Long-Term Debt - Schedule of Long-Term Debt (Details) - USD ($)	Mar. 31, 2021	Mar. 30, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Total OMP long-term debt	$ 674,238,000		$ 450,000,000
Total long-term debt	674,238,000		710,000,000
Senior Notes \| OMP Senior Notes
Debt Instrument [Line Items]
Total OMP long-term debt	450,000,000	$ 450,000,000.0	0
Less: unamortized deferred financing costs on OMP Senior Notes	(9,762,000)		0
Revolving Credit Facility \| Credit Facility \| Oasis Credit Facility
Debt Instrument [Line Items]
Total OMP long-term debt	0		260,000,000
Revolving Credit Facility \| Credit Facility \| OMP Credit Facility
Debt Instrument [Line Items]
Total OMP long-term debt	234,000,000		$ 450,000,000
Total long-term debt	$ 234,000,000.0

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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