XML 148 R124.htm IDEA: XBRL DOCUMENT
v3.8.0.1

Catastrophe Reinsurance - Coverage for Catastrophe Reinsurance (Details) - Property and Casualty Insurance [Member] - USD ($) | 12 Months Ended
--- | ---
Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014
Retained [Member] |  |  |  |
Liability for Catastrophe Claims [Line Items] |  |  |  |
Reinsurance Retention Policy, Reinsured Risk, Percentage | 0.00% | 0.00% | 0.00% |
First Layer of Coverage [Member] |  |  |  |
Liability for Catastrophe Claims [Line Items] |  |  |  |
Reinsurance Retention Policy, Excess Retention, Percentage | 95.00% | 95.00% | 95.00% |
Second Layer of Coverage [Member] |  |  |  |
Liability for Catastrophe Claims [Line Items] |  |  |  |
Reinsurance Retention Policy, Excess Retention, Percentage | 31.70% | 95.00% | 95.00% | 63.30%
Minimum [Member] | Retained [Member] |  |  |  |
Liability for Catastrophe Claims [Line Items] |  |  |  |
Reinsurance Retention Policy, Amount Retained | $ 0 | $ 0 | $ 0 |
Minimum [Member] | First Layer of Coverage [Member] |  |  |  |
Liability for Catastrophe Claims [Line Items] |  |  |  |
Reinsurance Retention Policy, Excess Retention, Amount Reinsured | 50,000,000 | 50,000,000 | 50,000,000 |
Minimum [Member] | Second Layer of Coverage [Member] |  |  |  |
Liability for Catastrophe Claims [Line Items] |  |  |  |
Reinsurance Retention Policy, Excess Retention, Amount Reinsured | 150,000,000 | 150,000,000 | 150,000,000 | $ 150,000,000
Maximum [Member] | Retained [Member] |  |  |  |
Liability for Catastrophe Claims [Line Items] |  |  |  |
Reinsurance Retention Policy, Amount Retained | 50,000,000 | 50,000,000 | 50,000,000 |
Maximum [Member] | First Layer of Coverage [Member] |  |  |  |
Liability for Catastrophe Claims [Line Items] |  |  |  |
Reinsurance Retention Policy, Excess Retention, Amount Reinsured | 150,000,000 | 150,000,000 | 150,000,000 |
Maximum [Member] | Second Layer of Coverage [Member] |  |  |  |
Liability for Catastrophe Claims [Line Items] |  |  |  |
Reinsurance Retention Policy, Excess Retention, Amount Reinsured | $ 250,000,000 | $ 350,000,000 | $ 350,000,000 | $ 350,000,000

X
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
Name: | us-gaap_LiabilityForCatastropheClaimsLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Stated amount that is the upper retention limit per entity policy. + References No definition available. + Details
Name: | us-gaap_ReinsuranceRetentionPolicyAmountRetained
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of risk reinsured in excess of stated retention per company policy. + References No definition available. + Details
Name: | us-gaap_ReinsuranceRetentionPolicyExcessRetentionAmountReinsured
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Percentage of risk reinsured in excess of stated retention per entity policy. + References No definition available. + Details
Name: | us-gaap_ReinsuranceRetentionPolicyExcessRetentionPercentage
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Percentage of risk reinsured on insurance products per entity policy. + References No definition available. + Details
Name: | us-gaap_ReinsuranceRetentionPolicyReinsuredRiskPercentage
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_StatementBusinessSegmentsAxis=kmpr_PropertyAndCasualtyInsuranceMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | kmpr_TierIdentifierAxis=kmpr_RetainedMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | kmpr_TierIdentifierAxis=kmpr_FirstLayerOfCoverageMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | kmpr_TierIdentifierAxis=kmpr_SecondLayerOfCoverageMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RangeAxis=us-gaap_MinimumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RangeAxis=us-gaap_MaximumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |