| Cover page Document | Feb. 10, 2021 |
| Cover [Abstract] | |
| Document Type | 8-K |
| Document Period End Date | Feb. 10, 2021 |
| Entity Registrant Name | Altice USA, Inc. |
| Entity Incorporation, State or Country Code | DE |
| Entity File Number | 001-38126 |
| Entity Tax Identification Number | 38-3980194 |
| Entity Address, Address Line One | 1 Court Square West |
| Entity Address, City or Town | Long Island City, |
| Entity Address, State or Province | NY |
| Entity Address, Postal Zip Code | 11101 |
| City Area Code | 516 |
| Local Phone Number | 803-2300 |
| 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, par value $0.01 per share |
| Trading Symbol | ATUS |
| Security Exchange Name | NYSE |
| Entity Central Index Key | 0001702780 |
| Amendment Flag | false |
| Entity Emerging Growth Company | false |
