Condensed Consolidated Statements of Income (Loss) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Income Statement [Abstract]
Earned Premiums (Changes in Deferred Profit Liability for the Three Months Ended: 2024 - $19.7; 2023 - $19.2)	$ 1,031.9	$ 1,180.9
Net Investment Income	100.4	101.8
Change in Value of Alternative Energy Partnership Investments	0.4	0.7
Other Income	1.8	1.2
Change in Fair Value of Equity and Convertible Securities	3.4	1.7
Net Realized Investment Gains	6.6	6.4
Impairment Losses	(1.5)	2.1
Total Revenues	1,143.0	1,294.8
Expenses:
Policyholders’ Benefits and Incurred Losses and Loss Adjustment Expenses (Changes in Liability for Future Policyholder Benefits for the Three Months Ended: 2024 - $6.0 ; 2023 - $1.9)	756.0	1,052.0
Insurance Expenses	240.7	269.3
Interest and Other Expenses	59.7	77.4
Total Expenses	1,056.4	1,398.7
Income (Loss) before Income Taxes	86.6	(103.9)
Income Tax (Expense) Benefit	(16.4)	23.8
Net Income (Loss)	70.2	(80.1)
Less: Net (Loss) Income attributable to Noncontrolling Interest	(1.1)	0.0
Net Income (Loss) attributable to Kemper Corporation	$ 71.3	$ (80.1)
Net Income (Loss) attributable to Kemper Corporation per Unrestricted Share:
Basic (in dollars per share)	$ 1.11	$ (1.25)
Diluted (in dollars per share)	$ 1.10	$ (1.25)