Long-Term Incentive Compensation - Narrative (Details) - USD ($)	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Deferred compensation arrangement, recorded liability	$ 2,000,000.0	$ 1,400,000
Stock-based compensation expense	1,200,000	4,400,000
Share-based compensation costs not yet recognized	15,600,000
Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Deferred compensation arrangement, potential maximum liability	0	0
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Deferred compensation arrangement, potential maximum liability	$ 4,000,000.0	$ 2,700,000
Service-based Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)	3 years
Performance-based Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance period (in years)	3 years
Percentage of additional performance-based awards issued (in shares)	200.00%

Deferred Compensation Arrangement with Individual, Potential Maximum Liability

No definition available.

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Namespace Prefix:	ois_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Represents the maximum percentage of target award that might be granted as additional shares.

+ References

No definition available.

+ Details

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Performance Period

+ References

No definition available.

+ Details

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- Definition

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5047-113901

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.F)
-URI http://asc.fasb.org/extlink&oid=115993241&loc=d3e301413-122809

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

+ Details

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Balance Type:	debit
Period Type:	duration

- Definition

The carrying amount of the liability as of the balance sheet date to an individual under a deferred compensation arrangement. This amount may be the result of periodic accruals made over the period of active employment, or reflect termination benefits resulting contractual terms or a death benefit.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 710
-SubTopic 10
-Section 30
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6409875&loc=d3e20015-108363

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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- Definition

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

+ Details

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- 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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