Name:	op_VesselOperatingExpensesAbstract
Namespace Prefix:	op_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

Amount of operating expenses for vessel repair and maintenance, spares, stores, classification, chemicals and gases, paints and victualling.

No definition available.

Name:	op_VesselRepairAndMaintenanceExpenses
Namespace Prefix:	op_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

The expense in the period incurred with respect to protection provided by insurance entities against risks other than risks associated with production (which are allocated to cost of sales).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.4)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483621/220-10-S99-2

Name:	us-gaap_GeneralInsuranceExpense
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Amount of expense for salary, wage, profit sharing; incentive and equity-based compensation; and other employee benefit.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(b)(4))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483621/220-10-S99-2

Name:	us-gaap_LaborAndRelatedExpense
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Generally recurring costs associated with normal operations except for the portion of these expenses which can be clearly related to production and included in cost of sales or services. Excludes Selling, General and Administrative Expense.

No definition available.

Name:	us-gaap_OperatingCostsAndExpenses
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

The total amount of other operating cost and expense items that are associated with the entity's normal revenue producing operation.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04(7)(b))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483586/944-220-S99-1

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.3)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483621/220-10-S99-2

Name:	us-gaap_OtherCostAndExpenseOperating
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

All taxes not related to income of the entity or excise or sales taxes levied on the revenue of the entity that are not reported elsewhere. These taxes could include production, real estate, personal property, and pump tax.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(4))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483621/220-10-S99-2