The accredited capacity of the jointly owned electric utility plant, in megawatts.

No definition available.

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- Definition

Leasehold Interest Percentage

+ References

No definition available.

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- Definition

The period end amount owned by the reporting utility of a jointly owned utility plant in service.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 980
-SubTopic 360
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 10.C)
-URI http://asc.fasb.org/extlink&oid=115995737&loc=d3e659983-123033

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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.

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- Definition

The period end amount of construction work in progress at a jointly owned electricity generation plant.

+ References

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- Definition

The period end amount of accumulated depreciation in a jointly owned electricity generation plant.

+ References

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- Definition

The proportionate share of interest (percent) in a jointly owned utility plant.

+ References

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- Definition

The carrying amount as of the balance sheet of nuclear fuel held as property plant and equipment. This amount is net of amortization based on the energy produced over the life of the fuel.

+ 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 210.5-02.13(b))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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JOINTLY-OWNED ELECTRIC UTILITY PLANTS (Details) $ in Millions	Dec. 31, 2020 USD ($)	Dec. 31, 2020 Rate	Dec. 31, 2020 MW	Dec. 31, 2020	Dec. 31, 2019 USD ($)
Jointly Owned Utility Plant Interests [Line Items]
Nuclear fuel, net	$ 155.9				$ 128.5
Wolf Creek Unit
Jointly Owned Utility Plant Interests [Line Items]
Jointly owned utility plant, proportionate ownership share		94.00%		94.00%
Electric plant in service	4,059.1
Accumulated depreciation	1,970.3
Nuclear fuel, net	155.9
Construction work in progress	183.5
Accredited capacity \| MW			1,108
La Cygne Units
Jointly Owned Utility Plant Interests [Line Items]
Jointly owned utility plant, proportionate ownership share \| Rate		100.00%
Electric plant in service	2,207.6
Accumulated depreciation	779.4
Nuclear fuel, net	0.0
Construction work in progress	27.7
Accredited capacity \| MW			1,426
Iatan No. 1 Unit
Jointly Owned Utility Plant Interests [Line Items]
Jointly owned utility plant, proportionate ownership share \| Rate		88.00%
Electric plant in service	773.3
Accumulated depreciation	265.7
Nuclear fuel, net	0.0
Construction work in progress	10.3
Accredited capacity \| MW			618
Iatan No. 2 Unit
Jointly Owned Utility Plant Interests [Line Items]
Jointly owned utility plant, proportionate ownership share \| Rate		73.00%
Electric plant in service	1,404.3
Accumulated depreciation	459.3
Nuclear fuel, net	0.0
Construction work in progress	10.7
Accredited capacity \| MW			640
Iatan Common
Jointly Owned Utility Plant Interests [Line Items]
Jointly owned utility plant, proportionate ownership share \| Rate		79.00%
Electric plant in service	499.7
Accumulated depreciation	127.8
Nuclear fuel, net	0.0
Construction work in progress	4.4
Jeffrey Energy Center
Jointly Owned Utility Plant Interests [Line Items]
Jointly owned utility plant, proportionate ownership share \| Rate		100.00%
Electric plant in service	2,435.4
Accumulated depreciation	984.1
Nuclear fuel, net	0.0
Construction work in progress	84.1
Accredited capacity \| MW			2,012
State Line
Jointly Owned Utility Plant Interests [Line Items]
Jointly owned utility plant, proportionate ownership share \| Rate		40.00%
Electric plant in service	115.0
Accumulated depreciation	80.6
Nuclear fuel, net	0.0
Construction work in progress	12.9
Accredited capacity \| MW			200
Evergy Kansas Central
Jointly Owned Utility Plant Interests [Line Items]
Nuclear fuel, net	77.7				63.9
Evergy Kansas Central \| Wolf Creek Unit
Jointly Owned Utility Plant Interests [Line Items]
Jointly owned utility plant, proportionate ownership share \| Rate		47.00%
Electric plant in service	1,995.2
Accumulated depreciation	956.6
Nuclear fuel, net	77.7
Construction work in progress	77.2
Accredited capacity \| MW			554
Evergy Kansas Central \| La Cygne Units
Jointly Owned Utility Plant Interests [Line Items]
Jointly owned utility plant, proportionate ownership share \| Rate		50.00%
Electric plant in service	1,046.5
Accumulated depreciation	446.2
Nuclear fuel, net	0.0
Construction work in progress	10.6
Accredited capacity \| MW			713
Evergy Kansas Central \| Jeffrey Energy Center
Jointly Owned Utility Plant Interests [Line Items]
Jointly owned utility plant, proportionate ownership share \| Rate		92.00%
Electric plant in service	2,229.5
Accumulated depreciation	895.3
Nuclear fuel, net	0.0
Construction work in progress	77.3
Accredited capacity \| MW			1,837
Evergy Kansas Central \| State Line
Jointly Owned Utility Plant Interests [Line Items]
Jointly owned utility plant, proportionate ownership share \| Rate		40.00%
Electric plant in service	115.0
Accumulated depreciation	80.6
Nuclear fuel, net	0.0
Construction work in progress	12.9
Accredited capacity \| MW			200
Evergy Metro
Jointly Owned Utility Plant Interests [Line Items]
Nuclear fuel, net	78.2				$ 64.6
Evergy Metro \| Wolf Creek Unit
Jointly Owned Utility Plant Interests [Line Items]
Jointly owned utility plant, proportionate ownership share		47.00%		47.00%
Electric plant in service	2,063.9
Accumulated depreciation	1,013.7
Nuclear fuel, net	78.2
Construction work in progress	106.3
Accredited capacity \| MW			554
Evergy Metro \| La Cygne Units
Jointly Owned Utility Plant Interests [Line Items]
Jointly owned utility plant, proportionate ownership share \| Rate		50.00%
Electric plant in service	1,161.1
Accumulated depreciation	333.2
Nuclear fuel, net	0.0
Construction work in progress	17.1
Accredited capacity \| MW			713
Evergy Metro \| Iatan No. 1 Unit
Jointly Owned Utility Plant Interests [Line Items]
Jointly owned utility plant, proportionate ownership share \| Rate		70.00%
Electric plant in service	600.2
Accumulated depreciation	204.7
Nuclear fuel, net	0.0
Construction work in progress	8.3
Accredited capacity \| MW			492
Evergy Metro \| Iatan No. 2 Unit
Jointly Owned Utility Plant Interests [Line Items]
Jointly owned utility plant, proportionate ownership share \| Rate		55.00%
Electric plant in service	1,065.3
Accumulated depreciation	397.4
Nuclear fuel, net	0.0
Construction work in progress	8.0
Accredited capacity \| MW			482
Evergy Metro \| Iatan Common
Jointly Owned Utility Plant Interests [Line Items]
Jointly owned utility plant, proportionate ownership share \| Rate		61.00%
Electric plant in service	396.5
Accumulated depreciation	110.5
Nuclear fuel, net	0.0
Construction work in progress	$ 3.1
Subsidiaries \| La Cygne Unit 2
Jointly Owned Utility Plant Interests [Line Items]
Leasehold interest percentage				50.00%
Subsidiaries \| Evergy Kansas Central \| La Cygne Unit 2
Jointly Owned Utility Plant Interests [Line Items]
Leasehold interest percentage				50.00%