Line of Credit Facility, Available Additional Borrowing Capacity

No definition available.

Name:	oii_LineOfCreditFacilityAvailableAdditionalBorrowingCapacity
Namespace Prefix:	oii_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Line of Credit Facility, Basis Spread on Variable Rate

+ References

No definition available.

+ Details

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Namespace Prefix:	oii_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

oii term loan facility spread on variable rate

+ References

No definition available.

+ Details

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Namespace Prefix:	oii_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- 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

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

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.19(b),22(b))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 22

-Article 5

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The cash outflow for loan and debt issuance costs.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 15

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3291-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

-URI http://asc.fasb.org/extlink&oid=6513228

+ Details

Name:	us-gaap_PaymentsOfFinancingCosts
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=oii_CreditAgreementMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	oii_AdvanceTypeAxis=oii_AdjustedBaseRateAdvancesMember
Namespace Prefix:
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Balance Type:
Period Type:

- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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Debt - Line of Credit (Details) - USD ($) $ in Millions	12 Months Ended
Debt - Line of Credit (Details) - USD ($) $ in Millions	Dec. 31, 2014	Jun. 30, 2015	Oct. 27, 2014
Line of Credit Facility [Line Items]
Line of Credit Facility, Available Additional Borrowing Capacity		$ 300.0
Payments of Financing Costs	$ 1.6
Line of Credit [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity			$ 500.0
Credit Agreement [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity			$ 300.0
Credit Agreement [Member] \| Adjusted Base Rate Advances [Member] \| Adjusted Base Rate [Member] \| Federal Funds Rate [Member] \| Minimum [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Basis Spread on Variable Rate			0.50%
Credit Agreement [Member] \| Adjusted Base Rate Advances [Member] \| Adjusted Base Rate [Member] \| Eurodollar Rate [Member] \| Minimum [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Basis Spread on Variable Rate			1.00%
Credit Agreement [Member] \| Adjusted Base Rate Advances [Member] \| Applicable Margin [Member] \| Minimum [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Basis Spread on Variable Rate			0.125%
oii term loan facility spread on variable rate			0.00%
Credit Agreement [Member] \| Adjusted Base Rate Advances [Member] \| Applicable Margin [Member] \| Maximum [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Basis Spread on Variable Rate			0.75%
oii term loan facility spread on variable rate			0.50%
Credit Agreement [Member] \| Eurodollar Advances [Member] \| Applicable Margin [Member] \| Minimum [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Basis Spread on Variable Rate			1.125%
oii term loan facility spread on variable rate			1.00%
Credit Agreement [Member] \| Eurodollar Advances [Member] \| Applicable Margin [Member] \| Maximum [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Basis Spread on Variable Rate			1.75%
oii term loan facility spread on variable rate			1.50%