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).

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- Definition

Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

+ References

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- Definition

The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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- Definition

The risk-free interest rate assumption that is used in valuing an option on its own shares.

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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.

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- Definition

Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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Equity-Based Compensation - Summary of Assumptions (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Performance share unit awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Forecast period			4 years
Risk-free interest rate (percent)			1.25%
Weighted average grant date fair value of awards granted (in dollars per share)	$ 12.71	$ 16.89	$ 3.00
Oasis stock price volatility		17.16%	59.38%
Fair value of awards vested	$ 5,300,000		$ 1,000,000
Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Oasis stock price volatility	72.88%
Phantom units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average grant date fair value of awards granted (in dollars per share)	$ 23.91
Minimum \| Performance share unit awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Forecast period	2 years	2 years
Minimum \| Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free interest rate (percent)	2.08%	1.18%
Maximum \| Performance share unit awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Forecast period	4 years	4 years
Maximum \| Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free interest rate (percent)	2.31%	1.66%
Oasis Midstream Partners, LP \| Phantom units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average grant date fair value of awards granted (in dollars per share)	$ 16.40	$ 16.40
Fair value of awards vested	$ 600,000	$ 0	$ 0