XML 132 R100.htm IDEA: XBRL DOCUMENT
v3.20.4

PENSION PLANS AND POST-RETIREMENT BENEFITS - Target Asset Allocations (Details) | Dec. 31, 2020
--- | ---
Evergy Kansas Central | Pension Benefits | Domestic equities |
Defined Benefit Plan Disclosure [Line Items] |
Defined benefit plan assets, target allocation, percentage | 29.00%
Evergy Kansas Central | Pension Benefits | International equities |
Defined Benefit Plan Disclosure [Line Items] |
Defined benefit plan assets, target allocation, percentage | 20.00%
Evergy Kansas Central | Pension Benefits | Bonds |
Defined Benefit Plan Disclosure [Line Items] |
Defined benefit plan assets, target allocation, percentage | 36.00%
Evergy Kansas Central | Pension Benefits | Mortgage & asset backed securities |
Defined Benefit Plan Disclosure [Line Items] |
Defined benefit plan assets, target allocation, percentage | 0.00%
Evergy Kansas Central | Pension Benefits | Real estate investments |
Defined Benefit Plan Disclosure [Line Items] |
Defined benefit plan assets, target allocation, percentage | 4.00%
Evergy Kansas Central | Pension Benefits | Other investments |
Defined Benefit Plan Disclosure [Line Items] |
Defined benefit plan assets, target allocation, percentage | 11.00%
Evergy Kansas Central | Post-Retirement Benefits | Domestic equities |
Defined Benefit Plan Disclosure [Line Items] |
Defined benefit plan assets, target allocation, percentage | 33.00%
Evergy Kansas Central | Post-Retirement Benefits | International equities |
Defined Benefit Plan Disclosure [Line Items] |
Defined benefit plan assets, target allocation, percentage | 22.00%
Evergy Kansas Central | Post-Retirement Benefits | Bonds |
Defined Benefit Plan Disclosure [Line Items] |
Defined benefit plan assets, target allocation, percentage | 45.00%
Evergy Kansas Central | Post-Retirement Benefits | Mortgage & asset backed securities |
Defined Benefit Plan Disclosure [Line Items] |
Defined benefit plan assets, target allocation, percentage | 0.00%
Evergy Kansas Central | Post-Retirement Benefits | Real estate investments |
Defined Benefit Plan Disclosure [Line Items] |
Defined benefit plan assets, target allocation, percentage | 0.00%
Evergy Kansas Central | Post-Retirement Benefits | Other investments |
Defined Benefit Plan Disclosure [Line Items] |
Defined benefit plan assets, target allocation, percentage | 0.00%
Evergy Metro | Pension Benefits | Domestic equities |
Defined Benefit Plan Disclosure [Line Items] |
Defined benefit plan assets, target allocation, percentage | 30.00%
Evergy Metro | Pension Benefits | International equities |
Defined Benefit Plan Disclosure [Line Items] |
Defined benefit plan assets, target allocation, percentage | 24.00%
Evergy Metro | Pension Benefits | Bonds |
Defined Benefit Plan Disclosure [Line Items] |
Defined benefit plan assets, target allocation, percentage | 33.00%
Evergy Metro | Pension Benefits | Mortgage & asset backed securities |
Defined Benefit Plan Disclosure [Line Items] |
Defined benefit plan assets, target allocation, percentage | 0.00%
Evergy Metro | Pension Benefits | Real estate investments |
Defined Benefit Plan Disclosure [Line Items] |
Defined benefit plan assets, target allocation, percentage | 5.00%
Evergy Metro | Pension Benefits | Other investments |
Defined Benefit Plan Disclosure [Line Items] |
Defined benefit plan assets, target allocation, percentage | 9.00%
Evergy Metro | Post-Retirement Benefits | Domestic equities |
Defined Benefit Plan Disclosure [Line Items] |
Defined benefit plan assets, target allocation, percentage | 3.00%
Evergy Metro | Post-Retirement Benefits | International equities |
Defined Benefit Plan Disclosure [Line Items] |
Defined benefit plan assets, target allocation, percentage | 0.00%
Evergy Metro | Post-Retirement Benefits | Bonds |
Defined Benefit Plan Disclosure [Line Items] |
Defined benefit plan assets, target allocation, percentage | 85.00%
Evergy Metro | Post-Retirement Benefits | Mortgage & asset backed securities |
Defined Benefit Plan Disclosure [Line Items] |
Defined benefit plan assets, target allocation, percentage | 4.00%
Evergy Metro | Post-Retirement Benefits | Real estate investments |
Defined Benefit Plan Disclosure [Line Items] |
Defined benefit plan assets, target allocation, percentage | 0.00%
Evergy Metro | Post-Retirement Benefits | Other investments |
Defined Benefit Plan Disclosure [Line Items] |
Defined benefit plan assets, target allocation, percentage | 7.00%

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

X
- Definition Percentage of target investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 55 -Paragraph 17 -URI http://asc.fasb.org/extlink&oid=118257860&loc=d3e4179-114921 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(i) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 + Details
Name: | us-gaap_DefinedBenefitPlanPlanAssetsTargetAllocationPercentage
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Details
Name: | dei_LegalEntityAxis=evrg_EvergyKansasCentralIncMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RetirementPlanTypeAxis=us-gaap_PensionPlansDefinedBenefitMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis=us-gaap_DefinedBenefitPlanEquitySecuritiesUsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis=us-gaap_DefinedBenefitPlanEquitySecuritiesNonUsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis=evrg_DefinedBenefitPlanBondMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis=us-gaap_AssetBackedSecuritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis=us-gaap_DefinedBenefitPlanRealEstateMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis=evrg_DefinedBenefitPlanOtherInvestmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RetirementPlanTypeAxis=us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | dei_LegalEntityAxis=evrg_EvergyMetroIncMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |