| Document and Entity Information | May 04, 2021 |
| Cover [Abstract] | |
| Document Type | 8-K |
| Document Period End Date | May 4, 2021 |
| Entity Registrant Name | Lancaster Colony Corporation |
| Entity Incorporation, State or Country Code | OH |
| Entity File Number | 000-04065 |
| Entity Tax Identification Number | 13-1955943 |
| Entity Address, Address Line One | 380 Polaris Parkway |
| Entity Address, Address Line Two | Suite 400 |
| Entity Address, City or Town | Westerville |
| Entity Address, State or Province | OH |
| Entity Address, Postal Zip Code | 43082 |
| City Area Code | (614) |
| Local Phone Number | 224-7141 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Title of 12(b) Security | Common Stock, without par value |
| Trading Symbol | LANC |
| Security Exchange Name | NASDAQ |
| Entity Emerging Growth Company | false |
| Entity Central Index Key | 0000057515 |
| Amendment Flag | false |
