| Document And Entity Information | Oct. 01, 2020 |
| Cover [Abstract] | |
| Document Type | 8-K |
| Amendment Flag | false |
| Document Period End Date | Oct. 1, 2020 |
| Entity Registrant Name | ASHLAND GLOBAL HOLDINGS INC. |
| Entity Central Index Key | 0001674862 |
| Entity Emerging Growth Company | false |
| Entity File Number | 333-211719 |
| Entity Incorporation State or Country Code | DE |
| Entity Tax Identification Number | 81-2587835 |
| Entity Address Address Line1 | 8145 Blazer Drive |
| Entity Address City or Town | Wilmington |
| Entity Address State or Province | DE |
| Entity Address Postal Zip Code | 19808 |
| City Area Code | 302 |
| Local Phone Number | 995-3000 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Title of each class | Common Stock (par value $.01) |
| Trading Symbol | ASH |
| Name of each exchange on which registered | NYSE |
