| Document And Entity Information | Dec. 17, 2019 |
| Cover [Abstract] | |
| Entity Registrant Name | WORTHINGTON INDUSTRIES INC |
| Document Type | 8-K |
| Amendment Flag | false |
| Document Period End Date | Dec. 17, 2019 |
| Entity Central Index Key | 0000108516 |
| Entity Emerging Growth Company | false |
| Entity File Number | 1-8399 |
| Entity Incorporation, State or Country Code | OH |
| Entity Tax Identification Number | 31-1189815 |
| Entity Address, Address Line One | 200 Old Wilson Bridge Road |
| Entity Address, City or Town | Columbus |
| Entity Address, State or Province | OH |
| Entity Address, Postal Zip Code | 43085 |
| City Area Code | 614 |
| Local Phone Number | 438-3210 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Title of each class | Common Shares, without par value |
| Trading Symbol | WOR |
| Name of each exchange on which registered | NYSE |
