| Document and Entity Information | Dec. 10, 2020 |
| Cover [Abstract] | |
| Entity Registrant Name | TEJON RANCH CO |
| Amendment Flag | false |
| Entity Central Index Key | 0000096869 |
| Document Type | 8-K |
| Document Period End Date | Dec. 10, 2020 |
| Entity Incorporation State Country Code | DE |
| Entity File Number | 1-7183 |
| Entity Tax Identification Number | 77-0196136 |
| Entity Address, Address Line One | P. O. Box 1000 |
| Entity Address, City or Town | Lebec |
| Entity Address, State or Province | CA |
| Entity Address, Postal Zip Code | 93243 |
| City Area Code | 661 |
| Local Phone Number | 248-3000 |
| Written Communications | false |
| Soliciting Material | false |
| Pre Commencement Tender Offer | false |
| Pre Commencement Issuer Tender Offer | false |
| Security 12b Title | Common Stock |
| Trading Symbol | TRC |
| Security Exchange Name | NYSE |
| Entity Emerging Growth Company | false |
