SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Fuel Inventory and Supplies (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Inventory [Line Items]
Fuel inventory	$ 145.0	$ 146.4
Supplies	359.5	335.2
Fuel inventory and supplies	504.5	481.6
Evergy Kansas Central
Inventory [Line Items]
Fuel inventory	79.3	80.2
Supplies	197.1	186.2
Fuel inventory and supplies	276.4	266.4
Evergy Metro
Inventory [Line Items]
Fuel inventory	44.9	46.1
Supplies	125.5	116.9
Fuel inventory and supplies	$ 170.4	$ 163.0

Energy Related Inventory, Supplies

No definition available.

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- Definition

Carrying amount as of the balance sheet date of merchandise, goods, commodities, or supplies relating to a source of usable power held for future sale or future use in manufacturing or production process.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.6(a))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

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- Definition

Carrying amount as of the balance sheet date of coal, which is a combustible rock or minerals which are extracted from the ground and used as fuel.

+ References

+ Details

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- 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

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- Details

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