| Document and Entity Information | Mar. 09, 2020 |
| Cover [Abstract] | |
| Document Type | 8-K |
| Amendment Flag | false |
| Document Period End Date | Mar. 9, 2020 |
| Entity Registrant Name | Thor Industries, Inc. |
| Entity Central Index Key | 0000730263 |
| Entity Emerging Growth Company | false |
| Entity File Number | 1-9235 |
| Entity Incorporation, State or Country Code | DE |
| Entity Tax Identification Number | 93-0768752 |
| Entity Address, Address Line One | 601 East Beardsley Avenue |
| Entity Address, City or Town | Elkhart |
| Entity Address, State or Province | IN |
| Entity Address, Postal Zip Code | 46514-3305 |
| City Area Code | (574) |
| Local Phone Number | 970-7460 |
| Written Communications | false |
| Soliciting Material | false |
| Pre Commencement Tender Offer | false |
| Pre Commencement Issuer Tender Offer | false |
| Security 12b Title | Common Stock (Par value $.10 Per Share) |
| Trading Symbol | THO |
| Security Exchange Name | NYSE |
