RECEIVABLES - Narrative (Details) - USD ($)	Mar. 31, 2020	Dec. 31, 2019
Entity Information [Line Items]
Other receivables, contracts with customers	$ 45,800,000	$ 42,000,000.0
Accounts receivable pledged as collateral	322,000,000.0	339,000,000.0
Evergy Kansas Central
Entity Information [Line Items]
Other receivables, contracts with customers	43,900,000	37,700,000
Accounts receivable pledged as collateral	159,000,000.0	171,000,000.0
Evergy Metro
Entity Information [Line Items]
Other receivables, contracts with customers	1,300,000	1,200,000
Accounts receivable pledged as collateral	113,000,000.0	$ 118,000,000.0
Maximum amount of outstanding principal under receivables agreement	130,000,000.0
Borrowings From Mid October Through Mid June \| Evergy Kansas Central
Entity Information [Line Items]
Maximum amount of outstanding principal under receivables agreement	185,000,000.0
Borrowing From Mid June Through Expiration \| Evergy Kansas Central
Entity Information [Line Items]
Maximum amount of outstanding principal under receivables agreement	200,000,000.0
Borrowing From Mid June Through Expiration \| Evergy Missouri West Inc
Entity Information [Line Items]
Maximum amount of outstanding principal under receivables agreement	65,000,000.0
Borrowings From Mid-November Through Mid-June \| Evergy Missouri West Inc
Entity Information [Line Items]
Maximum amount of outstanding principal under receivables agreement	$ 50,000,000.0

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.

No definition available.

+ Details

Name:	dei_EntityInformationLineItems
Namespace Prefix:	dei_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Maximum amount of outstanding principal under receivables agreement

+ References

No definition available.

+ Details

Name:	evrg_MaximumAmountOfOutstandingPrincipalUnderReceivablesAgreement
Namespace Prefix:	evrg_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The amount of other receivables resulting from contracts with customers.

+ References

No definition available.

+ Details

Name:	evrg_OtherReceivablesContractsWithCustomers
Namespace Prefix:	evrg_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Carrying amount of financial assets accounted for as secured borrowings recognized in the transferor's statement of financial position at the end of each period presented.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 50
-Paragraph 1A
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=109249958&loc=SL6224234-111729

+ Details

Name:	us-gaap_TransfersAccountedForAsSecuredBorrowingsAssetsCarryingAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

Name:	dei_LegalEntityAxis=evrg_EvergyKansasCentralIncMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	dei_LegalEntityAxis=evrg_EvergyMetroIncMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=evrg_BorrowingsFromMidOctoberThroughMidJuneMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=evrg_BorrowingFromMidJuneThroughExpirationMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	dei_LegalEntityAxis=evrg_EvergyMissouriWestIncMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=evrg_BorrowingsFromMidNovemberThroughMidJuneMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: