| Cover | Nov. 21, 2019 |
| Cover Page [Abstract] | |
| Document Type | 8-K |
| Document Period End Date | Nov. 21, 2019 |
| Entity Registrant Name | UNITEDHEALTH GROUP INCORPORATED |
| Entity Incorporation, State or Country Code | DE |
| Entity File Number | 1-10864 |
| Entity Tax Identification Number | 41-1321939 |
| Entity Address, Address Line One | UnitedHealth Group Center, 9900 Bren Road East, |
| Entity Address, City or Town | Minnetonka, |
| Entity Address, State or Province | MN |
| Entity Address, Postal Zip Code | 55343 |
| City Area Code | 952 |
| Local Phone Number | 936-1300 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Title of 12(b) Security | Common Stock, $.01 par value |
| Trading Symbol | UNH |
| Security Exchange Name | NYSE |
| Entity Emerging Growth Company | false |
| Cover Non-Printing | Nov. 21, 2019 |
| Cover Page [Abstract] | |
| Entity Central Index Key | 0000731766 |
| Amendment Flag | false |
