Business Segments - Segment Net Income (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Segment Reporting Information [Line Items]
Net Operating Income									$ 53.8	$ 47.1	$ 145.2
Income from Continuing Operations	(1.7)	55.6	1.6	36.3	25.0	1.1	(9.4)	45.0	91.8	61.7	162.4
Operating Segments [Member]
Segment Reporting Information [Line Items]
Net Operating Income									79.9	73.6	159.6
Kemper Preferred [Member]
Segment Reporting Information [Line Items]
Net Operating Income									(11.2)	(17.6)	52.9
Kemper Specialty [Member]
Segment Reporting Information [Line Items]
Net Operating Income									1.2	19.8	21.0
Kemper Direct [Member]
Segment Reporting Information [Line Items]
Net Operating Income									(0.9)	(27.5)	(1.7)
Life and Health Insurance [Member]
Segment Reporting Information [Line Items]
Net Operating Income									90.8	98.9	87.4
Unallocated Amount to Segment [Member]
Segment Reporting Information [Line Items]
Net Operating Income									(26.1)	(26.5)	(14.4)
Net Realized Gains on Sale of Investments, Net of Tax									42.5	21.9	27.9
Net Impairment Losses Recognized in Earnings, Net of Tax									$ 4.5	$ 7.3	$ 10.7