Annual Awards of Deferred Stock Units to be Issued to each Non-Employee Director

No definition available.

Name:	kmpr_AnnualAwardsofDeferredStockUnitstobeIssuedtoeachNonEmployeeDirector
Namespace Prefix:	kmpr_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of Additional Shares To Be Granted If Maximum Perfornance Level Is Met or Exceeded

+ References

No definition available.

+ Details

Name:	kmpr_NumberOfAdditionalSharesToBeGrantedIfMaximumPerfornanceLevelIsMetOrExceeded
Namespace Prefix:	kmpr_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

Performance Period

+ References

No definition available.

+ Details

Name:	kmpr_PerformancePeriod
Namespace Prefix:	kmpr_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Reduction in Share Authorization if Maximum Performance Level is Met or Exceeded

+ References

No definition available.

+ Details

Name:	kmpr_ReductionInShareAuthorizationIfMaximumPerformanceLevelIsMetOrExceeded
Namespace Prefix:	kmpr_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

Share Based Compensation Arrangement By Share Based Payment Award, Automatic Annual Grant, Non-Employee Directors, Options

+ References

No definition available.

+ Details

Name:	kmpr_ShareBasedCompensationArrangementByShareBasedPaymentAwardAutomaticAnnualGrantNonEmployeeDirectorsOptions
Namespace Prefix:	kmpr_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Share Based Compensation Arrangement By Share Based Payment Award, Automatic Annual Grant, Non-Employee Directors, Options, Expiration Date

+ References

No definition available.

+ Details

Name:	kmpr_ShareBasedCompensationArrangementByShareBasedPaymentAwardAutomaticAnnualGrantNonEmployeeDirectorsOptionsExpirationDate
Namespace Prefix:	kmpr_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Tax Benefits

+ References

No definition available.

+ Details

Name:	kmpr_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodTaxBenefits
Namespace Prefix:	kmpr_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Deferred Stock Unit, Vested in Period, Fair Value

+ References

No definition available.

+ Details

Name:	kmpr_SharebasedCompensationArrangementbySharebasedPaymentAwardDeferredStockUnitVestedinPeriodFairValue
Namespace Prefix:	kmpr_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Share-based Compensation,Initial Grant For Non-Employee Director, Options

+ References

No definition available.

+ Details

Name:	kmpr_SharebasedCompensationInitialGrantForNonEmployeeDirectorOptions
Namespace Prefix:	kmpr_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

+ References

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

+ References

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue
Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue
Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

+ References

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

+ References

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue
Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

+ References

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

+ References

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodTotalFairValue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

+ References

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue
Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

- 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_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (f)(2)(i)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.D.2)
-URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809

+ Details

Name:	us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of shares (or other type of equity) forfeited during the period.

+ References

No definition available.

+ Details

Name:	us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensationForfeited
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_AwardTypeAxis=us-gaap_RestrictedStockMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_AwardTypeAxis=kmpr_TimeVestedRestrictedStockMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_AwardTypeAxis=kmpr_PerformanceBasedRestrictedStockMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_AwardTypeAxis=kmpr_TimeVestedRestrictedStockUnitsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_AwardTypeAxis=kmpr_PerformanceBasedRestrictedStockUnitsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	kmpr_PerformancePeriodAxis=kmpr_PerformancePeriod2015to2017Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	kmpr_PerformancePeriodAxis=kmpr_PerformancePeriod2014to2016Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	kmpr_PerformancePeriodAxis=kmpr_PerformancePeriod2013To2015Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_SubsequentEventTypeAxis=us-gaap_SubsequentEventMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_TitleOfIndividualAxis=us-gaap_DirectorMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_AwardTypeAxis=us-gaap_EmployeeStockOptionMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Long-term Equity-based Compensation - Activity Related to Nonvested Restricted Stock (Details) - USD ($) $ / shares in Units, $ in Millions			12 Months Ended
	Feb. 04, 2017	Feb. 04, 2016	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total fair value of DSUs that vested during the years			$ 0.5	$ 0.1	$ 0.2
Annual Awards of Deferred Stock Units to be Issued to each Non-Employee Director				500	500
Initial grant for non-employee director, shares				4,000	4,000
Automatic annual grant, non-employee directors, options				4,000	4,000
Automatic annual grant, non-employee directors, options, expiration date				10 years	10 years
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vested in Period, Total Fair Value			1.3	$ 1.4	$ 3.6
Income tax benefit from share-based compensation			$ 0.5	$ 0.5	$ 1.2
Time Vested Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Nonvested Balance at Beginning of Year, Restricted Shares			29,448
Nonvested at Beginning of Year, Weighted Average Grant Date Fair Value (per share)			$ 33.77
Grants in Period			0
Grants in Period, Weighted Average Grant Date Fair Value (per share)			$ 0.00
Vested in Period			(12,098)
Vested in Period, Weighted Average Grant Date Fair Value (per share)			$ 32.32
Forfeited in Period			(1,350)
Forfeited in Period, Weighted Average Grant Date Fair Value (per share)			$ 35.75
Nonvested Balance at End of Year, Restricted Shares			16,000	29,448
Nonvested at End of Year, Weighted Average Grant Date Fair Value (per share)			$ 34.69	$ 33.77
Performance Based Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance period			3 years
Nonvested Balance at Beginning of Year, Restricted Shares			51,400
Nonvested at Beginning of Year, Weighted Average Grant Date Fair Value (per share)			$ 42.12
Grants in Period			0
Grants in Period, Weighted Average Grant Date Fair Value (per share)			$ 0.00
Forfeited in Period			(51,400)
Forfeited in Period, Weighted Average Grant Date Fair Value (per share)			$ 42.12
Nonvested Balance at End of Year, Restricted Shares			0	51,400
Nonvested at End of Year, Weighted Average Grant Date Fair Value (per share)			$ 0.00	$ 42.12
Reduction in share authorization if maximum performance level is met or exceeded (shares)			682,752
Time Vested Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Nonvested Balance at Beginning of Year, Restricted Shares			85,048
Nonvested at Beginning of Year, Weighted Average Grant Date Fair Value (per share)			$ 36.84
Grants in Period			118,622
Grants in Period, Weighted Average Grant Date Fair Value (per share)			$ 31.48
Vested in Period			(26,006)
Vested in Period, Weighted Average Grant Date Fair Value (per share)			$ 33.01
Forfeited in Period			(19,303)
Forfeited in Period, Weighted Average Grant Date Fair Value (per share)			$ 36.03
Nonvested Balance at End of Year, Restricted Shares			158,361	85,048
Nonvested at End of Year, Weighted Average Grant Date Fair Value (per share)			$ 33.56	$ 36.84
Performance Based Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Nonvested Balance at Beginning of Year, Restricted Shares			128,100
Nonvested at Beginning of Year, Weighted Average Grant Date Fair Value (per share)			$ 41.85
Grants in Period			146,788
Grants in Period, Weighted Average Grant Date Fair Value (per share)			$ 29.62
Forfeited in Period			(47,304)
Forfeited in Period, Weighted Average Grant Date Fair Value (per share)			$ 39.04
Nonvested Balance at End of Year, Restricted Shares			227,584	128,100
Nonvested at End of Year, Weighted Average Grant Date Fair Value (per share)			$ 34.55	$ 41.85
Performance Period, 2015 to 2017 [Member] \| Performance Based Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Additional Shares To Be Granted If Maximum Perfornance Level Is Met or Exceeded			46,762
Reduction in share authorization if maximum performance level is met or exceeded (shares)			412,845
Performance Period, 2014 to 2016 [Member] \| Performance Based Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Reduction in share authorization if maximum performance level is met or exceeded (shares)			140,286
Performance Period, 2013 to 2015 [Member] \| Performance Based Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock Issued During Period, Shares, Share-based Compensation, Forfeited		51,400
Subsequent Event [Member] \| Performance Period, 2014 to 2016 [Member] \| Performance Based Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Forfeited in Period	(43,207)
Director [Member] \| Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term			0 years	5 years 6 months	6 years