Nominal volume used to calculate payments on a derivative instrument.

No definition available.

Name:	us-gaap_DerivativeNonmonetaryNotionalAmountVolume
Namespace Prefix:	us-gaap_
Data Type:	num:volumeItemType
Balance Type:	na
Period Type:	duration

- Definition

Average fixed price related to the group of price risk swap derivatives.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	us-types:perUnitItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any 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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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- 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

+ Details

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

- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

+ Details

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Period Type:	duration

- Details

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Namespace Prefix:
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- Details

Name:	us-gaap_DerivativeInstrumentRiskAxis=oas_TwoThousandNineteenSwapsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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

- Details

Name:	us-gaap_DerivativeInstrumentRiskAxis=us-gaap_SwapMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Namespace Prefix:
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- Details

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Namespace Prefix:
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Subsequent Events (Details) bbl in Thousands	1 Months Ended
Subsequent Events (Details) bbl in Thousands	Apr. 30, 2017 $ / bbl bbl	Apr. 10, 2017 USD ($)	Mar. 31, 2017 USD ($) $ / bbl $ / MMBTU
Subsequent Event [Line Items]
Maximum borrowing base			$ 1,150,000,000
Subsequent Event [Member]
Subsequent Event [Line Items]
Maximum borrowing base		$ 1,600,000,000
Line of credit facility, current borrowing commitment		$ 1,150,000,000
2019 Swaps [Member]
Subsequent Event [Line Items]
Average swap price (in dollars per barrel) \| $ / bbl			53.88
Crude Oil [Member] \| Swap [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Average swap price (in dollars per barrel) \| $ / bbl	54.12
Crude Oil [Member] \| 2018 Swaps [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Total ntional amount of oil (in Bbls) \| bbl	668
Crude Oil [Member] \| 2019 Swaps [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Total ntional amount of oil (in Bbls) \| bbl	62
Natural Gas [Member] \| 2018 Swaps [Member]
Subsequent Event [Line Items]
Average swap price (in dollars per barrel) \| $ / MMBTU			3.00