000
Non-controlling interest's share of the gain (loss)				$ 641,000
Properties disposed of by sale \| Office Depot retail property, Eugene, Oregon
SALES OF PROPERTIES AND IMPAIRMENT LOSS
Gross Sales Price			$ 6,000,000
(Loss) Gain on Sale of Real Estate, Net			$ 2,497,000
Properties disposed of by sale \| Blue Pearl Veterinary Hospital, Newark, Delaware
SALES OF PROPERTIES AND IMPAIRMENT LOSS
Gross Sales Price		$ 6,774,000
(Loss) Gain on Sale of Real Estate, Net		$ 3,236,000
Properties disposed of by sale \| Vacant retail property, Bolingbrook, Illinois
SALES OF PROPERTIES AND IMPAIRMENT LOSS
Gross Sales Price	$ 2,600,000
(Loss) Gain on Sale of Real Estate, Net	$ 489,000
Properties disposed of by sale \| Hacienda Colorado restaurant parcel in Lakewood, Colorado
SALES OF PROPERTIES AND IMPAIRMENT LOSS
Gross Sales Price																			$ 2,900,000
(Loss) Gain on Sale of Real Estate, Net																			1,784,000
Non-controlling interest's share of the gain																			$ 178,000
Properties disposed of by sale \| Applebee's restaurant property in Kennesaw, Georgia
SALES OF PROPERTIES AND IMPAIRMENT LOSS
Gross Sales Price																		$ 2,834,000
(Loss) Gain on Sale of Real Estate, Net																		$ 964,000
Properties disposed of by sale \| FedEx industrial property in Miamisburg, Ohio
SALES OF PROPERTIES AND IMPAIRMENT LOSS
Gross Sales Price																	$ 2,793,000
(Loss) Gain on Sale of Real Estate, Net																	$ 1,507,000
Properties disposed of by sale \| Havertys retail property in Wichita, Kansas
SALES OF PROPERTIES AND IMPAIRMENT LOSS
Gross Sales Price																$ 6,600,000
(Loss) Gain on Sale of Real Estate, Net																$ 1,884,000
Properties disposed of by sale \| Urban Outfitters retail property in Lawrence, Kansas
SALES OF PROPERTIES AND IMPAIRMENT LOSS
Gross Sales Price															$ 1,300,000
(Loss) Gain on Sale of Real Estate, Net															$ 43,000
Properties disposed of by sale \| Walgreens retail property in Cape Girardeau, Missouri
SALES OF PROPERTIES AND IMPAIRMENT LOSS
Gross Sales Price														$ 2,793,000
(Loss) Gain on Sale of Real Estate, Net														978,000
Non-controlling interest's share of the gain														$ 105,000
Properties disposed of by sale \| Vacant retail property in Kennesaw, Georgia
SALES OF PROPERTIES AND IMPAIRMENT LOSS
Gross Sales Price													$ 6,700,000
(Loss) Gain on Sale of Real Estate, Net													$ 2,072,000
Properties disposed of by sale \| Vacant health and fitness property in Hamilton, Ohio
SALES OF PROPERTIES AND IMPAIRMENT LOSS
Gross Sales Price												$ 4,350,000
(Loss) Gain on Sale of Real Estate, Net												$ 17,000
Impairment loss																							$ 1,086,000
Properties disposed of by sale \| Vacant industrial property in Wauconda, Illinois
SALES OF PROPERTIES AND IMPAIRMENT LOSS
Gross Sales Price											$ 4,425,000
(Loss) Gain on Sale of Real Estate, Net											$ 1,177,000
Properties disposed of by sale \| Hobby Lobby retail property in Woodbury, Minnesota
SALES OF PROPERTIES AND IMPAIRMENT LOSS
Gross Sales Price										$ 4,750,000
(Loss) Gain on Sale of Real Estate, Net										$ 921,000
Properties held-for-sale \| Retail property located in Port Clinton, Ohio
SALES OF PROPERTIES AND IMPAIRMENT LOSS
Contracted sale price of property																									$ 1,330,000
Net book value																				1,029,000		1,029,000
Properties held-for-sale \| The Vue Apartments, Beachwood, Ohio
SALES OF PROPERTIES AND IMPAIRMENT LOSS
Net book value																				16,200,000		16,200,000
Impairment loss																				$ 1,300,000		$ 1,300,000
Colorado JV \| Multi-tenant retail stores, Lakewood, Colorado
SALES OF PROPERTIES AND IMPAIRMENT LOSS
Non-controlling interest's share of the gain (loss)							$ 972,000
Colorado JV \| Properties disposed of by sale \| Land and improvements in Lakewood, Colorado
SALES OF PROPERTIES AND IMPAIRMENT LOSS
Ownership interest in consolidated joint venture of the company (as a percent)									90.00%
Consolidated VIE 2
SALES OF PROPERTIES AND IMPAIRMENT LOSS
Ownership interest in consolidated joint venture of the company (as a percent)																						95.00%
Consolidated VIE 2 \| Properties disposed of by sale \| Walgreens retail property in Cape Girardeau, Missouri
SALES OF PROPERTIES AND IMPAIRMENT LOSS
Ownership interest in consolidated joint venture of the company (as a percent)														95.00%