Document and Entity Information - USD ($) $ in Billions	12 Months Ended
	Dec. 31, 2020	Jan. 31, 2021	Jun. 30, 2020
Cover [Abstract]
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2020
Document Transition Report	false
Entity File Number	001-18298
Entity Registrant Name	Kemper    Corporation
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
Title of 12(b) Security	Common Stock, $0.10 par value per share
Trading Symbol	KMPR
Security Exchange Name	NYSE
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
ICFR Auditor Attestation Flag	true
Entity Shell Company	false
Entity Public Float			$ 4.7
Entity Common Stock, Shares Outstanding (in shares)		65,454,685
Documents Incorporated by Reference	Portions of the Proxy Statement for the 2021 Annual Meeting of Shareholders are incorporated by reference into Part III.
Entity Central Index Key	0000860748
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	FY
Amendment Flag	false