| Document and Entity Information | Jan. 08, 2025 |
| Entity Listings [Line Items] | |
| Document Type | 8-K |
| Amendment Flag | false |
| Document Period End Date | Jan. 08, 2025 |
| Entity File Number | 001-05721 |
| Entity Registrant Name | JEFFERIES FINANCIAL GROUP INC. |
| Entity Central Index Key | 0000096223 |
| Entity Incorporation, State or Country Code | NY |
| Entity Tax Identification Number | 13-2615557 |
| Entity Address, Address Line One | 520 Madison Ave. |
| Entity Address, City or Town | New York |
| Entity Address, State or Province | NY |
| Entity Address, Postal Zip Code | 10022 |
| City Area Code | 212 |
| Local Phone Number | 284-2300 |
| Entity Emerging Growth Company | false |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Common Stock [Member] | |
| Entity Listings [Line Items] | |
| Title of 12(b) Security | Common Stock, par value $1.00 per share |
| Trading Symbol | JEF |
| Security Exchange Name | NYSE |
| 4.850% Senior Notes Due 2027 [Member] | |
| Entity Listings [Line Items] | |
| Title of 12(b) Security | 4.850% Senior Notes Due 2027 |
| Trading Symbol | JEF 27A |
| Security Exchange Name | NYSE |
| 5.875% Senior Notes Due 2028 [Member] | |
| Entity Listings [Line Items] | |
| Title of 12(b) Security | 5.875% Senior Notes Due 2028 |
| Trading Symbol | JEF 28 |
| Security Exchange Name | NYSE |
| 2.750% Senior Notes Due 2032 [Member] | |
| Entity Listings [Line Items] | |
| Title of 12(b) Security | 2.750% Senior Notes Due 2032 |
| Trading Symbol | JEF 32A |
| Security Exchange Name | NYSE |
| 6.200% Senior Notes Due 2034 [Member] | |
| Entity Listings [Line Items] | |
| Title of 12(b) Security | 6.200% Senior Notes Due 2034 |
| Trading Symbol | JEF 34 |
| Security Exchange Name | NYSE |
