Line of Credit Facility, Available Additional Borrowing Capacity

No definition available.

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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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Data Type:	num:percentItemType
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Period Type:	instant

- Definition

The amount of cash paid for interest during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4297-108586

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 25
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3536-108585

+ Details

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Period Type:	duration

- 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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- 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

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The cash outflow paid to third parties in connection with debt origination, which will be amortized over the remaining maturity period of the associated long-term debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3291-108585

+ Details

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

- 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=66902209&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

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Balance Type:	credit
Period Type:	duration

- Details

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- Details

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- Details

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- Details

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Data Type:	na
Balance Type:
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- Details

Name:	oii_InterestRateComponentAxis=oii_AdjustedBaseRateMember
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Balance Type:
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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, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Jan. 25, 2023	Oct. 25, 2021	Oct. 27, 2014
Line of Credit Facility [Line Items]
Line of Credit Facility, Available Additional Borrowing Capacity	$ 300.0
Interest Paid	$ 32.4	$ 29.2	$ 27.2
Payments of Debt Issuance Costs				$ 6.9
Payments of Financing Costs				$ 2.6
Minimum [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage	0.125%
Maximum [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage	0.30%
Credit Agreement [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity					$ 450.0	$ 500.0	$ 500.0
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%
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%
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%
Letter of Credit [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%