Income Taxes (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023
Income Tax Disclosure [Abstract]
Income tax expense (benefit) attributable to Kemper Corporation	$ (18,900,000)	$ 44,400,000	$ (53,400,000)
Effective income tax rate reconciliation, percent	(20.40%)	(23.30%)	(19.50%)	(21.20%)
Income Tax (Expense) Benefit	$ (18,500,000)	$ 44,400,000	$ (52,400,000)	$ 87,000,000.0
Unrecognized tax benefits	$ 0		0		$ 0
Proceeds from income tax refund, federal				113,600,000
Income tax paid, state and local, after refund received			600,000	$ 100,000
Income tax paid, federal, after refund received			$ 9,900,000