XML 60 R45.htm IDEA: XBRL DOCUMENT v3.7.0.1

VARIABLE INTEREST ENTITIES, CONTINGENT LIABILITIES AND CONSOLIDATED JOINT VENTURES - Consolidated Joint Ventures (Details)	12 Months Ended
	Dec. 31, 2016 USD ($) item	Jun. 30, 2014
Consolidated JV
Variable Interest Entities
Number of joint ventures with controlling interest | item	5
Industrial building, Joppa, Maryland
Variable Interest Entities
Ownership interest in consolidated joint venture of the company (as a percent)		95.00%
Preferred interest | $	$ 6,280,000
Accrued interest | $	$ 455,000
Consolidated VIE entities | Consolidated JV
Variable Interest Entities
Number of joint ventures with controlling interest | item	6
Minimum | Consolidated JV
Variable Interest Entities
Ownership interest in consolidated joint venture of the company (as a percent)	85.00%
Maximum | Consolidated JV
Variable Interest Entities
Ownership interest in consolidated joint venture of the company (as a percent)	95.00%

X

- Definition

Represents the amount of accrued interest included in the preferred interest.

+ References

No definition available.

+ Details

Name:	olp_AccruedInterestOfPreferredInterestInJointVenture
Namespace Prefix:	olp_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

X

- Definition

Represents the number of joint ventures in which entity has controlling interest.

+ References

No definition available.

+ Details

Name:	olp_NumberOfControllingInterestJointVentures
Namespace Prefix:	olp_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Represents the amount of repayment made towards the preferred interest, out of the mortgage proceeds received by the company.

+ References

No definition available.

+ Details

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

X

- Definition

The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

+ References

No definition available.

+ Details

Name:	us-gaap_MinorityInterestOwnershipPercentageByParent
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
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_VariableInterestEntityLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Details

Name:	us-gaap_InvestmentsInAndAdvancesToAffiliatesCategorizationAxis=olp_ConsolidatedJointVentureMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_VariableInterestEntitiesByClassificationOfEntityAxis=olp_IndustrialBuildingJoppaMarylandMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_VariableInterestEntitiesByClassificationOfEntityAxis=olp_ConsolidatedVieEntitiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_RangeAxis=us-gaap_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_RangeAxis=us-gaap_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: