v3.25.2
Cover - shares
 6 Months Ended
Jun. 30, 2025
Jul. 28, 2025
Entity Information [Line Items]    
Document Type 10-Q  
Document Quarterly Report true  
Document Period End Date Jun. 30, 2025  
Document Transition Report false  
Entity File Number 001-38083  
Entity Registrant Name Magnolia Oil & Gas Corp  
Entity Incorporation, State or Country Code DE  
Entity Tax Identification Number 81-5365682  
Entity Address, Address Line One Nine Greenway Plaza, Suite 1300  
Entity Address, City or Town Houston,  
Entity Address, State or Province TX  
Entity Address, Postal Zip Code 77046  
City Area Code 713  
Local Phone Number 842-9050  
Title of 12(b) Security Class A Common Stock, par value $0.0001  
Trading Symbol MGY  
Security Exchange Name NYSE  
Entity Current Reporting Status Yes  
Entity Interactive Data Current Yes  
Entity Filer Category Large Accelerated Filer  
Entity Small Business false  
Entity Emerging Growth Company false  
Entity Shell Company false  
Entity Central Index Key 0001698990  
Current Fiscal Year End Date --12-31  
Document Fiscal Year Focus 2025  
Document Fiscal Period Focus Q2  
Amendment Flag false  
Class A Common Stock    
Entity Information [Line Items]    
Entity Common Stock, Shares Outstanding   185,291,079
Class B Common Stock    
Entity Information [Line Items]    
Entity Common Stock, Shares Outstanding   5,523,479