| Document And Entity Information | Sep. 09, 2020 |
| Cover [Abstract] | |
| Entity Registrant Name | HANCOCK WHITNEY CORP |
| Document Type | 8-K |
| Amendment Flag | false |
| Entity Central Index Key | 0000750577 |
| Document Period End Date | Sep. 9, 2020 |
| Entity Emerging Growth Company | false |
| Entity File Number | 001-36872 |
| Entity Incorporation, State or Country Code | MS |
| Entity Tax Identification Number | 64-0693170 |
| Entity Address, Address Line One | Hancock Whitney Plaza |
| Entity Address, Address Line Two | 2510 14th Street |
| Entity Address, City or Town | Gulfport |
| Entity Address, State or Province | MS |
| Entity Address, Postal Zip Code | 39501 |
| City Area Code | (228) |
| Local Phone Number | 868-4000 |
| 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 $3.33 per share |
| Trading Symbol | HWC |
| Name of each exchange on which registered | NASDAQ |
