The amount of adjustment to gain on sale of properties attributable to write-off of unearned rental income.

No definition available.

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- Definition

Number of properties sold.

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

The amount of reduction to gain on sale of properties attributable to write-off of lease incentives and tenant-related receivable, offset by write-off of unearned rental income.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

The amount of reduction to gain on sale of properties attributable to write-off of lease incentives.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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Period Type:	duration

- Definition

The amount of reduction to gain on sale of properties attributable to write-off of tenant-related receivable.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of contracted sale price for property held-for-sale.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Represents the amount of unbilled rent receivable written off during the period relating to properties sold.

+ References

No definition available.

+ Details

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Namespace Prefix:	olp_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (c)
-URI https://asc.fasb.org/extlink&oid=109226691&loc=d3e2941-110230

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=126954810&loc=d3e3602-108585

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 45
-Paragraph 5
-URI https://asc.fasb.org/extlink&oid=126905981&loc=d3e2443-110228

+ Details

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- Definition

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.

+ References

No definition available.

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents properties which were acquired directly or through foreclosure for which a committed plan to sell exists and an active program to market such properties has been initiated.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

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- Details

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- Details

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- Details

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- Details

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SALES OF PROPERTIES AND PROPERTY HELD-FOR-SALE (Details)		1 Months Ended	3 Months Ended		6 Months Ended
	Feb. 28, 2023 USD ($)	Mar. 31, 2022 USD ($) property	Jun. 30, 2023 USD ($)	Mar. 31, 2022 USD ($)	Jun. 30, 2023 USD ($)	Mar. 31, 2023 USD ($)	Aug. 31, 2022 USD ($)
SALES OF PROPERTIES
Property held-for-sale						$ 2,783,000
Properties disposed of by sale \| Restaurant property located in Hauppauge, New York
SALES OF PROPERTIES
Proceeds from sale of real estate, net of closing costs	$ 4,076,000
Gain on sale of real estate, net	1,534,000
Reduction to Gain on sale of real estate, net, attributable to write-off of lease incentive and tenant-related receivable, offset by write-off of unearned rental income	128,000
Reduction to Gain on sale of real estate, net, attributable to write-off of lease incentive	85,000
Reduction to Gain on sale of real estate, net, attributable to write-off of tenant-related receivable	86,000
Adjustment to Gain on sale of real estate, net, attributable to write-off of unearned rental income	$ 43,000
Properties disposed of by sale \| Four restaurant properties located in Pennsylvania
SALES OF PROPERTIES
Number of properties sold \| property		4
Proceeds from sale of real estate, net of closing costs		$ 9,555,000
Gain on sale of real estate, net				$ 4,649,000
Write-off of unbilled rent receivable, as a reduction to Gain on sale of real estate, net		$ 512,000
Properties held-for-sale \| Retail property located in Duluth, Georgia
SALES OF PROPERTIES
Contracted sale price of property							$ 6,000,000
Property held-for-sale						$ 2,783,000
Properties held-for-sale \| Retail property located in Duluth, Georgia \| Forecast
SALES OF PROPERTIES
Gain on sale of real estate, net			$ 3,100,000		$ 3,100,000