Catatrophe Reinsurance - Catatrophe Reinsurance Premiums (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Liability for Catastrophe Claims [Line Items]
Ceded Catastrphoe Reinsurance Premiums	$ 42.5	$ 40.7	$ 43.9
Catastrophe [Member]
Liability for Catastrophe Claims [Line Items]
Ceded Catastrphoe Reinsurance Premiums	27.1	23.2	26.6
Kemper Preferred [Member] | Catastrophe [Member]
Liability for Catastrophe Claims [Line Items]
Ceded Catastrphoe Reinsurance Premiums	24.6	20.0	21.9
Kemper Specialty [Member] | Catastrophe [Member]
Liability for Catastrophe Claims [Line Items]
Ceded Catastrphoe Reinsurance Premiums	0.1	0.1	0.3
Kemper Direct [Member] | Catastrophe [Member]
Liability for Catastrophe Claims [Line Items]
Ceded Catastrphoe Reinsurance Premiums	0.4	0.8	0.8
Life and Health Insurance [Member] | Catastrophe [Member]
Liability for Catastrophe Claims [Line Items]
Ceded Catastrphoe Reinsurance Premiums	2.0	2.3	3.6
Reinsurance Restatement Premiums		$ (0.2)	$ 0.6