| Document and Entity Information | Sep. 01, 2021 |
| Document And Entity Information [Line Items] | |
| Entity Registrant Name | HANCOCK WHITNEY CORPORATION |
| Document Type | 8-K |
| Amendment Flag | false |
| Entity Central Index Key | 0000750577 |
| Document Period End Date | Sep. 1, 2021 |
| Entity Emerging Growth Company | false |
| Entity File Number | 001-36872 |
| Entity Incorporation, State 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 |
| Common Stock, $3.33 Par Value [Member] | |
| Document And Entity Information [Line Items] | |
| Security 12b Title | COMMON STOCK, $3.33 PAR VALUE |
| Trading Symbol | HWC |
| Security Exchange Name | NASDAQ |
| 6.25% Subordinated Notes [Member] | |
| Document And Entity Information [Line Items] | |
| Security 12b Title | 6.25% SUBORDINATED NOTES |
| Trading Symbol | HWCPZ |
| Security Exchange Name | NASDAQ |
