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EQUITY COMPENSATION - Narrative (Details) $ in Millions |  | 12 Months Ended
--- | --- | ---
Jun. 04, 2018 USD ($) | Dec. 31, 2020 | Dec. 31, 2018 USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Compensation expense |  |  | $ 14.6
Expected volatility, maximum |  | 17.00% |
Expected dividend yield |  | 2.93% |
Risk-free interest rate, maximum |  | 0.72% |
Evergy Kansas Central |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Compensation expense |  |  | $ 14.6
Great Plains Energy |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Exchange ratio | 0.5981 |  |
Share-based Payment Arrangement | Great Plains Energy |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Fair value of shares issued | $ 12.5 |  |

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- Definition The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (f)(2)(iii) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition The estimated measure of the maximum percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period. + References No definition available. + Details
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