| Document and Entity Information | Mar. 28, 2022 |
| Cover [Abstract] | |
| Amendment Flag | false |
| Entity Central Index Key | 0001889658 |
| Document Type | 8-K |
| Document Period End Date | Mar. 28, 2022 |
| Entity Registrant Name | Magallanes, Inc. |
| Entity Incorporation State Country Code | DE |
| Entity Tax Identification Number | 87-0943087 |
| Entity Address, Address Line One | One AT&T Plaza |
| Entity Address, Address Line Two | 208 South Akard Street |
| Entity Address, City or Town | Dallas |
| Entity Address, State or Province | TX |
| Entity Address, Postal Zip Code | 75202 |
| City Area Code | (210) |
| Local Phone Number | 821-4105 |
| Written Communications | false |
| Soliciting Material | false |
| Pre Commencement Tender Offer | false |
| Pre Commencement Issuer Tender Offer | false |
| Entity Emerging Growth Company | false |
