v2.4.0.6

Relationships with Mutual Insurance Companies (Details) (USD $) In Millions, unless otherwise specified | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2012 | Sep. 30, 2012
ORCC [Member] |  |
Relationships with Mutual Insurance Companies [Line Items] |  |
Number of Company Employee Board Members |  | 9
Number of Board of Director Members |  | 9
Capitol [Member] |  |
Relationships with Mutual Insurance Companies [Line Items] |  |
Number of Company Employee Board Members |  | 5
Number of Board of Director Members |  | 5
ORCC [Member] | Trinity [Member] |  |
Relationships with Mutual Insurance Companies [Line Items] |  |
Assumed Premiums Earned, Other Insurance Percentage |  | 100.00%
Capitol [Member] | Trinity [Member] |  |
Relationships with Mutual Insurance Companies [Line Items] |  |
Assumed Premiums Earned, Other Insurance Percentage |  | 100.00%
Change in Policyholder Benefits and Incurred Losses and LAE as Result of Quota Share Revision | $ (2.6) |

X
- Definition Premiums assumed for all other insurance from other insurers as a result of reinsurance arrangements, percentage. + References No definition available. + Details
Name: | kmpr_AssumedPremiumsOtherInsurancePercentage
Namespace Prefix: | kmpr_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition The amount of the change to Policyholder Benefits and Incurred Losses and LAE related to the revision of an existing quota share reinsurance agreement. + References No definition available. + Details
Name: | kmpr_ChangeInPolicyholderBenefitsAndIncurredLossesAndLaeAsResultOfQuotaShareRevision
Namespace Prefix: | kmpr_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Number of Board of Director Members + References No definition available. + Details
Name: | kmpr_NumberOfBoardOfDirectorMembers
Namespace Prefix: | kmpr_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number of Company Employee Board Members + References No definition available. + Details
Name: | kmpr_NumberOfCompanyEmployeeBoardMembers
Namespace Prefix: | kmpr_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | kmpr_RelationshipsWithMutualInsuranceCompaniesLineItems
Namespace Prefix: | kmpr_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration