Business Segments - Segment Revenues (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Segment Reporting Information [Line Items]
Earned Premiums	$ 495.6	$ 507.5	$ 512.8	$ 509.9	$ 520.8	$ 527.3	$ 529.8	$ 529.2	$ 2,025.8	$ 2,107.1	$ 2,173.6
Net Investment Income	76.9	82.4	74.6	80.8	72.9	70.4	75.2	77.4	314.7	295.9	298.0
Other Income	0.3	0.1	0.2	0.2	0.2	0.2	0.2	0.2	0.8	0.8	1.0
Total Revenues	586.0	635.7	588.9	615.9	596.6	645.6	608.9	611.2	2,426.5	2,462.3	2,495.0
Net Realized Gains on Sales of Investments	20.8	49.1	2.3	26.9	5.5	50.9	4.1	4.9	99.1	65.4	33.7
Net Impairment Losses Recognized in Earnings	(7.6)	(3.4)	(1.0)	(1.9)	(2.8)	(3.2)	(0.4)	(0.5)	(13.9)	(6.9)	(11.3)
Operating Segments [Member]
Segment Reporting Information [Line Items]
Total Revenues									2,327.3	2,390.1	2,464.1
Kemper Preferred [Member]
Segment Reporting Information [Line Items]
Earned Premiums									876.7	879.4	859.8
Net Investment Income									55.7	45.0	48.8
Other Income									0.2	0.4	0.3
Total Revenues									932.6	924.8	908.9
Kemper Specialty [Member]
Segment Reporting Information [Line Items]
Earned Premiums									392.8	419.8	445.2
Net Investment Income									21.8	19.0	22.8
Other Income									0.3	0.3	0.5
Total Revenues									414.9	439.1	468.5
Kemper Direct [Member]
Segment Reporting Information [Line Items]
Earned Premiums									123.4	168.0	222.7
Net Investment Income									13.4	13.9	17.4
Other Income									0	0	0.1
Total Revenues									136.8	181.9	240.2
Life and Health Insurance [Member]
Segment Reporting Information [Line Items]
Earned Premiums									632.9	639.9	645.9
Net Investment Income									209.9	204.3	200.5
Other Income									0.2	0.1	0.1
Total Revenues									843.0	844.3	846.5
Segment Reconciling Items [Member]
Segment Reporting Information [Line Items]
Other Income									$ 14.0	$ 13.7	$ 8.5