XML 69 R58.htm IDEA: XBRL DOCUMENT v3.10.0.1

Commitments (Details)	Sep. 30, 2018 USD ($)
Building Located In Hauppauge New York
Commitments
Contractual obligation	$ 960,000

X

- Definition

Amount of contractual obligation, including but not limited to, long-term debt, capital lease obligations, operating lease obligations, purchase obligations, and other commitments.

+ References

No definition available.

+ Details

Name:	us-gaap_ContractualObligation
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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_OtherCommitmentsLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Details

Name:	srt_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis=olp_BuildingLocatedInHauppaugeNewYorkMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: