Long-Term Incentive Plans - Summary of Non-vested Restricted Stock Unit Award Activity (Detail) - $ / shares	1 Months Ended	2 Months Ended	6 Months Ended
Aug. 05, 2019	Sep. 30, 2019	Jun. 30, 2019
Units
Vested, Number of Units	(38,181)	(602,053)	(412,938)
Restricted Stock Units (RSUs) [Member] \| Midstates 2016 Long Term Incentive Plan [Member]
Units
Outstanding, Number of Units, Beginning Balance		353,464
Granted, Number of Units		0
Forfeited, Number of units		0
Vested, Number of Units		(327,802)
Outstanding, Number of Units, Ending Balance	353,464	25,662
Outstanding, Weighted-Average Grant Date Fair Value per unit, Beginning balance		$ 12.25
Granted, Weighted-Average Grant Date Fair Value per Unit		0
Forfeited, Weighted-Average Grant Date Fair Value per Unit		0
Vested, Weighted-Average Grant Date Fair Value per Unit		12.02
Outstanding, Weighted-Average Grant Date Fair Value per unit, Ending balance	$ 12.25	$ 15.23

The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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 (c)(1)(iv)(3)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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- Definition

Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(3)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

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-Publisher FASB
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-Topic 718
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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-Paragraph 2
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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

+ References

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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