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Amended and Restated Bylaws, Eligible Shareholders' Ownership Interest, Percent

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Amended and Restated Bylaws, Number of Eligible Director Nominees

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Amended and Restated Bylaws, Number of Eligible Director Nominees, Percent of Current Number on Board of Directors

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Amended and Restated Bylaws, Number of Eligible Shareholders

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Percentage investment held by members or limited partners of limited liability company (LLC) or limited partnership (LP).

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The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

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Amount of transactions with related party during the financial reporting period.

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Subsequent Events Subsequent Events (Details) $ in Millions		1 Months Ended
Subsequent Events Subsequent Events (Details) $ in Millions	Feb. 22, 2019 USD ($) shareholder director	Dec. 31, 2018	Feb. 21, 2019
Subsequent Event
Subsequent Event [Line Items]
Number of shareholders in eligible group \| shareholder	20
Minimum ownership percentage as eligible shareholder (percent)	3.00%
Eligible shareholder common stock holding period	3 years
Minimum number of directors that can be nominated by eligible shareholders \| director	2
Nominees as percentage of directors on current board (percent)	20.00%
Oasis Petroleum \| Bobcat DevCo
Subsequent Event [Line Items]
Ownership interest (percent)		75.00%
Oasis Midstream Partners, LP \| Bobcat DevCo
Subsequent Event [Line Items]
Limited partner interest in OMP (percent)		25.00%
Affiliated Entity \| 2019 Capital Expenditures Arrangement \| Subsequent Event
Subsequent Event [Line Items]
Estimate of reimbursable amounts from OMP \| $	$ 80
Minimum \| Oasis Petroleum \| Bobcat DevCo \| Subsequent Event
Subsequent Event [Line Items]
Ownership interest (percent)			64.00%
Maximum \| Oasis Petroleum \| Bobcat DevCo \| Subsequent Event
Subsequent Event [Line Items]
Ownership interest (percent)			66.00%