SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Fuel Inventory and Supplies (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Inventory [Line Items]
Fuel inventory	$ 160.9	$ 145.0
Supplies	405.8	359.5
Fuel inventory and supplies	566.7	504.5
Evergy Kansas Central
Inventory [Line Items]
Fuel inventory	74.3	79.3
Supplies	208.9	197.1
Fuel inventory and supplies	283.2	276.4
Evergy Metro
Inventory [Line Items]
Fuel inventory	62.0	44.9
Supplies	149.0	125.5
Fuel inventory and supplies	$ 211.0	$ 170.4

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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