XML 48 R36.htm IDEA: XBRL DOCUMENT
v3.21.1

LEASES - As Lessee - Ground Lease and Office Lease (Details) | 3 Months Ended
--- | ---
Mar. 31, 2021 USD ($) item | Mar. 31, 2020 USD ($)
Real Estate in Greensboro, NC |  |
Lessee Accounting |  |
Operating lease, option to extend | true |
Operating lease, remaining lease term | 13 years 10 months 24 days |
Operating lease expense | $ | $ 150,000 | $ 131,000
Real Estate in Greensboro, NC | Maximum |  |
Lessee Accounting |  |
Operating lease, number of renewal options | item | 4 |
Real Estate in Greensboro, NC | Five-Year Lease |  |
Lessee Accounting |  |
Operating lease, renewal term | 5 years |
Real Estate in Greensboro, NC | Seven-Month Lease |  |
Lessee Accounting |  |
Operating lease, number of renewal options | item | 1 |
Operating lease, renewal term | 7 months |
Corporate office lease in Great Neck, NY |  |
Lessee Accounting |  |
Operating lease, option to extend | true |
Operating lease, remaining lease term | 15 years 9 months 18 days |
Operating lease expense | $ | $ 14,000 | $ 14,000
Corporate office lease in Great Neck, NY | Five-Year Lease |  |
Lessee Accounting |  |
Operating lease, renewal term | 5 years |

X
- Definition The number of renewal options available to the Company, as defined in the lease agreement. + References No definition available. + Details
Name: | olp_LesseeOperatingLeasesNumberOfRenewalOptions
Namespace Prefix: | olp_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- 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
Name: | us-gaap_LesseeLeaseDescriptionLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Indicates (true false) whether lessee has option to extend operating lease. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=121609121&loc=SL77918673-209980 + Details
Name: | us-gaap_LesseeOperatingLeaseExistenceOfOptionToExtend
Namespace Prefix: | us-gaap_
Data Type: | xbrli:booleanItemType
Balance Type: | na
Period Type: | duration

X
- Definition Remaining lease term of operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=121609121&loc=SL77918673-209980 + Details
Name: | us-gaap_LesseeOperatingLeaseRemainingLeaseTerm
Namespace Prefix: | us-gaap_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | instant

X
- Definition Term of lessee's operating lease renewal, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=121609121&loc=SL77918673-209980 + Details
Name: | us-gaap_LesseeOperatingLeaseRenewalTerm
Namespace Prefix: | us-gaap_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | instant

X
- Definition Amount of operating lease expense. Excludes sublease income. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 45 -Paragraph 4 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121603541&loc=SL77918638-209977 + Details
Name: | us-gaap_OperatingLeaseExpense
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Details
Name: | srt_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis=olp_GreensboroNCMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_MaximumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_TypeOfArrangementAxis=olp_FiveYearLeaseMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_TypeOfArrangementAxis=olp_SevenMonthLeaseMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis=olp_CorporateOfficeLeaseInGreatNeckMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |