RECEIVABLES - Narrative (Details) - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Entity Information [Line Items]
Other receivables, contracts with customers	$ 58.8	$ 42.0
Accounts receivable pledged as collateral	395.0	339.0
Evergy Kansas Central
Entity Information [Line Items]
Other receivables, contracts with customers	49.9	37.7
Accounts receivable pledged as collateral	200.0	171.0
Evergy Metro
Entity Information [Line Items]
Other receivables, contracts with customers	6.1	1.2
Accounts receivable pledged as collateral	130.0	$ 118.0
Maximum amount of outstanding principal under receivables agreement	130.0
Borrowings From Mid October Through Mid June \| Evergy Kansas Central
Entity Information [Line Items]
Maximum amount of outstanding principal under receivables agreement	185.0
Borrowing From Mid June Through Expiration \| Evergy Kansas Central
Entity Information [Line Items]
Maximum amount of outstanding principal under receivables agreement	200.0
Borrowing From Mid June Through Expiration \| Evergy Missouri West Inc
Entity Information [Line Items]
Maximum amount of outstanding principal under receivables agreement	65.0
Borrowings From Mid-November Through Mid-June \| Evergy Missouri West Inc
Entity Information [Line Items]
Maximum amount of outstanding principal under receivables agreement	$ 50.0

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- Definition

Maximum amount of outstanding principal under receivables agreement

+ References

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- Definition

The amount of other receivables resulting from contracts with customers.

+ References

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- 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

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