| Document and Entity Information | Apr. 28, 2021 |
| Document And Entity Information [Line Items] | |
| Entity Registrant Name | HANCOCK WHITNEY CORP |
| Amendment Flag | false |
| Entity Central Index Key | 0000750577 |
| Document Type | 8-K |
| Document Period End Date | Apr. 28, 2021 |
| Entity Incorporation State Country Code | MS |
| Entity File Number | 001-36872 |
| Entity Tax Identification Number | 64-0693170 |
| Entity Address, Address Line One | One Hancock 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 |
| Entity Emerging Growth Company | false |
| Common Stock Dollar Three Point Thirty Three Par Value [Member] | |
| Document And Entity Information [Line Items] | |
| Security 12b Title | Common stock, par value $3.33 per share |
| Trading Symbol | HWC |
| Security Exchange Name | NASDAQ |
| Six Point Twenty Five Percentage Subordinated Notes [Member] | |
| Document And Entity Information [Line Items] | |
| Security 12b Title | 6.25% Subordinated Notes |
| Trading Symbol | HWCPZ |
| Security Exchange Name | NASDAQ |
| Five Point Ninety Five Percentage Subordinated Notes [Member] | |
| Document And Entity Information [Line Items] | |
| Security 12b Title | 5.95% Subordinated Notes |
| Trading Symbol | HWCPL |
| Security Exchange Name | NASDAQ |
