Assets that have been segregated in trusts to cover the unfunded non-qualified benefit plans.

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- Definition

The unfunded accumulated benefit obligation related to non-qualified benefit plans.

+ References

No definition available.

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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

Amount of contributions expected to be received by defined benefit plan from employer in next fiscal year following latest fiscal year.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-Section 50
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- Definition

Amount of gain (loss) recognized in net periodic benefit (cost) credit from irrevocable action relieving primary responsibility for benefit obligation and eliminating risk related to obligation and assets used to effect settlement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 20
-Section 50
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- Definition

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

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 360
-Section S99
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PENSION PLANS AND POST-RETIREMENT BENEFITS - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2017	Dec. 31, 2019	Dec. 31, 2019	Dec. 31, 2018
Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Settlement and special termination benefits	$ 15.6	$ 0.4
Non-qualified benefit obligations	49.4				$ 46.9
Funded by trusts containing assets	45.5				43.8
Contributions to plans in next year	128.1
Post-Retirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Settlement and special termination benefits	0.0	0.0
Contributions to plans in next year	3.8
Evergy Kansas Central \| Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Settlement and special termination benefits	0.0	0.4
Non-qualified benefit obligations	26.0				24.8
Funded by trusts containing assets	31.7				$ 30.6
Contributions to plans in next year	45.5
Evergy Kansas Central \| Post-Retirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Settlement and special termination benefits	0.0	0.0
Contributions to plans in next year	0.8
Evergy Metro \| Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Settlement and special termination benefits	23.0	16.3
Contributions to plans in next year	82.6
Evergy Metro \| Post-Retirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Settlement and special termination benefits	0.0	$ 0.0
Contributions to plans in next year	$ 3.0
Wolf Creek
Defined Benefit Plan Disclosure [Line Items]
Jointly owned utility plant, proportionate ownership share			94.00%	94.00%	47.00%
Wolf Creek \| Evergy Kansas South Inc
Defined Benefit Plan Disclosure [Line Items]
Jointly owned utility plant, proportionate ownership share			47.00%
Wolf Creek \| Evergy Kansas Central
Defined Benefit Plan Disclosure [Line Items]
Jointly owned utility plant, proportionate ownership share				47.00%	47.00%
Wolf Creek \| Evergy Metro
Defined Benefit Plan Disclosure [Line Items]
Jointly owned utility plant, proportionate ownership share			47.00%	47.00%