v3.26.1
Cover - shares
shares in Thousands
 6 Months Ended
Jun. 30, 2026
Jul. 31, 2026
Document Information [Line Items]    
Document Type 10-Q  
Document Quarterly Report true  
Document Period End Date Jun. 30, 2026  
Document Transition Report false  
Entity File Number 001-40154  
Entity Registrant Name Oscar Health, Inc.  
Entity Incorporation, State or Country Code DE  
Entity Tax Identification Number 46-1315570  
Entity Address, Address Line One 75 Varick Street, 5th Floor,  
Entity Address, City or Town New York,  
Entity Address, State or Province NY  
Entity Address, Postal Zip Code 10013  
City Area Code (646)  
Local Phone Number 403-3677  
Title of 12(b) Security Class A Common Stock, $0.00001 par value per share  
Trading Symbol OSCR  
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  
Document Fiscal Year Focus 2026  
Document Fiscal Period Focus Q2  
Amendment Flag false  
Current Fiscal Year End Date --12-31  
Entity Central Index Key 0001568651  
Common Class A    
Document Information [Line Items]    
Entity Common Stock, Shares Outstanding   273,469
Common Class B    
Document Information [Line Items]    
Entity Common Stock, Shares Outstanding   35,176