| Document and Entity Information | Apr. 29, 2021 |
| Cover [Abstract] | |
| Document Type | 8-K |
| Document Period End Date | Apr. 29, 2021 |
| Entity Registrant Name | Kemper Corporation |
| Entity Central Index Key | 0000860748 |
| Amendment Flag | false |
| Entity File Number | 001-18298 |
| Entity Incorporation, State or Country Code | DE |
| Entity Tax Identification Number | 95-4255452 |
| Entity Address, Address Line One | 200 E. Randolph Street |
| Entity Address, Address Line Two | Suite 3300 |
| Entity Address, City or Town | Chicago |
| Entity Address, State or Province | IL |
| Entity Address, Postal Zip Code | 60601 |
| City Area Code | 312 |
| Local Phone Number | 661-4600 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Title of 12(b) Security | Common Stock, par value $0.10 per share |
| Trading Symbol | KMPR |
| Security Exchange Name | NYSE |
| Entity Emerging Growth Company | false |
