The parent entity's controlling interest held in a consolidated entity, expressed as a percentage.

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Gross proceeds received from the sale of real estate during the current period.

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Represents the unamortized amount of fixed rent on operating lease rent receivable over the term of lease.

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The amount of interest expense attributable to prepayment costs on debt related to interest rate swap termination.

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Income (loss) from sale of consolidated JV property attributable to noncontrolling interest.

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Proceeds, net of closing costs received from the sale of real estate during the current period.

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Amount of deferred income excluding obligation to transfer product and service to customer for which consideration has been received or is receivable.

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The difference between the carrying value and the sale price of real estate or properties that were intended to be sold or held for capital appreciation or rental income. This element refers to the gain (loss) included in earnings and not to the cash proceeds of the sale. This element is a noncash adjustment to net income when calculating net cash generated by operating activities using the indirect method.

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The charge against earnings in the period to reduce the carrying amount of real property to fair value.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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Amount of cash outflow for cost from early extinguishment and prepayment of debt. Includes, but is not limited to, third-party cost, premium paid, and other fee paid to lender directly for debt extinguishment or debt prepayment. Excludes accrued interest.

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Amount of real estate investment property, net of accumulated depreciation, which may include the following: (1) land available-for-sale; (2) land available-for-development; (3) investments in building and building improvements; (4) tenant allowances; (5) developments in-process; (6) rental properties; and (7) other real estate investments.

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The cash outflow to repay long-term debt that is wholly or partially secured by collateral. Excludes repayments of tax exempt secured debt.

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SALES OF PROPERTIES (Details) - USD ($)								3 Months Ended	12 Months Ended
SALES OF PROPERTIES (Details) - USD ($)	Feb. 11, 2020	Dec. 10, 2019	Aug. 23, 2019	Jun. 20, 2019	Jan. 30, 2018	Nov. 14, 2017	Jul. 14, 2017	Mar. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Sep. 14, 2018	Nov. 30, 2017
Sale of Property
Gross Sales Price									$ 41,891,000	$ 27,659,000	$ 27,050,000
Real estate investments, net									700,535,000	705,459,000
Gain (Loss) on Sale of Real Estate, Net									4,327,000	5,262,000	9,837,000
Impairment loss											153,000
Mortgage paid off									19,970,000	24,502,000	12,936,000
Kmart retail property, Clemmons, North Carolina
Sale of Property
Gross Sales Price									5,500,000
Gain (Loss) on Sale of Real Estate, Net									1,099,000
Multi-tenant retail property, Athens, Georgia
Sale of Property
Gross Sales Price									6,050,000
Gain (Loss) on Sale of Real Estate, Net									1,045,000
Prepayment costs on debt related to a swap termination fee			$ 161,000
Land - The Briarbrook Village Apartments, Wheaton, Illinois
Sale of Property
Gross Sales Price									12,066,000
Gain (Loss) on Sale of Real Estate, Net									1,530,000
Aaron's retail property, Houston, Texas
Sale of Property
Gross Sales Price									1,675,000
Gain (Loss) on Sale of Real Estate, Net									218,000
Assisted living facility, Round Rock, Texas
Sale of Property
Gross Sales Price									16,600,000
Gain (Loss) on Sale of Real Estate, Net									$ 435,000
Prepayment costs on debt related to a swap termination fee		$ 625,000
Multi-tenant retail property, Fort Bend, Texas
Sale of Property
Gross Sales Price										9,200,000
Gain (Loss) on Sale of Real Estate, Net										2,408,000
Land - The Meadows Apartments, Lakemoor, Illinois
Sale of Property
Gross Sales Price										8,459,000
Gain (Loss) on Sale of Real Estate, Net										4,585,000
Unamortized balance, fixed rent												$ 5,717,000
Deferred income													$ 5,906,000
Shopko retail property, Lincoln, Nebraska
Sale of Property
Gross Sales Price										10,000,000
Gain (Loss) on Sale of Real Estate, Net										$ (1,731,000)
Former Sports Authority retail property, Greenwood Village, Colorado
Sale of Property
Gross Sales Price											9,500,000
Gain (Loss) on Sale of Real Estate, Net											6,568,000
Kohl's retail property, Kansas City, Missouri
Sale of Property
Gross Sales Price											10,250,000
Gain (Loss) on Sale of Real Estate, Net											2,180,000
Prepayment costs on debt related to a swap termination fee							$ 131,000
Former hhgregg retail property, Niles, Illinois
Sale of Property
Gross Sales Price											5,000,000
Gain (Loss) on Sale of Real Estate, Net											1,089,000
Joe's Crab Shack restaurant property, Ann Arbor, Michigan
Sale of Property
Gross Sales Price											$ 2,300,000
Impairment loss						$ 153,000
Prepayment costs on debt related to a swap termination fee						$ 70,000
Retail property, Onalaska, Wisconsin
Sale of Property
Gain (Loss) on Sale of Real Estate, Net								$ 4,250,000
Proceeds from sale of real estate, net of closing costs	$ 7,093,000
Repayment of debt cost	290,000
Mortgage paid off	$ 3,332,000
Retail property, Onalaska, Wisconsin \| Rental income, net \| Geographic concentration
Sale of Property
Concentration risk percentage									1.00%	1.00%	1.00%
Consolidated Joint Venture \| Kmart retail property, Clemmons, North Carolina
Sale of Property
Ownership interest in consolidated joint venture of the company (as a percent)				90.00%
Prepayment costs on debt related to a swap termination fee				$ 41,000
Non-controlling interest's share of the gain				$ 422,000
Consolidated Joint Venture \| Multi-tenant retail property, Fort Bend, Texas
Sale of Property
Ownership interest in consolidated joint venture of the company (as a percent)					85.00%
Non-controlling interest's share of the gain					$ 776,000