| Cover Page | Nov. 07, 2023 |
| Cover [Abstract] | |
| Document Type | 8-K |
| Document Period End Date | Nov. 07, 2023 |
| Entity Registrant Name | Oscar Health, Inc. |
| Entity Incorporation, State or Country Code | DE |
| Entity File Number | 001-40154 |
| 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 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Title of 12(b) Security | Class A Common Stock, $0.00001 par value per share |
| Trading Symbol | OSCR |
| Security Exchange Name | NYSE |
| Entity Emerging Growth Company | false |
| Entity Central Index Key | 0001568651 |
| Amendment Flag | false |
