XML 42 R76.htm IDEA: XBRL DOCUMENT
v3.20.1

COMMITMENTS AND CONTINGENCIES (Details) | 12 Months Ended
--- | ---
Dec. 31, 2019 USD ($) item | Dec. 31, 2018 USD ($) | Dec. 31, 2017 USD ($)
Commitments |  |  |
Lesee, annual operating lease payments | $ | $ 463,867 |  |
General and administrative expense |  |  |
Commitments |  |  |
Pension expense | $ | $ 304,000 | $ 295,000 | $ 275,000
Five-Year Lease |  |  |
Commitments |  |  |
Operating lease, number of renewal options | item | 4 |  |
Operating lease, renewal term | 5 years |  |
Seven-Month Lease |  |  |
Commitments |  |  |
Operating lease, number of renewal options | item | 1 |  |
Operating lease, renewal term | 7 months |  |

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 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=77888426&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 cash outflow from operating lease, excluding payments to bring another asset to condition and location necessary for its intended use. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 45 -Paragraph 5 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918643-209977 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (g)(1) -URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918686-209980 + Details
Name: | us-gaap_OperatingLeasePayments
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

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_OtherCommitmentsLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of cost (reversal of cost) for pension benefits. Excludes other postretirement benefits. + References No definition available. + Details
Name: | us-gaap_PensionExpense
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Details
Name: | us-gaap_IncomeStatementLocationAxis=us-gaap_GeneralAndAdministrativeExpenseMember
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: |