| N-2 | Mar. 31, 2023 |
| Cover [Abstract] | |
| Entity Central Index Key | 0001258623 |
| Amendment Flag | true |
| Amendment Description | This Post-Effective Amendment No. 1 to the Registration Statement on Form N-2 (File No. 333-266343) of Eaton Vance Senior Floating-Rate Trust (the “Registration Statement”) is being filed pursuant to Rule 462(d) under the Securities Act of 1933, as amended (the “Securities Act”), solely for the purpose of filing exhibits to the Registration Statement. Accordingly, this Post-Effective Amendment No. 1 consists only of a facing page, this explanatory note and Part C of the Registration Statement on Form N-2 setting forth the exhibits to the Registration Statement. This Post-Effective Amendment No. 1 does not modify any other part of the Registration Statement. Pursuant to Rule 462(d) under the Securities Act, this Post-Effective Amendment No. 1 shall become effective immediately upon filing with the Securities and Exchange Commission. The contents of the Registration Statement are hereby incorporated by reference. |
| Document Type | POS EX |
| Entity Registrant Name | EATON VANCE SENIOR FLOATING RATE TRUST |
| Entity Address, Address Line One | Two International Place |
| Entity Address, City or Town | Boston |
| Entity Address, State or Province | MA |
| Entity Address, Postal Zip Code | 02110 |
| City Area Code | (617) |
| Local Phone Number | 482-8260 |
| No Substantive Changes, 462(c) | false |
| Exhibits Only, 462(d) | true |
| Entity Well-known Seasoned Issuer | No |
| Entity Emerging Growth Company | false |
| Business Contact [Member] | |
| Cover [Abstract] | |
| Entity Address, Address Line One | Two International Place |
| Entity Address, City or Town | Boston |
| Entity Address, State or Province | MA |
| Entity Address, Postal Zip Code | 02110 |
| Contact Personnel Name | Deidre E. Walsh |
