Evergy (EVRG) 10-Q 8 May 19 2019 Q1 Quarterly report Financial data

Document And Entity Information

Document And Entity Information	3 Months Ended
	Mar. 31, 2019shares
Entity Information [Line Items]
Entity Registrant Name	EVERGY, INC.
Entity Central Index Key	0001711269
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Document Type	10-Q
Document Period End Date	Mar. 31, 2019
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	Q1
Amendment Flag	false
Entity Common Stock, Shares Outstanding	244,098,475
Entity Emerging Growth Company	false
Entity Small Business	false
KANSAS CITY POWER & LIGHT CO
Entity Information [Line Items]
Entity Registrant Name	KANSAS CITY POWER & LIGHT CO
Entity Central Index Key	0000054476
Entity Filer Category	Non-accelerated Filer
Entity Common Stock, Shares Outstanding	1
Entity Emerging Growth Company	false
Entity Small Business	false
WESTAR ENERGY INC /KS
Entity Information [Line Items]
Entity Registrant Name	WESTAR ENERGY INC /KS
Entity Central Index Key	0000054507
Entity Filer Category	Non-accelerated Filer
Entity Common Stock, Shares Outstanding	1
Entity Emerging Growth Company	false
Entity Small Business	false

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
CURRENT ASSETS:
Cash and cash equivalents	$ 133.6	$ 160.3
Restricted cash	414.3	0
Receivables, net	164.8	193.7
Accounts receivable pledged as collateral	359	365
Fuel inventory and supplies	466.5	511
Income taxes receivable	56.7	68
Regulatory assets	266.5	303.9
Prepaid expenses and other assets	66.2	79.1
Total Current Assets	1,927.6	1,681
PROPERTY, PLANT AND EQUIPMENT, NET	18,838.1	18,782.5
OTHER ASSETS:
Regulatory assets	1,731.6	1,757.9
Nuclear decommissioning trust fund	518.3	472.1
Goodwill	2,338.9	2,338.9
Other	535.1	396.5
Total Other Assets	5,123.9	4,965.4
TOTAL ASSETS	26,060.7	25,598.1
CURRENT LIABILITIES:
Current maturities of long-term debt	701.1	705.4
Notes payable and commercial paper	1,311	738.6
Collateralized note payable	359	365
Accounts payable	293.7	451.5
Accrued taxes	222.5	133.6
Accrued interest	150.2	110.9
Regulatory liabilities	34.5	110.2
Asset retirement obligations	52.6	49.8
Other	178.5	171.9
Total Current Liabilities	3,335.4	2,867.2
LONG-TERM LIABILITIES:
Long-term debt, net	7,125.9	6,636.3
Deferred income taxes	1,603.8	1,599.2
Unamortized investment tax credits	372.4	373.2
Regulatory liabilities	2,249.2	2,218.8
Pension and post-retirement liability	994.3	987.6
Asset retirement obligations	645.8	637.3
Other	323.4	236.7
Total Long-Term Liabilities	13,333.6	12,740.2
Commitments and Contingencies (Note 9)
Evergy, Inc. Shareholders' Equity:
Common stock	8,110.4	8,685.2
Retained earnings	1,325.7	1,346
Accumulated other comprehensive loss	(13.2)	(3)
Total Shareholders' Equity	9,422.9	10,028.2
Noncontrolling Interests	(31.2)	(37.5)
Total Equity	9,391.7	9,990.7
TOTAL LIABILITIES AND EQUITY	26,060.7	25,598.1
Variable Interest Entities
CURRENT ASSETS:
PROPERTY, PLANT AND EQUIPMENT, NET	171.1	169.2
CURRENT LIABILITIES:
Current maturities of long-term debt	32.3	30.3
LONG-TERM LIABILITIES:
Long-term debt, net	$ 18.8	$ 51.1

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - shares	Mar. 31, 2019	Dec. 31, 2018
Statement of Financial Position [Abstract]
Common stock - shares authorized (in shares)	600,000,000	600,000,000
Common stock - shares issued (in shares)	244,838,786	255,326,252

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income - USD ($) shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Income Statement [Abstract]
OPERATING REVENUES	$ 1,216.9	$ 600.2
OPERATING EXPENSES:
Fuel and purchased power	330	135.5
SPP network transmission costs	63.5	67.6
Operating and maintenance	306.9	140.1
Depreciation and amortization	213.6	89.6
Taxes other than income tax	93.3	43.9
Total Operating Expenses	1,007.3	476.7
INCOME FROM OPERATIONS	209.6	123.5
OTHER INCOME (EXPENSE):
Investment earnings (loss)	3.2	(0.4)
Other income	8.2	2
Other expense	(19.4)	(10.6)
Total Other Income (Expense), Net	(8)	(9)
Interest expense	91.1	43.8
INCOME BEFORE INCOME TAXES	110.5	70.7
Income tax expense	9.3	9.2
Equity in earnings of equity method investees, net of income taxes	2.2	1.4
NET INCOME	103.4	62.9
Less: Net income attributable to noncontrolling interests	3.9	2.4
Net income attributable to Evergy, Inc.	$ 99.5	$ 60.5
BASIC AND DILUTED EARNINGS PER AVERAGE COMMON SHARE OUTSTANDING ATTRIBUTABLE TO EVERGY (see Note 1)
Basic earnings per common share (in dollars per share)	$ 0.39	$ 0.42
Diluted earnings per common share (in dollars per share)	$ 0.39	$ 0.42
AVERAGE COMMON SHARES OUTSTANDING
Basic (in shares)	252.8	142.6
Diluted (in shares)	253	142.7
COMPREHENSIVE INCOME
Net income	$ 103.4	$ 62.9
Loss on derivative hedging instruments	(13.8)	0
Income tax benefit	3.6	0
Derivative hedging activity, net of tax	(10.2)	0
Total other comprehensive loss	(10.2)	0
Comprehensive income	93.2	62.9
Less: comprehensive income attributable to noncontrolling interest	3.9	2.4
COMPREHENSIVE INCOME	$ 89.3	$ 60.5

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
CASH FLOWS FROM (USED IN) OPERATING ACTIVITIES:
Net income	$ 103.4	$ 62.9
Adjustments to reconcile income to net cash from operating activities:
Depreciation and amortization	213.6	89.6
Amortization of nuclear fuel	14.6	7.7
Amortization of deferred refueling outage	6.5	4
Amortization of corporate-owned life insurance	6.6	5.5
Non-cash compensation	5.4	2.5
Net deferred income taxes and credits	(2)	3.8
Allowance for equity funds used during construction	(0.2)	(1.1)
Payments for asset retirement obligations	(1.2)	(1.9)
Equity in earnings of equity method investees, net of income taxes	(2.2)	(1.4)
Income from corporate-owned life insurance	(9.9)	(0.7)
Other	(1.3)	(1.4)
Changes in working capital items:
Accounts receivable	26.6	46.2
Accounts receivable pledged as collateral	6	0
Fuel inventory and supplies	44.6	6.9
Prepaid expenses and other current assets	35.5	(0.1)
Accounts payable	(119.4)	(24.2)
Accrued taxes	100.2	48.7
Other current liabilities	(74.7)	(11.8)
Changes in other assets	12.8	0.7
Changes in other liabilities	(2.8)	23.7
Cash Flows from Operating Activities	362.1	259.6
CASH FLOWS FROM (USED IN) INVESTING ACTIVITIES:
Additions to property, plant and equipment	(309)	(174.8)
Purchase of securities - trusts	(17.9)	(85.4)
Sale of securities - trusts	15.4	86.1
Investment in corporate-owned life insurance	(2.1)	(1)
Proceeds from investment in corporate-owned life insurance	40.9	2.6
Other investing activities	1.3	(1.6)
Cash Flows used in Investing Activities	(271.4)	(174.1)
CASH FLOWS FROM (USED IN) FINANCING ACTIVITIES:
Short term debt, net	572.4	14.1
Collateralized short-term borrowings, net	(6)	0
Proceeds from long-term debt	494	0
Retirements of long-term debt	(1.1)	0
Retirements of long-term debt of variable interest entities	(30.3)	(28.5)
Borrowings against cash surrender value of corporate-owned life insurance	0.6	0.7
Repayment of borrowings against cash surrender value of corporate-owned life insurance	(30.1)	(1.7)
Cash dividends paid	(119.8)	(57.4)
Repurchase of common stock under repurchase plan	(578.3)	0
Other financing activities	(4.5)	(4.9)
Cash Flows used in Financing Activities	296.9	(77.7)
NET CHANGE IN CASH, CASH EQUIVALENTS AND RESTRICTED CASH	387.6	7.8
CASH, CASH EQUIVALENTS AND RESTRICTED CASH:
Beginning of period	160.3	3.5
End of period	$ 547.9	$ 11.3

Consolidated Statements of Ca_2

Consolidated Statements of Cash Flows (Parenthetical) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018	Mar. 31, 2018	Dec. 31, 2017
Statement of Cash Flows [Abstract]
Restricted cash	$ 414.3	$ 0	$ 0.1	$ 0.1

Consolidated Statements of Chan

Consolidated Statements of Changes in Equity - USD ($) $ in Millions	Total	Common stock	Retained earnings	Derivative Hedging Instrument	AOCI	Non-controlling interests
Beginning balance (in shares) at Dec. 31, 2017		142,094,275
Beginning balance at Dec. 31, 2017	$ 3,860.4	$ 2,734.8	$ 1,173.3		$ 0	$ (47.7)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	62.9		60.5			2.4
Issuance of stock for compensation and reinvested dividends (in shares)		138,828
Issuance of stock for compensation and reinvested dividends	(3.7)	$ (3.7)
Dividends declared on common stock	(57.7)		(57.7)
Stock compensation expense	2.5	$ 2.5
Net current period other comprehensive income	0
Ending balance (in shares) at Mar. 31, 2018		142,233,103
Ending balance at Mar. 31, 2018	3,864.4	$ 2,733.6	1,176.1		0	(45.3)
Beginning balance (in shares) at Dec. 31, 2018		255,326,252
Beginning balance at Dec. 31, 2018	9,990.7	$ 8,685.2	1,346		(3)	(37.5)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	103.4		99.5			3.9
Issuance of stock for compensation and reinvested dividends (in shares)		60,594
Issuance of stock for compensation and reinvested dividends	(1.6)	$ (1.6)
Dividends declared on common stock	(119.8)		(119.8)
Stock compensation expense	5.4	$ 5.4
Repurchase of common stock (in shares)		(10,548,060)
Repurchase of common stock under repurchase plan	(578.3)	$ (578.3)
Consolidation of noncontrolling interests	3.8					3.8
Distributions to shareholders of noncontrolling interests	(1.4)					(1.4)
Net current period other comprehensive income	(10.2)			$ (10.2)
Other	(0.3)	$ (0.3)
Ending balance (in shares) at Mar. 31, 2019		244,838,786
Ending balance at Mar. 31, 2019	$ 9,391.7	$ 8,110.4	$ 1,325.7		$ (13.2)	$ (31.2)

Consolidated Statements of Ch_2

Consolidated Statements of Changes in Equity (Parenthetical) - $ / shares	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Statement of Stockholders' Equity [Abstract]
Dividends declared on common stock (in dollars per share)	$ 0.475	$ 0.4

Consolidated Balance Sheets - W

Consolidated Balance Sheets - Westar Energy, Inc Statement - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
CURRENT ASSETS:
Cash and cash equivalents	$ 133.6	$ 160.3
Receivables, net	164.8	193.7
Accounts receivable pledged as collateral	359	365
Fuel inventory and supplies	466.5	511
Income taxes receivable	56.7	68
Regulatory assets	266.5	303.9
Prepaid expenses and other assets	66.2	79.1
Total Current Assets	1,927.6	1,681
PROPERTY, PLANT AND EQUIPMENT, NET	18,838.1	18,782.5
OTHER ASSETS:
Regulatory assets	1,731.6	1,757.9
Nuclear decommissioning trust fund	518.3	472.1
Other	535.1	396.5
Total Other Assets	5,123.9	4,965.4
TOTAL ASSETS	26,060.7	25,598.1
CURRENT LIABILITIES:
Current maturities of long-term debt	701.1	705.4
Notes payable and commercial paper	1,311	738.6
Collateralized note payable	359	365
Accounts payable	293.7	451.5
Accrued taxes	222.5	133.6
Accrued interest	150.2	110.9
Regulatory liabilities	34.5	110.2
Asset retirement obligations	52.6	49.8
Other	178.5	171.9
Total Current Liabilities	3,335.4	2,867.2
LONG-TERM LIABILITIES:
Long-term debt, net	7,125.9	6,636.3
Deferred income taxes	1,603.8	1,599.2
Unamortized investment tax credits	372.4	373.2
Regulatory liabilities	2,249.2	2,218.8
Pension and post-retirement liability	994.3	987.6
Asset retirement obligations	645.8	637.3
Other	323.4	236.7
Total Long-Term Liabilities	13,333.6	12,740.2
Commitments and Contingencies (Note 9)
Evergy, Inc. Shareholders' Equity:
Common stock	8,110.4	8,685.2
Retained earnings	1,325.7	1,346
Total Shareholders' Equity	9,422.9	10,028.2
Noncontrolling Interests	(31.2)	(37.5)
Total Equity	9,391.7	9,990.7
TOTAL LIABILITIES AND EQUITY	26,060.7	25,598.1
Westar Energy
CURRENT ASSETS:
Cash and cash equivalents	3	44.5
Receivables, net	90.4	84.3
Related party receivables	2.5	2.6
Accounts receivable pledged as collateral	185	185
Fuel inventory and supplies	255	276.8
Income taxes receivable	32	42.7
Regulatory assets	85.2	97.1
Prepaid expenses and other assets	25.6	35
Total Current Assets	678.7	768
PROPERTY, PLANT AND EQUIPMENT, NET	9,726.4	9,718.3
OTHER ASSETS:
Regulatory assets	696.4	700.4
Nuclear decommissioning trust fund	248.4	227.5
Other	291.9	233.4
Total Other Assets	1,236.7	1,161.3
TOTAL ASSETS	11,812.9	11,816.8
CURRENT LIABILITIES:
Current maturities of long-term debt	300	300
Notes payable and commercial paper	413.8	411.7
Collateralized note payable	185	185
Accounts payable	129.5	154.4
Related party payables	8.8	14.9
Accrued taxes	137.4	88.6
Accrued interest	93.2	74.4
Regulatory liabilities	15.3	19.5
Asset retirement obligations	17.1	17.1
Other	71.2	83
Total Current Liabilities	1,403.6	1,378.9
LONG-TERM LIABILITIES:
Long-term debt, net	3,390	3,389.8
Deferred income taxes	813.7	815.4
Unamortized investment tax credits	249.2	249.7
Regulatory liabilities	1,118.5	1,101.8
Pension and post-retirement liability	473.6	474.7
Asset retirement obligations	268.2	264
Other	155.9	130.7
Total Long-Term Liabilities	6,487.9	6,477.2
Commitments and Contingencies (Note 9)
Evergy, Inc. Shareholders' Equity:
Common stock	2,737.6	2,737.6
Retained earnings	1,215	1,260.6
Total Shareholders' Equity	3,952.6	3,998.2
Noncontrolling Interests	(31.2)	(37.5)
Total Equity	3,921.4	3,960.7
TOTAL LIABILITIES AND EQUITY	11,812.9	11,816.8
Variable Interest Entities
CURRENT ASSETS:
PROPERTY, PLANT AND EQUIPMENT, NET	171.1	169.2
CURRENT LIABILITIES:
Current maturities of long-term debt	32.3	30.3
LONG-TERM LIABILITIES:
Long-term debt, net	18.8	51.1
Variable Interest Entities | Westar Energy
CURRENT ASSETS:
PROPERTY, PLANT AND EQUIPMENT, NET	171.1	169.2
CURRENT LIABILITIES:
Current maturities of long-term debt	32.3	30.3
LONG-TERM LIABILITIES:
Long-term debt, net	$ 18.8	$ 51.1

Consolidated Balance Sheets -_2

Consolidated Balance Sheets - Westar Energy, Inc (Parenthetical) - $ / shares	Mar. 31, 2019	Dec. 31, 2018
Common stock - shares authorized (in shares)	600,000,000	600,000,000
Common stock - shares issued (in shares)	244,838,786	255,326,252
Westar Energy
Common stock - shares authorized (in shares)	1,000	1,000
Common stock - par value (in dollars per share)	$ 0.01	$ 0.01
Common stock - shares issued (in shares)	1	1

Consolidated Statements of Inco

Consolidated Statements of Income - Westar Energy, Inc Statement - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
OPERATING REVENUES	$ 1,216.9	$ 600.2
OPERATING EXPENSES:
Fuel and purchased power	330	135.5
SPP network transmission costs	63.5	67.6
Operating and maintenance	306.9	140.1
Depreciation and amortization	213.6	89.6
Taxes other than income tax	93.3	43.9
Total Operating Expenses	1,007.3	476.7
INCOME FROM OPERATIONS	209.6	123.5
OTHER INCOME (EXPENSE):
Investment earnings (loss)	3.2	(0.4)
Other income	8.2	2
Other expense	(19.4)	(10.6)
Total Other Income (Expense), Net	(8)	(9)
Interest expense	91.1	43.8
INCOME BEFORE INCOME TAXES	110.5	70.7
Income tax expense	9.3	9.2
Equity in earnings of equity method investees, net of income taxes	2.2	1.4
NET INCOME	103.4	62.9
Less: Net income attributable to noncontrolling interests	3.9	2.4
Net income attributable to Evergy, Inc.	99.5	60.5
Westar Energy
OPERATING REVENUES	596.8	600.2
OPERATING EXPENSES:
Fuel and purchased power	122.7	135.5
SPP network transmission costs	63.5	67.6
Operating and maintenance	128.6	140.1
Depreciation and amortization	109.8	89.6
Taxes other than income tax	47.9	43.9
Total Operating Expenses	472.5	476.7
INCOME FROM OPERATIONS	124.3	123.5
OTHER INCOME (EXPENSE):
Investment earnings (loss)	1.5	(0.4)
Other income	7.3	2
Other expense	(10.6)	(10.6)
Total Other Income (Expense), Net	(1.8)	(9)
Interest expense	44.9	43.8
INCOME BEFORE INCOME TAXES	77.6	70.7
Income tax expense	10.5	9.2
Equity in earnings of equity method investees, net of income taxes	1.2	1.4
NET INCOME	68.3	62.9
Less: Net income attributable to noncontrolling interests	3.9	2.4
Net income attributable to Evergy, Inc.	$ 64.4	$ 60.5

Consolidated Statements of Ca_3

Consolidated Statements of Cash Flows - Westar Energy Inc Statement - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
CASH FLOWS FROM (USED IN) OPERATING ACTIVITIES:
Net income	$ 103.4	$ 62.9
Adjustments to reconcile income to net cash from operating activities:
Depreciation and amortization	213.6	89.6
Amortization of nuclear fuel	14.6	7.7
Amortization of deferred refueling outage	6.5	4
Amortization of corporate-owned life insurance	6.6	5.5
Non-cash compensation	5.4	2.5
Net deferred income taxes and credits	(2)	3.8
Allowance for equity funds used during construction	(0.2)	(1.1)
Payments for asset retirement obligations	(1.2)	(1.9)
Equity in earnings of equity method investees, net of income taxes	(2.2)	(1.4)
Income from corporate-owned life insurance	(9.9)	(0.7)
Other	(1.3)	(1.4)
Changes in working capital items:
Accounts receivable	26.6	46.2
Fuel inventory and supplies	44.6	6.9
Prepaid expenses and other current assets	35.5	(0.1)
Accounts payable	(119.4)	(24.2)
Accrued taxes	100.2	48.7
Other current liabilities	(74.7)	(11.8)
Changes in other assets	12.8	0.7
Changes in other liabilities	(2.8)	23.7
Cash Flows from Operating Activities	362.1	259.6
CASH FLOWS FROM (USED IN) INVESTING ACTIVITIES:
Additions to property, plant and equipment	(309)	(174.8)
Purchase of securities - trusts	(17.9)	(85.4)
Sale of securities - trusts	15.4	86.1
Investment in corporate-owned life insurance	(2.1)	(1)
Proceeds from investment in corporate-owned life insurance	40.9	2.6
Other investing activities	1.3	(1.6)
Cash Flows used in Investing Activities	(271.4)	(174.1)
CASH FLOWS FROM (USED IN) FINANCING ACTIVITIES:
Short term debt, net	572.4	14.1
Retirements of long-term debt of variable interest entities	(30.3)	(28.5)
Borrowings against cash surrender value of corporate-owned life insurance	0.6	0.7
Repayment of borrowings against cash surrender value of corporate-owned life insurance	(30.1)	(1.7)
Cash dividends paid	(119.8)	(57.4)
Other financing activities	(4.5)	(4.9)
Cash Flows used in Financing Activities	296.9	(77.7)
NET CHANGE IN CASH, CASH EQUIVALENTS AND RESTRICTED CASH	387.6	7.8
CASH, CASH EQUIVALENTS AND RESTRICTED CASH:
Beginning of period	160.3	3.5
End of period	547.9	11.3
Westar Energy
CASH FLOWS FROM (USED IN) OPERATING ACTIVITIES:
Net income	68.3	62.9
Adjustments to reconcile income to net cash from operating activities:
Depreciation and amortization	109.8	89.6
Amortization of nuclear fuel	7.3	7.7
Amortization of deferred refueling outage	3.2	4
Amortization of corporate-owned life insurance	6.6	5.5
Non-cash compensation	0	2.5
Net deferred income taxes and credits	(0.3)	3.8
Allowance for equity funds used during construction	0	(1.1)
Payments for asset retirement obligations	(0.3)	(1.9)
Equity in earnings of equity method investees, net of income taxes	(1.2)	(1.4)
Income from corporate-owned life insurance	(9.3)	(0.7)
Other	(1.4)	(1.4)
Changes in working capital items:
Accounts receivable	(7.9)	46.2
Fuel inventory and supplies	21.9	6.9
Prepaid expenses and other current assets	14.8	(0.1)
Accounts payable	(7.2)	(24.2)
Accrued taxes	59.5	48.7
Other current liabilities	(18.9)	(11.8)
Changes in other assets	4.6	0.7
Changes in other liabilities	(7)	23.7
Cash Flows from Operating Activities	242.5	259.6
CASH FLOWS FROM (USED IN) INVESTING ACTIVITIES:
Additions to property, plant and equipment	(151.7)	(174.8)
Purchase of securities - trusts	(7.5)	(85.4)
Sale of securities - trusts	7.2	86.1
Investment in corporate-owned life insurance	(2.1)	(1)
Proceeds from investment in corporate-owned life insurance	40.3	2.6
Other investing activities	(0.1)	(1.6)
Cash Flows used in Investing Activities	(113.9)	(174.1)
CASH FLOWS FROM (USED IN) FINANCING ACTIVITIES:
Short term debt, net	2.1	14.1
Retirements of long-term debt of variable interest entities	(30.3)	(28.5)
Borrowings against cash surrender value of corporate-owned life insurance	0.6	0.7
Repayment of borrowings against cash surrender value of corporate-owned life insurance	(30.1)	(1.7)
Cash dividends paid	(110)	(57.4)
Other financing activities	(2.4)	(4.9)
Cash Flows used in Financing Activities	(170.1)	(77.7)
NET CHANGE IN CASH, CASH EQUIVALENTS AND RESTRICTED CASH	(41.5)	7.8
CASH, CASH EQUIVALENTS AND RESTRICTED CASH:
Beginning of period	44.5	3.5
End of period	$ 3	$ 11.3

Consolidated Statements of Ca_4

Consolidated Statements of Cash Flows - Westar Energy Inc (Parenthetical) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018	Mar. 31, 2018	Dec. 31, 2017
Restricted cash	$ 414.3	$ 0	$ 0.1	$ 0.1
Westar Energy
Restricted cash	$ 0	$ 0	$ 0.1	$ 0.1

Consolidated Statements of Ch_3

Consolidated Statements of Changes in Equity - Westar Energy, Inc Statement - USD ($) $ in Millions	Total	Common stock	Retained earnings	Non-controlling interests	Westar Energy	Westar EnergyCommon stock	Westar EnergyRetained earnings	Westar EnergyNon-controlling interests
Beginning balance (in shares) at Dec. 31, 2017		142,094,275				142,094,275
Beginning balance at Dec. 31, 2017	$ 3,860.4	$ 2,734.8	$ 1,173.3	$ (47.7)	$ 3,860.4	$ 2,734.8	$ 1,173.3	$ (47.7)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	62.9		60.5	2.4	62.9		60.5	2.4
Issuance of stock for compensation and reinvested dividends (in shares)		138,828				138,828
Issuance of stock for compensation and reinvested dividends	(3.7)	$ (3.7)			(3.7)	$ (3.7)
Dividends declared on common stock	(57.7)		(57.7)		(57.7)		(57.7)
Stock compensation expense	2.5	$ 2.5			2.5	$ 2.5
Ending balance (in shares) at Mar. 31, 2018		142,233,103				142,233,103
Ending balance at Mar. 31, 2018	3,864.4	$ 2,733.6	1,176.1	(45.3)	3,864.4	$ 2,733.6	1,176.1	(45.3)
Beginning balance (in shares) at Dec. 31, 2018		255,326,252				1
Beginning balance at Dec. 31, 2018	9,990.7	$ 8,685.2	1,346	(37.5)	3,960.7	$ 2,737.6	1,260.6	(37.5)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	103.4		99.5	3.9	68.3		64.4	3.9
Issuance of stock for compensation and reinvested dividends (in shares)		60,594
Issuance of stock for compensation and reinvested dividends	(1.6)	$ (1.6)
Dividends declared on common stock	(119.8)		(119.8)		(110)		(110)
Stock compensation expense	5.4	$ 5.4
Consolidation of noncontrolling interests	3.8			3.8	3.8			3.8
Distributions to shareholders of noncontrolling interests	(1.4)			(1.4)	(1.4)			(1.4)
Ending balance (in shares) at Mar. 31, 2019		244,838,786				1
Ending balance at Mar. 31, 2019	$ 9,391.7	$ 8,110.4	$ 1,325.7	$ (31.2)	$ 3,921.4	$ 2,737.6	$ 1,215	$ (31.2)

Consolidated Balance Sheets - K

Consolidated Balance Sheets - Kansas City Power & Light Company Statement - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
CURRENT ASSETS:
Cash and cash equivalents	$ 133.6	$ 160.3
Restricted cash	414.3	0
Receivables, net	164.8	193.7
Accounts receivable pledged as collateral	359	365
Fuel inventory and supplies	466.5	511
Regulatory assets	266.5	303.9
Prepaid expenses and other assets	66.2	79.1
Total Current Assets	1,927.6	1,681
PROPERTY, PLANT AND EQUIPMENT, NET	18,838.1	18,782.5
OTHER ASSETS:
Regulatory assets	1,731.6	1,757.9
Nuclear decommissioning trust fund	518.3	472.1
Other	535.1	396.5
Total Other Assets	5,123.9	4,965.4
TOTAL ASSETS	26,060.7	25,598.1
CURRENT LIABILITIES:
Current maturities of long-term debt	701.1	705.4
Notes payable and commercial paper	1,311	738.6
Collateralized note payable	359	365
Accounts payable	293.7	451.5
Accrued taxes	222.5	133.6
Accrued interest	150.2	110.9
Regulatory liabilities	34.5	110.2
Asset retirement obligations	52.6	49.8
Other	178.5	171.9
Total Current Liabilities	3,335.4	2,867.2
LONG-TERM LIABILITIES:
Long-term debt, net	7,125.9	6,636.3
Deferred income taxes	1,603.8	1,599.2
Unamortized investment tax credits	372.4	373.2
Regulatory liabilities	2,249.2	2,218.8
Pension and post-retirement liability	994.3	987.6
Asset retirement obligations	645.8	637.3
Other	323.4	236.7
Total Long-Term Liabilities	13,333.6	12,740.2
Commitments and Contingencies (Note 9)
Evergy, Inc. Shareholders' Equity:
Common stock	8,110.4	8,685.2
Retained earnings	1,325.7	1,346
Accumulated other comprehensive loss	(13.2)	(3)
Total Shareholders' Equity	9,422.9	10,028.2
TOTAL LIABILITIES AND EQUITY	26,060.7	25,598.1
KCP&L
CURRENT ASSETS:
Cash and cash equivalents	2.8	2.6
Restricted cash	414.3	0
Receivables, net	41.8	62.7
Related party receivables	81.2	101.8
Accounts receivable pledged as collateral	124	130
Fuel inventory and supplies	159.3	177.6
Regulatory assets	111.4	130.9
Prepaid expenses and other assets	35	36.9
Total Current Assets	969.8	642.5
PROPERTY, PLANT AND EQUIPMENT, NET	6,714.1	6,688.1
OTHER ASSETS:
Regulatory assets	471.2	495.2
Nuclear decommissioning trust fund	269.9	244.6
Other	140.1	50.1
Total Other Assets	881.2	789.9
TOTAL ASSETS	8,565.1	8,120.5
CURRENT LIABILITIES:
Current maturities of long-term debt	400	400
Notes payable and commercial paper	176	176.9
Collateralized note payable	124	130
Accounts payable	131.2	211.1
Accrued taxes	77.1	39.7
Accrued interest	41.1	28.9
Regulatory liabilities	8.1	52.8
Asset retirement obligations	29.7	29.2
Other	75.6	69.7
Total Current Liabilities	1,062.8	1,138.3
LONG-TERM LIABILITIES:
Long-term debt, net	2,524.6	2,130.1
Deferred income taxes	636.4	631.8
Unamortized investment tax credits	120.4	120.7
Regulatory liabilities	809.9	794.3
Pension and post-retirement liability	500.1	491.9
Asset retirement obligations	237.7	231.8
Other	156.5	81.8
Total Long-Term Liabilities	4,985.6	4,482.4
Commitments and Contingencies (Note 9)
Evergy, Inc. Shareholders' Equity:
Common stock	1,563.1	1,563.1
Retained earnings	948.6	932.6
Accumulated other comprehensive loss	5	4.1
Total Shareholders' Equity	2,516.7	2,499.8
TOTAL LIABILITIES AND EQUITY	$ 8,565.1	$ 8,120.5

Consolidated Balance Sheets -_3

Consolidated Balance Sheets - Kansas City Power & Light Company (Parenthetical) - shares	Mar. 31, 2019	Dec. 31, 2018
Common stock - shares authorized (in shares)	600,000,000	600,000,000
Common stock - shares issued (in shares)	244,838,786	255,326,252
KCP&L
Common stock - shares authorized (in shares)	1,000	1,000
Common stock - shares issued (in shares)	1	1

Consolidated Statements of Co_2

Consolidated Statements of Comprehensive Income - Kansas City Power & Light Company Statement - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
OPERATING REVENUES	$ 1,216.9	$ 600.2
OPERATING EXPENSES:
Fuel and purchased power	330	135.5
Operating and maintenance	306.9	140.1
Depreciation and amortization	213.6	89.6
Taxes other than income tax	93.3	43.9
Total Operating Expenses	1,007.3	476.7
INCOME FROM OPERATIONS	209.6	123.5
OTHER INCOME (EXPENSE):
Investment earnings (loss)	3.2	(0.4)
Other income	8.2	2
Other expense	(19.4)	(10.6)
Total Other Income (Expense), Net	(8)	(9)
Interest expense	91.1	43.8
INCOME BEFORE INCOME TAXES	110.5	70.7
Income tax expense	9.3	9.2
Net income attributable to Evergy, Inc.	99.5	60.5
OTHER COMPREHENSIVE INCOME:
Derivative hedging activity, net of tax	(10.2)	0
COMPREHENSIVE INCOME	89.3	60.5
KCP&L
OPERATING REVENUES	425.4	397.1
OPERATING EXPENSES:
Fuel and purchased power	134.9	117.5
Operating and maintenance	122	122.7
Depreciation and amortization	78.9	66.9
Taxes other than income tax	32.7	29
Total Operating Expenses	368.5	336.1
INCOME FROM OPERATIONS	56.9	61
OTHER INCOME (EXPENSE):
Investment earnings (loss)	0.8	0.6
Other income	0.8	3
Other expense	(5)	(7.9)
Total Other Income (Expense), Net	(3.4)	(4.3)
Interest expense	33.8	33
INCOME BEFORE INCOME TAXES	19.7	23.7
Income tax expense	3.7	3.5
Net income attributable to Evergy, Inc.	16	20.2
OTHER COMPREHENSIVE INCOME:
Reclassification to expenses, net of tax	0.9	0.9
Derivative hedging activity, net of tax	0.9	0.9
Total other comprehensive loss	0.9	0.9
COMPREHENSIVE INCOME	$ 16.9	$ 21.1

Consolidated Statements of Ca_5

Consolidated Statements of Cash Flows - Kansas City Power & Light Company Statement - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
CASH FLOWS FROM (USED IN) OPERATING ACTIVITIES:
Net income	$ 103.4	$ 62.9
Adjustments to reconcile income to net cash from operating activities:
Depreciation and amortization	213.6	89.6
Amortization of nuclear fuel	14.6	7.7
Amortization of deferred refueling outage	6.5	4
Net deferred income taxes and credits	(2)	3.8
Allowance for equity funds used during construction	(0.2)	(1.1)
Payments for asset retirement obligations	(1.2)	(1.9)
Other	(1.3)	(1.4)
Changes in working capital items:
Accounts receivable	26.6	46.2
Accounts receivable pledged as collateral	6	0
Fuel inventory and supplies	44.6	6.9
Prepaid expenses and other current assets	35.5	(0.1)
Accounts payable	(119.4)	(24.2)
Accrued taxes	100.2	48.7
Other current liabilities	(74.7)	(11.8)
Changes in other assets	12.8	0.7
Changes in other liabilities	(2.8)	23.7
Cash Flows from Operating Activities	362.1	259.6
CASH FLOWS FROM (USED IN) INVESTING ACTIVITIES:
Additions to property, plant and equipment	(309)	(174.8)
Purchase of securities - trusts	(17.9)	(85.4)
Sale of securities - trusts	15.4	86.1
Other investing activities	1.3	(1.6)
Cash Flows used in Investing Activities	(271.4)	(174.1)
CASH FLOWS FROM (USED IN) FINANCING ACTIVITIES:
Short term debt, net	572.4	14.1
Collateralized short-term borrowings, net	(6)	0
Proceeds from long-term debt	494	0
Retirements of long-term debt	(1.1)	0
Cash dividends paid	(119.8)	(57.4)
Cash Flows used in Financing Activities	296.9	(77.7)
NET CHANGE IN CASH, CASH EQUIVALENTS AND RESTRICTED CASH	387.6	7.8
CASH, CASH EQUIVALENTS AND RESTRICTED CASH:
Beginning of period	160.3	3.5
End of period	547.9	11.3
KCP&L
CASH FLOWS FROM (USED IN) OPERATING ACTIVITIES:
Net income	16	20.2
Adjustments to reconcile income to net cash from operating activities:
Depreciation and amortization	78.9	66.9
Amortization of nuclear fuel	7.4	7.7
Amortization of deferred refueling outage	3.2	3.9
Net deferred income taxes and credits	(5)	5.3
Allowance for equity funds used during construction	(0.2)	(1.4)
Payments for asset retirement obligations	(0.8)	(3.6)
Other	0.6	0.2
Changes in working capital items:
Accounts receivable	41.9	47.9
Accounts receivable pledged as collateral	6	0
Fuel inventory and supplies	18.3	(2.8)
Prepaid expenses and other current assets	19.2	(2.5)
Accounts payable	(66.8)	(90)
Accrued taxes	37.4	25
Other current liabilities	(31.9)	(1.8)
Changes in other assets	8.9	16.5
Changes in other liabilities	9.2	13.5
Cash Flows from Operating Activities	142.3	105
CASH FLOWS FROM (USED IN) INVESTING ACTIVITIES:
Additions to property, plant and equipment	(114.7)	(100.6)
Purchase of securities - trusts	(10.3)	(12.1)
Sale of securities - trusts	8.2	11.3
Other investing activities	1.9	0.6
Cash Flows used in Investing Activities	(114.9)	(100.8)
CASH FLOWS FROM (USED IN) FINANCING ACTIVITIES:
Short term debt, net	(0.9)	120.8
Collateralized short-term borrowings, net	(6)	0
Proceeds from long-term debt	394	296.6
Retirements of long-term debt	0	(350)
Cash dividends paid	0	(60)
Cash Flows used in Financing Activities	387.1	7.4
NET CHANGE IN CASH, CASH EQUIVALENTS AND RESTRICTED CASH	414.5	11.6
CASH, CASH EQUIVALENTS AND RESTRICTED CASH:
Beginning of period	2.6	2.2
End of period	$ 417.1	$ 13.8

Consolidated Statements of Ca_6

Consolidated Statements of Cash Flows - Kansas City Power & Light Company (Parenthetical) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018	Mar. 31, 2018	Dec. 31, 2017
Restricted cash	$ 414.3	$ 0	$ 0.1	$ 0.1
KCP&L
Restricted cash	$ 414.3	$ 0	$ 0	$ 0

Consolidated Statements of Ch_4

Consolidated Statements of Changes in Equity - Kansas City Power & Light Company Statement - USD ($) $ in Millions	Total	Common stock	Retained earnings	Derivative Hedging Instrument	AOCI - Net gains (losses) on cash flow hedges	KCP&L	KCP&LCommon stock	KCP&LRetained earnings	KCP&LDerivative Hedging Instrument	KCP&LAOCI - Net gains (losses) on cash flow hedges
Beginning balance (in shares) at Dec. 31, 2017		142,094,275					1
Beginning balance at Dec. 31, 2017	$ 3,860.4	$ 2,734.8	$ 1,173.3		$ 0	$ 2,513.2	$ 1,563.1	$ 949.7		$ 0.4
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	62.9		60.5			20.2		20.2
Dividends declared on common stock	(57.7)		(57.7)			(60)		(60)
Net current period other comprehensive income	0					0.9			$ 0.9
Ending balance (in shares) at Mar. 31, 2018		142,233,103					1
Ending balance at Mar. 31, 2018	3,864.4	$ 2,733.6	1,176.1		0	2,474.3	$ 1,563.1	909.9		1.3
Beginning balance (in shares) at Dec. 31, 2018		255,326,252					1
Beginning balance at Dec. 31, 2018	9,990.7	$ 8,685.2	1,346		(3)	2,499.8	$ 1,563.1	932.6		4.1
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	103.4		99.5			16		16
Dividends declared on common stock	(119.8)		(119.8)
Net current period other comprehensive income	(10.2)			$ (10.2)		0.9			$ 0.9
Ending balance (in shares) at Mar. 31, 2019		244,838,786					1
Ending balance at Mar. 31, 2019	$ 9,391.7	$ 8,110.4	$ 1,325.7		$ (13.2)	$ 2,516.7	$ 1,563.1	$ 948.6		$ 5

ORGANIZATION AND BASIS OF PRESE

ORGANIZATION AND BASIS OF PRESENTATION	3 Months Ended
	Mar. 31, 2019
Accounting Policies [Abstract]
ORGANIZATION AND BASIS OF PRESENTATION	ORGANIZATION AND BASIS OF PRESENTATION Organization Evergy is a public utility holding company incorporated in 2017 and headquartered in Kansas City, Missouri. Evergy operates primarily through the following wholly-owned direct subsidiaries: • Westar Energy is an integrated, regulated electric utility that provides electricity to customers in the state of Kansas. Westar Energy has one active wholly-owned subsidiary with significant operations, Kansas Gas and Electric Company (KGE). • KCP&L is an integrated, regulated electric utility that provides electricity to customers in the states of Missouri and Kansas. • KCP&L Greater Missouri Operations Company (GMO) is an integrated, regulated electric utility that provides electricity to customers in the state of Missouri. • GPE Transmission Holding Company, LLC (GPETHC) owns 13.5% of Transource Energy, LLC (Transource) with the remaining 86.5% owned by AEP Transmission Holding Company, LLC, a subsidiary of American Electric Power Company, Inc. (AEP). Transource is focused on the development of competitive electric transmission projects. GPETHC accounts for its investment in Transource under the equity method. Westar Energy also owns a 50% interest in Prairie Wind Transmission, LLC (Prairie Wind), which is a joint venture between Westar Energy and affiliates of AEP and Berkshire Hathaway Energy Company. Prairie Wind owns a 108 -mile, 345 kV double-circuit transmission line that provides transmission service in the Southwest Power Pool, Inc. (SPP). Westar Energy accounts for its investment in Prairie Wind under the equity method. Westar Energy and KGE conduct business in their respective service territories using the name Westar Energy. KCP&L and GMO conduct business in their respective service territories using the name KCP&L. Collectively, the Evergy Companies have approximately 14,500 MWs of owned generating capacity and renewable purchased power agreements and engage in the generation, transmission, distribution and sale of electricity to approximately 1.6 million customers in the states of Kansas and Missouri. Evergy was incorporated in 2017 as Monarch Energy Holding, Inc. (Monarch Energy), a wholly-owned subsidiary of Great Plains Energy Incorporated (Great Plains Energy). Prior to the closing of the merger transactions, Monarch Energy changed its name to Evergy and did not conduct any business activities other than those required for its formation and matters contemplated by the Amended and Restated Agreement and Plan of Merger, dated as of July 9, 2017, by and among Great Plains Energy, Westar Energy, Monarch Energy and King Energy, Inc. (King Energy), a wholly-owned subsidiary of Monarch Energy (Amended Merger Agreement). On June 4, 2018, in accordance with the Amended Merger Agreement, Great Plains Energy merged into Evergy, with Evergy surviving the merger and King Energy merged into Westar Energy, with Westar Energy surviving the merger. These merger transactions resulted in Evergy becoming the parent entity of Westar Energy and the direct subsidiaries of Great Plains Energy, including KCP&L and GMO. As a result of the closing of the merger transactions, each outstanding share of Great Plains Energy common stock was converted into 0.5981 shares of Evergy common stock, resulting in the issuance of 128.9 million shares. Additionally, each outstanding share of Westar Energy common stock was converted into 1 share of Evergy common stock. Principles of Consolidation Westar Energy was determined to be the accounting acquirer in the merger and thus, the predecessor of Evergy. Therefore, Evergy's consolidated financial statements reflect the results of operations of Westar Energy for the three months ended March 31, 2018. Evergy had separate operations for the period beginning with the quarter ended June 30, 2018, and references to amounts for periods after the closing of the merger relate to Evergy. The results of Great Plains Energy's direct subsidiaries have been included in Evergy's results of operations from the date of the closing of the merger and thereafter. Each of Evergy's, Westar Energy's and KCP&L's consolidated financial statements includes the accounts of their subsidiaries and variable interest entities (VIEs) of which they are the primary beneficiary. Undivided interests in jointly-owned generation facilities are included on a proportionate basis. Intercompany transactions have been eliminated. The Evergy Companies assess financial performance and allocate resources on a consolidated basis (i.e., operate in one segment). Certain changes in classification and corresponding reclassification of prior period data were made in Evergy's, Westar Energy's and KCP&L's unaudited consolidated statements of income and comprehensive income and unaudited statements of cash flows for comparative purposes. Evergy reflects the classifications of Westar Energy as the accounting acquirer in the merger. These reclassifications did not affect Evergy's, Westar Energy's or KCP&L's net income or Evergy's, Westar Energy's or KCP&L's cash flows from operations, investing or financing. The table below summarizes KCP&L's reclassifications related to operating and investing activities for its consolidated statement of cash flows for the three months ended March 31, 2018 . As Previously Filed As Recast CASH FLOWS FROM (USED IN) OPERATING ACTIVITIES: (millions) Adjustments to reconcile income to net cash from operating activities: Amortization of other $ 6.6 $ — Amortization of deferred refueling outage — 3.9 Deferred income taxes, net 5.6 — Investment tax credit amortization (0.3 ) — Net deferred income taxes and credits — 5.3 Other (a) 3.8 0.2 Changes in working capital items: Fuel inventory and supplies — (2.8 ) Fuel inventories (a) (1.0 ) — Materials and supplies (a) (1.8 ) — Prepaid expenses and other current assets — (2.5 ) Accrued interest (a) 8.3 — Other current liabilities — (1.8 ) Changes in other assets — 16.5 Changes in other liabilities — 13.5 Deferred refueling outage costs (a) 0.9 — Pension and post-retirement benefit obligations (a) 9.0 — Fuel recovery mechanisms (a) 1.2 — Total reclassifications $ 32.3 $ 32.3 CASH FLOWS FROM (USED IN) INVESTING ACTIVITIES: Additions to property, plant and equipment $ — $ (100.6 ) Utility capital expenditures (93.5 ) — Allowance for borrowed funds used during construction (2.0 ) — Other investing activities (4.5 ) 0.6 Total reclassifications $ (100.0 ) $ (100.0 ) (a) Previously reported within Note 4 to the consolidated financial statements of the Great Plains Energy and KCP&L combined First Quarter 2018 Quarterly Report on Form 10-Q. Restricted Cash As of March 31, 2019, Evergy and KCP&L had restricted cash balances of $414.3 million as a result of the net proceeds from KCP&L's issuance of $400.0 million of 4.125% Mortgage Bonds in March 2019 that were irrevocably deposited with a bond trustee along with accrued interest, in order to retire KCP&L's 7.15% Mortgage Bonds, which matured in April 2019. See Note 7 for additional details. Fuel Inventory and Supplies The Evergy Companies record fuel inventory and supplies at average cost. The following table separately states the balances for fuel inventory and supplies. March 31 December 31 2019 2018 Evergy (millions) Fuel inventory $ 132.2 $ 168.9 Supplies 334.3 342.1 Fuel inventory and supplies $ 466.5 $ 511.0 Westar Energy Fuel inventory $ 74.2 $ 87.8 Supplies 180.8 189.0 Fuel inventory and supplies $ 255.0 $ 276.8 KCP&L Fuel inventory $ 39.2 $ 57.8 Supplies 120.1 119.8 Fuel inventory and supplies $ 159.3 $ 177.6 Property, Plant and Equipment The following tables summarize the property, plant and equipment of Evergy, Westar Energy and KCP&L. March 31, 2019 Evergy Westar Energy KCP&L (millions) Electric plant in service $ 27,161.1 $ 13,263.5 $ 10,546.0 Electric plant acquisition adjustment 740.6 740.6 — Accumulated depreciation (9,856.2 ) (4,721.2 ) (4,083.5 ) Plant in service 18,045.5 9,282.9 6,462.5 Construction work in progress 635.7 365.0 173.2 Nuclear fuel, net 155.9 77.5 78.4 Plant to be retired, net (a) 1.0 1.0 — Property, plant and equipment, net $ 18,838.1 $ 9,726.4 $ 6,714.1 December 31, 2018 Evergy Westar Energy KCP&L (millions) Electric plant in service $ 26,916.7 $ 13,176.7 $ 10,439.1 Electric plant acquisition adjustment 740.6 740.6 — Accumulated depreciation (9,694.1 ) (4,642.8 ) (4,022.4 ) Plant in service 17,963.2 9,274.5 6,416.7 Construction work in progress 685.2 376.7 204.4 Nuclear fuel, net 133.1 66.1 67.0 Plant to be retired, net (a) 1.0 1.0 — Property, plant and equipment, net $ 18,782.5 $ 9,718.3 $ 6,688.1 (a) As of March 31, 2019 and December 31, 2018 , represents the planned retirement of Westar Energy analog meters prior to the end of their remaining useful lives. Other Income (Expense), Net The table below shows the detail of other expense for each of the Evergy Companies. Three Months Ended March 31 2019 2018 Evergy (millions) Non-service cost component of net benefit cost $ (13.1 ) $ (5.7 ) Other (6.3 ) (4.9 ) Other expense $ (19.4 ) $ (10.6 ) Westar Energy Non-service cost component of net benefit cost $ (4.4 ) $ (5.7 ) Other (6.2 ) (4.9 ) Other expense $ (10.6 ) $ (10.6 ) KCP&L (a) Non-service cost component of net benefit cost $ (5.1 ) $ (6.7 ) Other 0.1 (1.2 ) Other expense $ (5.0 ) $ (7.9 ) (a) KCP&L amounts are not included in consolidated Evergy for the three months ended March 31, 2018. Earnings Per Share To compute basic earnings per share (EPS), Evergy divides net income attributable to Evergy, Inc. by the weighted average number of common shares outstanding. Diluted EPS includes the effect of issuable common shares resulting from restricted share units (RSUs), performance shares and restricted stock. Evergy computes the dilutive effects of potential issuances of common shares using the treasury stock method. The following table reconciles Evergy's basic and diluted EPS. Three Months Ended March 31 2019 2018 Income (millions, except per share amounts) Net income $ 103.4 $ 62.9 Less: net income attributable to noncontrolling interests 3.9 2.4 Net income attributable to Evergy, Inc. 99.5 60.5 Common Shares Outstanding Weighted average number of common shares outstanding - basic 252.8 142.6 Add: effect of dilutive securities 0.2 0.1 Weighted average number of common shares outstanding - dilutive 253.0 142.7 Basic and Diluted EPS $ 0.39 $ 0.42 There were no anti-dilutive securities excluded from the computation of diluted EPS for the three months ended March 31, 2019 and 2018. Dividends Declared In May 2019 , Evergy's Board of Directors (Evergy Board) declared a quarterly dividend of $0.475 per share on Evergy's common stock. The common dividend is payable June 20, 2019 , to shareholders of record as of May 30, 2019 . In May 2019 , KCP&L's Board of Directors declared a cash dividend payable to Evergy of $65.0 million , payable no later than June 19, 2019 . Supplemental Cash Flow Information Three Months Ended March 31 2019 2018 Evergy (millions) Cash paid for (received from): Interest, net of amounts capitalized $ 59.3 $ 33.0 Interest of VIEs 1.0 1.3 Income taxes, net of refunds (0.1 ) (0.2 ) Non-cash investing transactions: Property, plant and equipment additions 47.1 29.8 Non-cash financing transactions: Issuance of stock for compensation and reinvested dividends 0.5 0.1 Westar Energy Cash paid for (received from): Interest, net of amounts capitalized $ 32.6 $ 33.0 Interest of VIEs 1.0 1.3 Income taxes, net of refunds — (0.2 ) Non-cash investing transactions: Property, plant and equipment additions 27.1 29.8 Non-cash financing transactions: Issuance of stock for compensation and reinvested dividends — 0.1 KCP&L (a) Cash paid for (received from): Interest, net of amounts capitalized $ 19.6 $ 22.7 Non-cash investing transactions: Property, plant and equipment additions 15.9 20.9 (a) KCP&L amounts are not included in consolidated Evergy for the three months ended March 31, 2018. See Note 13 for supplemental cash flow information regarding the Evergy Companies' leases. New Accounting Standards Intangibles - Internal-Use Software In August 2018, the Financial Accounting Standards Board (FASB) issued Accounting Standards Update (ASU) No. 2018-15, Customer's Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract , which aligns the requirements for recording implementation costs incurred in a hosting arrangement that is a service contract with the requirements for capitalizing implementation costs incurred to develop or obtain internal-use software. An entity in a hosting arrangement that is a service contract will need to determine which project stage (that is, preliminary project stage, application development stage or post-implementation stage) an implementation activity relates. Costs for implementation activities in the application development stage are recorded as a prepaid asset depending on the nature of the costs, while costs incurred during the preliminary project and post-implementation stages are expensed as the activities occur. Costs that are recorded to a prepaid asset are to be expensed over the term of the hosting arrangement. The new guidance is effective for annual periods beginning after December 15, 2019 and interim periods within those fiscal years. The new guidance can be applied either retrospectively or prospectively to all implementation costs incurred after the date of adoption. Early adoption is permitted. The Evergy Companies early adopted ASU No. 2018-15 prospectively as of January 1, 2019. The adoption of ASU No. 2018-15 did not have a material impact on the Evergy Companies. Leases In February 2016, the FASB issued ASU No. 2016-02, Leases , which requires an entity that is a lessee to record a right-of-use asset and a lease liability for lease payments on the balance sheet for all leases with terms longer than 12 months. Leases will be classified as either finance or operating, with classification affecting the pattern of expense recognition in the income statement. Lessor accounting remains largely unchanged. In January 2018, the FASB issued ASU No. 2018-01, Leases: Land Easement Practical Expedient for Transition to Topic 842 , which permits entities to elect an optional transition practical expedient to not evaluate, under Topic 842, land easements that exist or expired before the entity's adoption of Topic 842 and that were not previously accounted for as leases under Topic 840. In July 2018, the FASB issued ASU No. 2018-10, Codification Improvements to Topic 842, Leases , which updates narrow aspects of the guidance issued in ASU No. 2016-02. Also in July 2018, the FASB issued ASU No. 2018-11, Leases: Targeted Improvements , which provides an optional transition method that allows entities to initially apply Topic 842 at the adoption date and recognize a cumulative-effect adjustment to the opening balance of retained earnings in the period of adoption without restating prior periods. In December 2018, the FASB issued ASU No. 2018-20, Leases: Narrow-Scope Improvements for Lessors , which is expected to reduce a lessor's implementation and ongoing costs associated with applying ASU No. 2016-02. In March 2019, the FASB issued ASU No. 2019-01, Leases: Codification Improvements , which clarifies certain lessor accounting and interim reporting requirements. ASU No. 2016-02 and the subsequent amendments are effective for interim and annual periods beginning after December 15, 2018, with early adoption permitted, and requires a modified retrospective transition approach with an option to either adjust or not adjust comparative periods. The Evergy Companies adopted the new guidance on January 1, 2019, without adjusting comparative periods for all leases existing as of January 1, 2019, by electing the optional transition method permitted by ASU No. 2018-11. As a result, Evergy, Westar Energy and KCP&L recorded an increase to assets and liabilities of approximately $110 million , $40 million and $80 million , respectively, as of January 1, 2019. Westar Energy and KCP&L have certain lease transactions between them for which the related assets and liabilities are eliminated at consolidated Evergy. The adoption of Topic 842 did not have a material impact on the Evergy Companies' consolidated statements of income and comprehensive income and there was no cumulative-effect adjustment recorded to the opening balance of retained earnings. The Evergy Companies also elected a practical expedient to forgo reassessing existing or expired contracts as leases to determine whether each is in scope of Topic 842 and to forgo reassessing lease classification for existing and expired leases. See Note 13 for additional disclosures about the Evergy Companies' leases. Merger Pro Forma Financial Information The following unaudited pro forma financial information reflects the consolidated results of operations of Evergy as if the merger transactions had taken place on January 1, 2017. The unaudited pro forma information was calculated after applying Evergy's accounting policies and adjusting Great Plains Energy's results to reflect purchase accounting adjustments. The unaudited pro forma financial information has been presented for illustrative purposes only and is not necessarily indicative of the consolidated results of operations that would have been achieved or the future consolidated results of operations of Evergy. Three Months Ended March 31, 2018 (millions, except per share amounts) Operating revenues $ 1,184.1 Net income attributable to Evergy, Inc. 91.9 Basic earnings per common share $ 0.34 Diluted earnings per common share $ 0.34 Evergy, Westar Energy and Great Plains Energy incurred non-recurring costs and a gain directly related to the merger that have been excluded in the pro forma earnings presented above in accordance with generally accepted accounting principles (GAAP). On an after-tax basis, these non-recurring merger-related costs and gain incurred by Evergy, Westar Energy and Great Plains Energy included $5.2 million for the three months ended March 31, 2018, of after-tax mark-to-market gains on interest rate swaps for which cash settlement was contingent upon the consummation of the merger.

REVENUE

REVENUE	3 Months Ended
	Mar. 31, 2019
Revenue from Contract with Customer [Abstract]
REVENUE	REVENUE Evergy's, Westar Energy's and KCP&L's revenues disaggregated by customer class are summarized in the following tables. Three Months Ended March 31, 2019 Evergy Westar Energy KCP&L Revenues (millions) Residential $ 451.7 $ 192.3 $ 164.2 Commercial 413.5 164.3 183.8 Industrial 147.0 98.4 29.7 Other retail 9.8 5.1 2.6 Total electric retail $ 1,022.0 $ 460.1 $ 380.3 Wholesale 83.1 61.3 18.1 Transmission 76.7 69.2 3.1 Industrial steam and other 3.3 1.7 1.4 Total revenue from contracts with customers $ 1,185.1 $ 592.3 $ 402.9 Other 31.8 4.5 22.5 Operating revenues $ 1,216.9 $ 596.8 $ 425.4 Three Months Ended March 31, 2018 Evergy Westar Energy KCP&L (a) Revenues (millions) Residential $ 180.3 $ 180.3 $ 154.9 Commercial 155.4 155.4 181.8 Industrial 93.5 93.5 32.2 Other retail 4.2 4.2 2.7 Total electric retail $ 433.4 $ 433.4 $ 371.6 Wholesale 94.2 94.2 3.1 Transmission 71.9 71.9 3.3 Other 1.8 1.8 — Total revenue from contracts with customers $ 601.3 $ 601.3 $ 378.0 Other (1.1 ) (1.1 ) 19.1 Operating revenues $ 600.2 $ 600.2 $ 397.1 (a) KCP&L amounts are not included in consolidated Evergy for the three months ended March 31, 2018.

RECEIVABLES

RECEIVABLES	3 Months Ended
	Mar. 31, 2019
Receivables [Abstract]
RECEIVABLES	3 . RECEIVABLES The Evergy Companies' receivables are detailed in the following table. March 31 December 31 2019 2018 Evergy (millions) Customer accounts receivable - billed $ 15.0 $ 16.7 Customer accounts receivable - unbilled 82.1 91.2 Other receivables 77.5 95.0 Allowance for doubtful accounts (9.8 ) (9.2 ) Total $ 164.8 $ 193.7 Westar Energy Customer accounts receivable - billed $ — $ — Customer accounts receivable - unbilled 33.4 16.6 Other receivables 61.2 71.6 Allowance for doubtful accounts (4.2 ) (3.9 ) Total $ 90.4 $ 84.3 KCP&L Customer accounts receivable - billed $ 8.0 $ 7.8 Customer accounts receivable - unbilled 25.9 42.9 Other receivables 11.9 15.8 Allowance for doubtful accounts (4.0 ) (3.8 ) Total $ 41.8 $ 62.7 Evergy's, Westar Energy's and KCP&L's other receivables at March 31, 2019 and December 31, 2018 , consisted primarily of receivables from partners in jointly-owned electric utility plants and wholesale sales receivables. As of March 31, 2019 , other receivables for Evergy, Westar Energy and KCP&L included receivables from contracts with customers of $39.6 million , $36.8 million and $1.0 million , respectively. As of December 31, 2018 , other receivables for Evergy, Westar Energy and KCP&L included receivables from contracts with customers of $65.8 million , $55.9 million and $5.5 million , respectively. The Evergy Companies recorded bad debt expense related to contracts with customers as summarized in the following table. Three Months Ended March 31 2019 2018 (millions) Evergy $ 4.0 $ 4.0 Westar Energy (0.3 ) 4.0 KCP&L (a) 2.8 1.7 (a) KCP&L amounts are not included in consolidated Evergy for the three months ended March 31, 2018. Sale of Accounts Receivable Westar Energy, KCP&L and GMO sell an undivided percentage ownership interest in their retail electric and certain other accounts receivable to independent outside investors. These sales of the undivided percentage ownership interests in accounts receivable to independent outside investors are accounted for as secured borrowings with accounts receivable pledged as collateral and a corresponding short-term collateralized note payable recognized on the balance sheets. At March 31, 2019 and December 31, 2018 , Evergy's accounts receivable pledged as collateral and the corresponding short-term collateralized note payable were $359.0 million and $365.0 million , respectively. At March 31, 2019 and December 31, 2018 , Westar Energy's accounts receivable pledged as collateral and the corresponding short-term collateralized note payable were $185.0 million . At March 31, 2019 and December 31, 2018 , KCP&L's accounts receivable pledged as collateral and the corresponding short-term collateralized note payable were $124.0 million and $130.0 million , respectively. Westar Energy's receivable sale facility expires in September 2019 and allows for $185.0 million in aggregate outstanding principal amount of borrowings from mid-December through mid-January, $125.0 million from mid- January through mid-February, $185.0 million from mid-February to mid-July and then $200.0 million from mid-July through the expiration date of the facility. KCP&L's receivable sale facility expires in September 2019 and allows for $130.0 million in aggregate outstanding principal amount of borrowings at any time. GMO's receivable sale facility expires in September 2019 and allows for $50.0 million in aggregate outstanding principal amount of borrowings from mid-November through mid-June and then $65.0 million from mid-June through the expiration date of the facility.

RATE MATTERS AND REGULATION

RATE MATTERS AND REGULATION	3 Months Ended
	Mar. 31, 2019
Regulated Operations [Abstract]
RATE MATTERS AND REGULATION	RATE MATTERS AND REGULATION KCC Proceedings Westar Energy 2019 Transmission Delivery Charge In March 2019, the State Corporation Commission of the State of Kansas (KCC) issued an order adjusting Westar Energy's retail prices to include updated transmission costs as reflected in the Federal Energy Regulatory Commission (FERC) transmission formula rate (TFR). The new prices were effective in April 2019 and are expected to decrease Westar Energy's annual retail revenues by $7.7 million . KCP&L 2019 Transmission Delivery Charge In April 2019, the KCC issued an order adjusting KCP&L's retail prices to include updated transmission costs as reflected in the FERC TFR. The new prices were effective in May 2019 and are expected to decrease KCP&L's annual retail revenues by $8.3 million . Westar Energy and KCP&L Earnings Review and Sharing Plan (ERSP) As part of their merger settlement agreement with the KCC, Westar Energy and KCP&L agreed to participate in an ERSP for the years 2019 through 2022. Under the ERSP, Westar Energy and KCP&L's Kansas jurisdiction are required to refund to customers 50% of annual earnings in excess of their authorized return on equity of 9.3% to the extent the excess earnings exceed the amount of Westar Energy's and KCP&L's annual merger bill credits for the year being measured. As of March 31, 2019 , Westar Energy and KCP&L estimate their 2019 annual earnings will not result in a refund obligation. Westar Energy and KCP&L will file their 2019 earnings calculations with the KCC in March 2020. The final refund obligation, if any, will be decided by the KCC and could vary from the current estimate. MPSC Proceedings GMO Other Proceedings In December 2018, the Office of the Public Counsel (OPC) and the Midwest Energy Consumers Group (MECG) filed a petition with the Public Service Commission of the State of Missouri (MPSC) requesting an accounting authority order that would require GMO to record a regulatory liability for all revenues collected from customers for return on investment, non-fuel operations and maintenance costs, taxes including accumulated deferred income taxes, and all other costs associated with Sibley Station following the station’s retirement in November 2018. GMO already records depreciation expense to a regulatory liability for Sibley Station following its retirement pursuant to GMO’s rate order from its 2018 Missouri rate case. GMO opposes OPC’s and MECG’s petition on various grounds, including the value of costs that OPC and MECG allege are no longer existent due to the retirement of Sibley Station and the fact that the retirement of Sibley Station was a long-planned event that was contemplated as part of the stipulations and agreements in GMO’s 2018 Missouri rate case. The MPSC issued an order in March 2019 adopting a procedural schedule to resolve OPC’s and MECG’s petition. A hearing in the case is scheduled for July 2019 with an order expected in the second half of 2019. FERC Proceedings Westar Energy TFR Westar Energy's TFR, effective in January 2019, includes projected 2019 transmission capital expenditures and operating costs and is expected to decrease annual transmission revenues by $11.2 million when compared to 2018. This updated rate provided the basis for Westar Energy's request with the KCC to adjust its retail prices to include updated transmission costs as discussed above. KCP&L TFR KCP&L's TFR, effective in January 2019, includes projected 2019 transmission capital expenditures and operating costs and is expected to decrease annual transmission revenues by $2.8 million when compared to 2018. This updated rate provided the basis for KCP&L's request with the KCC to adjust its retail prices to include updated transmission costs as discussed above.

PENSION PLANS AND POST-RETIREME

PENSION PLANS AND POST-RETIREMENT BENEFITS	3 Months Ended
	Mar. 31, 2019
Retirement Benefits [Abstract]
PENSION PLANS AND POST-RETIREMENT BENEFITS	PENSION PLANS AND POST-RETIREMENT BENEFITS Evergy and certain of its subsidiaries maintain, and Westar Energy and KCP&L participate in, qualified non-contributory defined benefit pension plans covering the majority of Westar Energy's and KCP&L's employees as well as certain non-qualified plans covering certain active and retired officers. Evergy is also responsible for its 94% ownership share of Wolf Creek Generating Station's (Wolf Creek) defined benefit plans, consisting of Westar Energy's and KCP&L's respective 47% ownership shares. For the majority of employees, pension benefits under these plans reflect the employees' compensation, years of service and age at retirement. However, for the plan covering Westar Energy's employees, the benefits for non-union employees hired between 2002 and the second quarter of 2018 and union employees hired beginning in 2012 are derived from a cash balance account formula. The plan was closed to future non-union employees in 2018. For the plans covering KCP&L's employees, the benefits for union employees hired beginning in 2014 are derived from a cash balance account formula and the plans were closed to future non-union employees in 2014. Evergy and its subsidiaries also provide certain post-retirement health care and life insurance benefits for substantially all retired employees of Westar Energy and KCP&L and their respective shares of Wolf Creek's post-retirement benefit plans. The Evergy Companies record pension and post-retirement expense in accordance with rate orders from the KCC and MPSC that allow the difference between pension and post-retirement costs under GAAP and costs for ratemaking to be recognized as a regulatory asset or liability. This difference between financial and regulatory accounting methods is due to timing and will be eliminated over the life of the plans. The following tables provide the components of net periodic benefit costs prior to the effects of capitalization and sharing with joint owners of power plants. Pension Benefits Post-Retirement Benefits Three Months Ended March 31, 2019 Evergy Westar Energy KCP&L Evergy Westar Energy KCP&L Components of net periodic benefit costs (millions) Service cost $ 19.1 $ 7.3 $ 11.8 $ 0.6 $ 0.3 $ 0.3 Interest cost 27.5 13.4 14.1 2.6 1.4 1.2 Expected return on plan assets (27.1 ) (13.7 ) (12.3 ) (2.4 ) (1.7 ) (0.7 ) Prior service cost 0.5 0.4 0.2 0.1 0.1 — Recognized net actuarial (gain)/loss 6.9 6.4 12.2 (0.3 ) (0.1 ) (0.4 ) Net periodic benefit costs before regulatory adjustment and intercompany allocations 26.9 13.8 26.0 0.6 — 0.4 Regulatory adjustment (0.1 ) 0.5 (0.6 ) (0.7 ) (0.8 ) 0.1 Intercompany allocations — — (6.9 ) — — (0.1 ) Net periodic benefit costs $ 26.8 $ 14.3 $ 18.5 $ (0.1 ) $ (0.8 ) $ 0.4 Pension Benefits Post-Retirement Benefits Three Months Ended March 31, 2018 Evergy Westar Energy KCP&L (a) Evergy Westar Energy KCP&L (a) Components of net periodic benefit costs (millions) Service cost $ 8.0 $ 8.0 $ 12.2 $ 0.3 $ 0.3 $ 0.5 Interest cost 12.7 12.7 12.7 1.2 1.2 1.2 Expected return on plan assets (14.0 ) (14.0 ) (13.9 ) (1.7 ) (1.7 ) (0.7 ) Prior service cost 0.2 0.2 0.2 0.1 0.1 — Recognized net actuarial (gain)/loss 8.2 8.2 11.4 (0.1 ) (0.1 ) — Net periodic benefit costs before regulatory adjustment and intercompany allocations 15.1 15.1 22.6 (0.2 ) (0.2 ) 1.0 Regulatory adjustment 2.8 2.8 0.4 (0.4 ) (0.4 ) (0.1 ) Intercompany allocations — — (5.5 ) — — (0.3 ) Net periodic benefit costs $ 17.9 $ 17.9 $ 17.5 $ (0.6 ) $ (0.6 ) $ 0.6 (a) KCP&L amounts are not included in consolidated Evergy for the three months ended March 31, 2018 . The components of net periodic benefit costs other than the service cost component are included in other expense on the Evergy Companies' consolidated statements of income and comprehensive income. See Note 1 for additional details. For the three months ended March 31, 2019 , Evergy, Westar Energy and KCP&L made pension contributions of $12.3 million , $7.1 million and $5.2 million , respectively. Evergy expects to make additional pension contributions of $103.2 million in 2019 to satisfy the Employee Retirement Income Security Act of 1974, as amended (ERISA) funding requirements and KCC and MPSC rate orders, of which $29.9 million is expected to be paid by Westar Energy and $73.3 million is expected to be paid by KCP&L. Also in 2019 , Evergy, Westar Energy and KCP&L expect to make contributions of $2.8 million , $0.7 million and $2.1 million , respectively, to the post-retirement benefit plans.

SHORT-TERM BORROWINGS AND SHORT

SHORT-TERM BORROWINGS AND SHORT-TERM BANK LINES OF CREDIT	3 Months Ended
	Mar. 31, 2019
Debt Disclosure [Abstract]
SHORT-TERM BORROWINGS AND SHORT-TERM BANK LINES OF CREDIT	6 . SHORT-TERM BORROWINGS AND SHORT-TERM BANK LINES OF CREDIT Evergy's $2.5 billion master credit facility expires in 2023 . Evergy, Westar Energy, KCP&L and GMO have borrowing capacity under the master credit facility with specific sublimits for each borrower. These sublimits can be unilaterally adjusted by Evergy for each borrower provided the sublimits remain within minimum and maximum sublimits as specified in the facility. A default by any borrower under the facility or one of their significant subsidiaries on other indebtedness totaling more than $100.0 million constitutes a default under the facility. Under the terms of this facility, each of Evergy, Westar Energy, KCP&L and GMO is required to maintain a total indebtedness to total capitalization ratio, as defined in the facility, of not greater than 0.65 to 1.00 at all times. As of March 31, 2019 , Evergy, Westar Energy, KCP&L and GMO were in compliance with this covenant. The following table summarizes the committed credit facilities (excluding receivable sale facilities discussed in Note 3 and Evergy's term loan credit agreement discussed below) available to the Evergy Companies as of March 31, 2019 and December 31, 2018 . Amounts Drawn Credit Facility Commercial Paper Letters of Credit Cash Borrowings Available Borrowings Weighted Average Interest Rate on Short-Term Borrowings March 31, 2019 (millions) Evergy, Inc. $ 450.0 n/a $ 1.0 $ 100.0 $ 349.0 3.73% Westar Energy 1,000.0 413.8 18.3 — 567.9 2.77% KCP&L 600.0 176.0 2.7 — 421.3 2.89% GMO 450.0 121.2 2.1 — 326.7 2.75% Evergy $ 2,500.0 $ 711.0 $ 24.1 $ 100.0 $ 1,664.9 December 31, 2018 Evergy, Inc. $ 450.0 n/a $ 1.0 $ — $ 449.0 —% Westar Energy 1,000.0 411.7 18.3 — 570.0 3.08% KCP&L 600.0 176.9 2.7 — 420.4 2.95% GMO 450.0 150.0 2.1 — 297.9 3.00% Evergy $ 2,500.0 $ 738.6 $ 24.1 $ — $ 1,737.3 In March 2019, Evergy entered into a $1.0 billion , 6 -month term loan credit agreement with a group of banks to provide short-term financing for its common stock repurchase program. The agreement allows for two term loans during the 6 -month term of the agreement, in an aggregate principal amount not to exceed the credit limit of the agreement. At closing, Evergy borrowed $500.0 million under the agreement, allowing for one additional term loan borrowing in a principal amount up to $500.0 million . At March 31, 2019 , Evergy had $500.0 million of outstanding cash borrowings under the agreement at a weighted-average interest rate of 3.03% . Evergy anticipates repaying borrowings under the term loan credit agreement with proceeds from an expected long-term debt issuance in the second half of 2019.

LONG-TERM DEBT

LONG-TERM DEBT	3 Months Ended
	Mar. 31, 2019
Debt Disclosure [Abstract]
LONG-TERM DEBT	LONG-TERM DEBT Mortgage Bonds In March 2019, KCP&L issued collateral mortgage bonds secured by the General Mortgage Indenture and Deed of Trust dated as of December 1, 1986, as supplemented (KCP&L Mortgage Indenture) to serve as collateral for KCP&L's obligations under the following outstanding unsecured senior notes: • $300.0 million of 3.15% Series, maturing in 2023 ; • $350.0 million of 3.65% Series, maturing in 2025 ; • $250.0 million of 6.05% Series, maturing in 2035 ; • $400.0 million of 5.30% Series, maturing in 2041 ; • $300.0 million of 4.20% Series, maturing in 2047 ; and • $300.0 million of 4.20% Series, maturing in 2048 . The collateral mortgage bonds were issued to the trustee for the unsecured senior notes, are only payable if KCP&L defaults on the underlying unsecured senior notes and do not increase the amount of outstanding debt for KCP&L. As a result of the above transactions, KCP&L's outstanding senior notes have effectively become secured by the mortgage lien of the KCP&L Mortgage Indenture and will rank equally and ratably with all of KCP&L's mortgage bonds, regardless of series, from time to time issued and outstanding under the KCP&L Mortgage Indenture. Also in March 2019, KCP&L issued, at a discount, $400.0 million of 4.125% Mortgage Bonds, maturing in 2049 . KCP&L also repaid its $400.0 million of 7.15% Mortgage Bonds at maturity in April 2019. Senior Notes In March 2019, GMO issued $100.0 million of 3.74% Senior Notes, maturing in 2022 , under a note purchase agreement.

FAIR VALUE MEASUREMENTS

FAIR VALUE MEASUREMENTS	3 Months Ended
	Mar. 31, 2019
Fair Value Disclosures [Abstract]
FAIR VALUE MEASUREMENTS	FAIR VALUE MEASUREMENTS Values of Financial Instruments GAAP establishes a hierarchical framework for disclosing the transparency of the inputs utilized in measuring assets and liabilities at fair value. Management's assessment of the significance of a particular input to the fair value measurement requires judgment and may affect the classification of assets and liabilities within the fair value hierarchy levels. In addition, the Evergy Companies measure certain investments that do not have a readily determinable fair value at net asset value (NAV), which are not included in the fair value hierarchy. Further explanation of these levels and NAV is summarized below. Level 1 – Quoted prices are available in active markets for identical assets or liabilities. The types of assets and liabilities included in Level 1 are highly liquid and actively traded instruments with quoted prices, such as equities listed on public exchanges. Level 2 – Pricing inputs are not quoted prices in active markets, but are either directly or indirectly observable. The types of assets and liabilities included in Level 2 are certain marketable debt securities, financial instruments traded in less than active markets or other financial instruments priced with models using highly observable inputs. Level 3 – Significant inputs to pricing have little or no transparency. The types of assets and liabilities included in Level 3 are those with inputs requiring significant management judgment or estimation. NAV - Investments that do not have a readily determinable fair value are measured at NAV. These investments do not consider the observability of inputs and, therefore, they are not included within the fair value hierarchy. The Evergy Companies include in this category investments in private equity, real estate and alternative investment funds that do not have a readily determinable fair value. The underlying alternative investments include collateralized debt obligations, mezzanine debt and a variety of other investments. The Evergy Companies record cash and cash equivalents, accounts receivable and short-term borrowings on their consolidated balance sheets at cost, which approximates fair value due to the short-term nature of these instruments. Interest Rate Derivatives The Evergy Companies are exposed to market risks arising from changes in interest rates and may use derivative instruments to manage these risks. From time to time, this may include entering into interest rate swap agreements to protect against unfavorable interest rate changes relating to forecasted debt transactions. These interest rate swap agreements can be designated as cash flow hedges, in which case gains and losses on the interest rate swaps are deferred in other comprehensive income to be recognized as an adjustment to interest expense over the same period that the hedged interest payments affect earnings. In December 2018, Evergy entered into an interest rate swap agreement with a notional amount of $500.0 million that has been designated as a cash flow hedge of interest payments from a forecasted debt issuance in 2019. As of March 31, 2019 and December 31, 2018, the interest rate swap had a fair value of $(19.2) million and $(5.4) million , respectively, and was recorded within other current liabilities on Evergy's consolidated balance sheet. For the three months ended March 31, 2019 , Evergy recorded a $13.8 million pre-tax loss in other comprehensive loss on Evergy's consolidated statements of comprehensive income. Fair Value of Long-Term Debt The Evergy Companies measure the fair value of long-term debt using Level 2 measurements available as of the measurement date. The book value and fair value of the Evergy Companies' long-term debt and long-term debt of variable interest entities is summarized in the following table. March 31, 2019 December 31, 2018 Book Value Fair Value Book Value Fair Value Long-term debt (a) (millions) Evergy (b) $ 7,827.0 $ 8,130.5 $ 7,341.7 $ 7,412.1 Westar Energy 3,690.0 3,884.4 3,689.8 3,771.3 KCP&L 2,924.6 3,130.2 2,530.1 2,637.5 Long-term debt of variable interest entities (a) Evergy $ 51.1 $ 50.9 $ 81.4 $ 81.3 Westar Energy 51.1 50.9 81.4 81.3 (a) Includes current maturities. (b) Book value as of March 31, 2019 and December 31, 2018 , includes $136.8 million and $144.8 million , respectively, of fair value adjustments recorded in connection with purchase accounting for the Great Plains Energy and Westar Energy merger, which are not part of future principal payments and will amortize over the remaining life of the associated debt instrument. Recurring Fair Value Measurements The following tables include the Evergy Companies' balances of financial assets and liabilities measured at fair value on a recurring basis. Description March 31, 2019 Level 1 Level 2 Level 3 NAV Westar Energy (millions) Assets Nuclear decommissioning trust (a) Domestic equity funds $ 80.1 $ 73.6 $ — $ — $ 6.5 International equity funds 46.5 46.5 — — — Core bond fund 34.6 34.6 — — — High-yield bond fund 20.6 20.6 — — — Emerging markets bond fund 16.4 16.4 — — — Combination debt/equity/other fund 14.7 14.7 — — — Alternative investments fund 23.3 — — — 23.3 Real estate securities fund 12.0 — — — 12.0 Cash equivalents 0.2 0.2 — — — Total nuclear decommissioning trust 248.4 206.6 — — 41.8 Rabbi trust Core bond fund 24.7 — — — 24.7 Combination debt/equity/other fund 6.2 — — — 6.2 Cash equivalents 0.2 0.2 — — — Total rabbi trust 31.1 0.2 — — 30.9 Total $ 279.5 $ 206.8 $ — $ — $ 72.7 KCP&L Assets Nuclear decommissioning trust (a) Equity securities $ 188.3 $ 188.3 $ — $ — $ — Debt securities U.S. Treasury 46.0 46.0 — — — U.S. Agency 0.4 — 0.4 — — State and local obligations 2.1 — 2.1 — — Corporate bonds 30.6 — 30.6 — — Foreign governments 0.1 — 0.1 — — Cash equivalents 2.9 2.9 — — — Other (0.5 ) — (0.5 ) — — Total nuclear decommissioning trust 269.9 237.2 32.7 — — Self-insured health plan trust (b) Equity securities 0.5 0.5 — — — Debt securities 4.3 0.4 3.9 — — Cash and cash equivalents 6.7 6.7 — — — Other 1.1 — 1.1 — — Total self-insured health plan trust 12.6 7.6 5.0 — — Total $ 282.5 $ 244.8 $ 37.7 $ — $ — Other Evergy Assets Rabbi trusts Fixed income fund $ 13.1 $ — $ — $ — $ 13.1 Cash and cash equivalents 0.4 0.4 — — — Total rabbi trusts $ 13.5 $ 0.4 $ — $ — $ 13.1 Liabilities Interest rate swaps (c) $ 19.2 $ — $ 19.2 $ — $ — Total $ 19.2 $ — $ 19.2 $ — $ — Evergy Assets Nuclear decommissioning trust (a) $ 518.3 $ 443.8 $ 32.7 $ — $ 41.8 Rabbi trusts 44.6 0.6 — — 44.0 Self-insured health plan trust (b) 12.6 7.6 5.0 — — Total $ 575.5 $ 452.0 $ 37.7 $ — $ 85.8 Liabilities Interest rate swaps (c) $ 19.2 $ — $ 19.2 $ — $ — Total $ 19.2 $ — $ 19.2 $ — $ — Description December 31, 2018 Level 1 Level 2 Level 3 NAV Westar Energy (millions) Assets Nuclear decommissioning trust (a) Domestic equity funds $ 70.6 $ 63.9 $ — $ — $ 6.7 International equity funds 36.2 36.2 — — — Core bond fund 37.5 37.5 — — — High-yield bond fund 18.9 18.9 — — — Emerging markets bond fund 15.4 15.4 — — — Combination debt/equity/other fund 12.9 12.9 — — — Alternative investments fund 24.1 — — — 24.1 Real estate securities fund 11.8 — — — 11.8 Cash equivalents 0.1 0.1 — — — Total nuclear decommissioning trust 227.5 184.9 — — 42.6 Rabbi trust Core bond fund 24.8 — — — 24.8 Combination debt/equity/other fund 5.6 — — — 5.6 Cash equivalents 0.2 0.2 — — — Total rabbi trust 30.6 0.2 — — 30.4 Total $ 258.1 $ 185.1 $ — $ — $ 73.0 KCP&L Assets Nuclear decommissioning trust (a) Equity securities $ 166.6 $ 166.6 $ — $ — $ — Debt securities U.S. Treasury 42.1 42.1 — — — U.S. Agency 0.4 — 0.4 — — State and local obligations 2.1 — 2.1 — — Corporate bonds 30.9 — 30.9 — — Foreign governments 0.1 — 0.1 — — Cash equivalents 1.7 1.7 — — — Other 0.7 0.7 — — — Total nuclear decommissioning trust 244.6 211.1 33.5 — — Self-insured health plan trust (b) Equity securities 0.5 0.5 — — — Debt securities 3.9 0.3 3.6 — — Cash and cash equivalents 8.0 8.0 — — — Total self-insured health plan trust 12.4 8.8 3.6 — — Total $ 257.0 $ 219.9 $ 37.1 $ — $ — Other Evergy Assets Rabbi trusts Fixed income fund $ 13.2 $ — $ — $ — $ 13.2 Total rabbi trusts $ 13.2 $ — $ — $ — $ 13.2 Liabilities Interest rate swaps (c) $ 5.4 $ — $ 5.4 $ — $ — Total $ 5.4 $ — $ 5.4 $ — $ — Evergy Assets Nuclear decommissioning trust (a) $ 472.1 $ 396.0 $ 33.5 $ — $ 42.6 Rabbi trust 43.8 0.2 — — 43.6 Self-insured health plan trust (b) 12.4 8.8 3.6 — — Total $ 528.3 $ 405.0 $ 37.1 $ — $ 86.2 Liabilities Interest rate swaps (c) $ 5.4 $ — $ 5.4 $ — $ — Total $ 5.4 $ — $ 5.4 $ — $ — (a) Fair value is based on quoted market prices of the investments held by the trust and/or valuation models. (b) Fair value is based on quoted market prices of the investments held by the trust. Debt securities classified as Level 1 are comprised of U.S. Treasury securities. Debt securities classified as Level 2 are comprised of corporate bonds, U.S. Agency, state and local obligations, and other asset-backed securities. (c) The fair value of interest rate swaps are determined by calculating the net present value of expected payments and receipts under the interest rate swaps using observable market inputs including interest rates and LIBOR swap rates. Certain Evergy and Westar Energy investments included in the table above are measured at NAV as they do not have readily determinable fair values. In certain situations, these investments may have redemption restrictions. The following table provides additional information on these Evergy and Westar Energy investments. March 31, 2019 December 31, 2018 March 31, 2019 Fair Unfunded Fair Unfunded Redemption Length of Value Commitments Value Commitments Frequency Settlement Westar Energy (millions) Nuclear decommissioning trust: Domestic equity funds $ 6.5 $ 4.0 $ 6.7 $ 4.3 (a) (a) Alternative investments fund (b) 23.3 — 24.1 — Quarterly 65 days Real estate securities fund (b) 12.0 — 11.8 — Quarterly 65 days Total $ 41.8 $ 4.0 $ 42.6 $ 4.3 Rabbi trust: Core bond fund $ 24.7 $ — $ 24.8 $ — (c) (c) Combination debt/equity/other fund 6.2 — 5.6 — (c) (c) Total $ 30.9 $ — $ 30.4 $ — Other Evergy Rabbi trusts: Fixed income fund $ 13.1 $ — $ 13.2 $ — (c) (c) Total Evergy investments at NAV $ 85.8 $ 4.0 $ 86.2 $ 4.3 (a) This investment is in five long-term private equity funds that do not permit early withdrawal. Investments in these funds cannot be distributed until the underlying investments have been liquidated, which may take years from the date of initial liquidation. Three funds have begun to make distributions. The initial investment in the fourth and fifth fund occurred in the second quarter of 2016 and first quarter of 2018, respectively. The fourth fund's term is 15 years , subject to the general partner's right to extend the term for up to three additional one -year periods. The fifth fund's term will be 15 years after the initial closing date, subject to additional extensions approved by the Advisory Committee to provide for an orderly liquidation of fund investments and dissolution of the fund. (b) There is a holdback on final redemptions. (c) This investment can be redeemed immediately and is not subject to any restrictions on redemptions. The Evergy Companies hold equity and debt investments classified as securities in various trusts including for the purposes of funding the decommissioning of Wolf Creek and for the benefit of certain retired executive officers of Westar Energy. The Evergy Companies record net realized and unrealized gains and losses on the nuclear decommissioning trusts in regulatory liabilities on their consolidated balance sheets and record net realized and unrealized gains and losses on Westar Energy's rabbi trust in the consolidated statements of income and comprehensive income. The following table summarizes the net unrealized gains (losses) for the Evergy Companies' nuclear decommissioning trusts and rabbi trusts. Three Months Ended March 31 2019 2018 Westar Energy (millions) Nuclear decommissioning trust - equity securities $ 17.2 $ (11.7 ) Rabbi trust 1.3 (0.5 ) Total $ 18.5 $ (12.2 ) KCP&L (a) Nuclear decommissioning trust - equity securities $ 20.7 $ (3.6 ) Nuclear decommissioning trust - debt securities 2.1 (1.6 ) Total $ 22.8 $ (5.2 ) Evergy Nuclear decommissioning trust - equity securities $ 37.9 $ (11.7 ) Nuclear decommissioning trust - debt securities 2.1 — Rabbi trusts 0.5 (0.5 ) Total $ 40.5 $ (12.2 ) (a) KCP&L amounts are not included in consolidated Evergy for the three months ended March 31, 2018 .

COMMITMENTS AND CONTINGENCIES

COMMITMENTS AND CONTINGENCIES	3 Months Ended
	Mar. 31, 2019
Commitments and Contingencies Disclosure [Abstract]
COMMITMENTS AND CONTINGENCIES	COMMITMENTS AND CONTINGENCIES Environmental Matters Set forth below are descriptions of contingencies related to environmental matters that may impact the Evergy Companies' operations or their financial results. Management's assessment of these contingencies, which are based on federal and state statutes and regulations, and regulatory agency and judicial interpretations and actions, has evolved over time. There are a variety of final and proposed laws and regulations that could have a material adverse effect on the Evergy Companies' operations and consolidated financial results. Due in part to the complex nature of environmental laws and regulations, the Evergy Companies are unable to assess the impact of potential changes that may develop with respect to the environmental contingencies described below. Cross-State Air Pollution Update Rule In September 2016, the Environmental Protection Agency (EPA) finalized the Cross-State Air Pollution Update Rule (CSAPR). The final rule addresses interstate transport of nitrogen oxides emissions in 22 states including Kansas, Missouri and Oklahoma during the ozone season and the impact from the formation of ozone on downwind states with respect to the 2008 ozone National Ambient Air Quality Standards (NAAQS). Starting with the 2017 ozone season, the final rule revised the existing ozone season allowance budgets for Missouri and Oklahoma and established an ozone season budget for Kansas. In December 2018, the EPA finalized the CSAPR Close-Out Rule, which determined that the existing CSAPR Update Rule fully addresses applicable states' interstate pollution transport obligations for the 2008 ozone NAAQS. Therefore, the EPA is proposing no additional reduction in the current ozone season allowance budgets in order to address obligations for the 2008 ozone NAAQS. Various states and others are challenging the rule in the U.S. Court of Appeals for the D.C. Circuit (D.C. Circuit), but the rule remains in effect. It is not expected that this rule will have a material impact on the Evergy Companies' operations and consolidated financial results. National Ambient Air Quality Standards Under the Clean Air Act Amendments of 1990 (CAA), the EPA set NAAQS for certain emissions known as the "criteria pollutants" considered harmful to public health and the environment, including two classes of particulate matter (PM), ozone, nitrogen dioxide (NO 2 ) (a precursor to ozone), carbon monoxide and sulfur dioxide (SO 2 ), which result from fossil fuel combustion. Areas meeting the NAAQS are designated attainment areas while those that do not meet the NAAQS are considered nonattainment areas. Each state must develop a plan to bring nonattainment areas into compliance with the NAAQS. NAAQS must be reviewed by the EPA at five -year intervals. In October 2015, the EPA strengthened the ozone NAAQS by lowering the standards from 75 ppb to 70 ppb. In November 2017, the EPA designated all counties in the State of Kansas as well as the Missouri counties in KCP&L's and GMO's service territories as attainment/unclassifiable. It is not expected that this will have a material impact on the Evergy Companies' consolidated financial results. If areas surrounding the Evergy Companies' facilities are designated in the future as nonattainment and/or it is required to install additional equipment to control emissions at facilities of the Evergy Companies, it could have a material impact on the operations and consolidated financial results of the Evergy Companies. Greenhouse Gases Burning coal and other fossil fuels releases carbon dioxide (CO 2 ) and other gases referred to as greenhouse gases (GHG). Various regulations under the federal CAA limit CO 2 and other GHG emissions, and in addition, other measures are being imposed or offered by individual states, municipalities and regional agreements with the goal of reducing GHG emissions. In October 2015, the EPA published a rule establishing new source performance standards (NSPS) for GHGs that limit CO 2 emissions for new, modified and reconstructed coal and natural gas fueled electric generating units to various levels per MWh depending on various characteristics of the units. Legal challenges to the GHG NSPS have been filed in the D.C. Circuit by various states and industry members. Also in October 2015, the EPA published a rule establishing guidelines for states to regulate CO 2 emissions from existing power plants. The standards for existing plants are known as the Clean Power Plan (CPP). Under the CPP, interim emissions performance rates must be achieved beginning in 2022 and final emissions performance rates must be achieved by 2030. Legal challenges to the CPP were filed by groups of states and industry members, including Westar Energy, in the D.C. Circuit. The CPP was stayed by the Supreme Court in February 2016 and, accordingly, is not currently being implemented by the states. In April 2017, the EPA published in the Federal Register a notice of withdrawal of the proposed CPP federal plan, proposed model trading rules and proposed Clean Energy Incentive Program design details. Also in April 2017, the EPA published a notice in the Federal Register that it was initiating administrative reviews of the CPP and the GHG NSPS. In October 2017, the EPA issued a proposed rule to repeal the CPP. The proposed rule indicates the CPP exceeds the EPA’s authority and the EPA has not determined whether they will issue a replacement rule. The EPA solicited comments on the legal interpretations contained in this rulemaking. In December 2017, the EPA issued an advance notice of proposed rulemaking to solicit feedback on specific areas of the CPP that could be changed. In August 2018, the EPA published in the Federal Register proposed regulations, which contained (1) emission guidelines for GHG emissions from existing electric utility generating units (EGUs), (2) revisions to emission guideline implementing regulations and (3) revisions to the new source review (NSR) program. The proposed emission guidelines are better known as the Affordable Clean Energy (ACE) Rule. The ACE Rule would establish emission guidelines for states to use in the development of plans to reduce GHG emissions from existing coal-fired EGUs. The ACE Rule is also the replacement rule for the CPP. The ACE rule proposes to determine the "best system of emission reduction" (BSER) for GHG emissions from existing coal-fired EGUs as on-site, heat-rate efficiency improvements. The proposed rule also provides states with a list of candidate technologies that can be used to establish standards of performance and incorporate these performance standards into state plans. In order for the states to be able to effectively implement the proposed emission guidelines contained in the ACE Rule, the EPA is proposing new regulations under 111(d) of the CAA to help clarify this process. In addition, the EPA is proposing revisions to the NSR program that will reduce the likelihood of triggering NSR for proposed heat-rate efficiency improvement projects at existing coal-fired EGUs. The public comment period for these proposed regulatory changes closed on October 31, 2018. In December 2018, the EPA released a proposed rule to revise the existing GHG NSPS for new, modified and reconstructed fossil fuel-fired EGUs, which was issued in October 2015. This proposed rule would determine that BSER for new EGUs is "the most efficient demonstrated steam cycle (e.g. supercritical steam conditions for large units and subcritical steam conditions for small units) in combination with the best operating practices." This replaces the current determination that BSER for these units is the use of partial carbon capture and sequestration technology. The EPA is also proposing to address, in potential future rule making, existing operational limitations imposed by the rule on aero-derivative simple cycle combustion turbines. Due to the future uncertainty of the CPP and ACE Rule, the Evergy Companies cannot determine the impact on their operations or consolidated financial results, but the cost to comply with the CPP, should it be upheld and implemented in its current or a substantially similar form, or ACE in its current or a substantially similar form, could be material. Water The Evergy Companies discharge some of the water used in generation and other operations. This water may contain substances deemed to be pollutants. A November 2015 EPA rule establishes effluent limitations guidelines (ELG) and standards for wastewater discharges, including limits on the amount of toxic metals and other pollutants that can be discharged. Implementation timelines for these requirements vary from 2018 to 2023. In April 2017, the EPA announced it is reconsidering the ELG rule. In September 2017, the EPA finalized a rule to postpone the compliance dates for the new, more stringent, effluent limitations and pretreatment standards for bottom ash transport water and flue gas desulfurization wastewater. These compliance dates have been postponed for two years while the EPA completes its administrative reconsideration of the ELG rule. In April 2019, the U.S. Court of Appeals for the 5th Circuit (5th Circuit) issued a ruling that vacates and remands portions of the ELG rule. The 5th Circuit ruled in favor of environmental groups who argued that EPA did not set appropriate limits for the best available technology economically achievable for legacy waste water and leachate. The Evergy Companies are evaluating the 5th Circuit ruling, the existing ELG rule and related developments and cannot predict the resulting impact on their operations or consolidated financial results, but believe costs to comply could be material if the rule is implemented in its current or substantially similar form. In October 2014, the EPA's final standards for cooling intake structures at power plants to protect aquatic life took effect. The standards, based on Section 316(b) of the federal Clean Water Act (CWA), require subject facilities to choose among seven best available technology options to reduce fish impingement. In addition, some facilities must conduct studies to assist permitting authorities to determine whether and what site-specific controls, if any, would be required to reduce entrainment of aquatic organisms. The Evergy Companies' current analysis indicates this rule will not have a significant impact on their coal plants that employ cooling towers or cooling lakes that can be classified as closed cycle cooling and do not expect the impact from this rule to be material. Plants without closed cycle cooling are under evaluation for compliance with these standards and may require additional controls that could be material. KCP&L holds a permit from the Missouri Department of Natural Resources (MDNR) covering water discharge from its Hawthorn Station. The permit authorizes KCP&L to, among other things, withdraw water from the Missouri River for cooling purposes and return the heated water to the Missouri River. KCP&L has applied for a renewal of this permit and the EPA has submitted an interim objection letter regarding the allowable amount of heat that can be contained in the returned water. Until this matter is resolved, KCP&L continues to operate under its current permit. Evergy and KCP&L cannot predict the outcome of this matter; however, while less significant outcomes are possible, this matter may require a reduction in generation, installation of cooling towers or other technology to cool the water, or both, any of which could have a material impact on Evergy's and KCP&L's operations and consolidated financial results. In June 2015, the EPA along with the U.S. Army Corps of Engineers issued a final rule, effective August 2015, defining the Waters of the United States (WOTUS) for purposes of the CWA. This rulemaking has the potential to impact all programs under the CWA. Expansion of regulated waterways is possible under the rule depending on regulating authority interpretation, which could impact several permitting programs. Various states and others have filed lawsuits challenging the WOTUS rule. In February 2018, the EPA and the U.S. Army Corps of Engineers finalized a rule adding an applicability date to the 2015 rule, which makes the implementation date of the rule February 2020. In December 2018, the EPA and the U.S. Army Corps of Engineers published in the Federal Register a proposed rule titled "Revised Definition of Waters of the United States." This proposed rule narrows the extent of the CWA jurisdiction as compared to the 2015 rule. The Evergy Companies are currently evaluating the WOTUS rule and related developments, but do not believe the rule, if upheld and implemented in its current or substantially similar form, will have a material impact on the Evergy Companies' operations or consolidated financial results. Regulation of Coal Combustion Residuals In the course of operating their coal generation plants, the Evergy Companies produce coal combustion residuals (CCRs), including fly ash, gypsum and bottom ash. Some of this ash production is recycled, principally by selling to the aggregate industry. The EPA published a rule to regulate CCRs in April 2015, which will require additional CCR handling, processing and storage equipment and closure of certain ash disposal units. The Water Infrastructure Improvements for the Nation (WIIN) Act allows states to achieve delegated authority for CCR rules from the EPA. This has the potential to impact compliance options. In July 2018, the Kansas Department of Health and Environment (KDHE) submitted a CCR permit program application to the EPA under authority of the WIIN Act. In November 2018, KDHE received notice from the EPA that its application is deficient and requested additional clarifying information. KDHE has decided it is not going to move forward with additional submittals at this time and will wait until current legal action associated with the CCR rule is final along with planned upcoming modifications to the CCR rule. In February 2019, MDNR issued a proposed CCR rule. The public comment period for this proposed rule closed in March 2019. Once a final state rule is promulgated, then MDNR will submit a WIIN Act application to the EPA to gain authority over the federal CCR program. Similar to the process in Kansas, this would allow Missouri state regulators to gain control of the CCR program. It will take up to one year from submittal of the Missouri application for the EPA to take final action and grant authority to the state, if such authority is granted. EPA submitted comments during the recent public comment period which included concerns around this proposed rule not being as protective as the federal CCR rule. On July 30, 2018, the EPA published in the Federal Register a final rule called the Phase I, Part I CCR Remand Rule to modify portions of the 2015 rulemaking. The Phase I, Part I rule provides a timeline extension for unlined impoundments and landfills that must close due to groundwater impacts or location restrictions. The rule also sets risk-based limits for certain groundwater constituents where a maximum contaminant level did not previously exist. These rule modifications add flexibility when assessing compliance. On August 21, 2018, the D.C. Circuit issued a ruling in the CCR rule litigation between the Utility Solid Waste Activities Group, the EPA and environmental organizations. Portions of the rule were vacated and were remanded back to the EPA for potential modification. Potential revisions to remanded sections will force all unlined surface impoundments to close regardless of groundwater conditions. Any changes to the rule based on this court decision will require additional rulemaking from the EPA. In October 2018, a coalition of environmental groups (including Sierra Club) filed a petition for review in the D.C. Circuit challenging the Phase I, Part I revisions to the CCR Rule. In November 2018, this coalition requested the EPA to stay the October 31, 2020 deadline extension for initiating closure for unlined impoundments and landfills that must close due to groundwater impacts or location restrictions. The EPA has rejected this request and the coalition has filed a petition with the D.C. Circuit for a similar stay. In response, the EPA filed a motion with the D.C. Circuit to voluntarily remand without vacatur the Part I, Phase I rule. In March 2019, the D.C. Circuit issued a ruling to grant EPA's motion to remand the rule without vacatur. This ruling maintains the current October 31, 2020 deadline extension. As EPA works on a rule modification, it is possible that this October 31, 2020 deadline will be modified. If the date is moved up then some CCR units in the Evergy Companies' fleet could have to initiate closure on an earlier timeline than currently planned, the results of which could be material. The Evergy Companies have recorded asset retirement obligations (AROs) for their current estimates for the closure of ash disposal ponds, but the revision of these AROs may be required in the future due to changes in existing CCR regulations, the results of groundwater monitoring of CCR units or changes in interpretation of existing CCR regulations or changes in the timing or cost to close ash disposal ponds. If revisions to these AROs are necessary, the impact on the Evergy Companies' operations or consolidated financial results could be material.

RELATED PARTY TRANSACTIONS AND

RELATED PARTY TRANSACTIONS AND RELATIONSHIPS	3 Months Ended
	Mar. 31, 2019
Related Party Transactions [Abstract]
RELATED PARTY TRANSACTIONS AND RELATIONSHIPS	10 . RELATED PARTY TRANSACTIONS AND RELATIONSHIPS In the normal course of business, Westar Energy, KCP&L and GMO engage in related party transactions with one another. A summary of these transactions and the amounts associated with them is provided below. Transactions between Westar Energy and either KCP&L or GMO for the three months ended March 31, 2018 are not reflected below as they occurred prior to the merger. Jointly-Owned Plants and Shared Services KCP&L employees manage GMO's business and operate its facilities at cost, including GMO's 18% ownership interest in KCP&L's Iatan Nos. 1 and 2. The operating expenses and capital costs billed from KCP&L to GMO were $42.0 million and $46.4 million for the three months ended March 31, 2019 and 2018, respectively. Westar Energy employees manage Jeffrey Energy Center and operate its facilities at cost, including GMO's 8% ownership interest in Jeffrey Energy Center. The operating expenses and capital costs billed from Westar Energy to GMO for Jeffrey Energy Center and other various business activities were $6.3 million for the three months ended March 31, 2019 . KCP&L employees manage La Cygne Station and operate its facilities at cost, including Westar Energy's 50% ownership interest in La Cygne Station. KCP&L and Westar Energy employees also provide one another with shared service support, including costs related to human resources, information technology, accounting and legal services. The operating expenses and capital costs billed from KCP&L to Westar Energy were $31.5 million for the three months ended March 31, 2019 . The operating and capital costs billed from Westar Energy to KCP&L were $7.4 million for the three months ended March 31, 2019 . Money Pool KCP&L and GMO are also authorized to participate in the Evergy, Inc. money pool, an internal financing arrangement in which funds may be lent on a short-term basis to KCP&L and GMO from Evergy, Inc. and between KCP&L and GMO. At March 31, 2019 and December 31, 2018 , KCP&L had no outstanding receivables or payables under the money pool. Related Party Net Receivables and Payables The following table summarizes Westar Energy's and KCP&L's related party net receivables and payables. March 31 December 31 2019 2018 Westar Energy (millions) Net receivable from GMO $ 2.5 $ 2.6 Net payable to KCP&L (8.3 ) (13.5 ) Net payable to Evergy (0.5 ) (1.4 ) KCP&L Net receivable from GMO $ 53.6 $ 72.6 Net receivable from Westar Energy 8.3 13.5 Net receivable from Evergy 19.3 15.7 Tax Allocation Agreement Evergy files a consolidated federal income tax return as well as unitary and combined income tax returns in several state jurisdictions with Kansas and Missouri being the most significant. Income taxes for consolidated or combined subsidiaries are allocated to the subsidiaries based on separate company computations of income or loss. As of March 31, 2019 and December 31, 2018 , Westar Energy had income taxes receivable from Evergy of $32.0 million and $42.7 million , respectively. As of March 31, 2019 and December 31, 2018 , KCP&L had income taxes payable to Evergy of $10.6 million and $2.0 million , respectively. Leases KCP&L leases certain transmission equipment from Westar Energy. This lease was entered into prior to the merger in an arms-length transaction and is accounted for as an operating lease. As of March 31, 2019 , KCP&L had a right-of-use asset of $30.0 million recorded within other long-term assets, $0.6 million of lease liability recorded in other current liabilities and $29.4 million of lease liability recorded in other long-term liabilities on its consolidated balance sheet related to this lease.

SHAREHOLDERS' EQUITY

SHAREHOLDERS' EQUITY	3 Months Ended
	Mar. 31, 2019
Stockholders' Equity Note [Abstract]
SHAREHOLDERS' EQUITY	SHAREHOLDERS' EQUITY Common Stock Repurchase Program In July 2018, the Evergy Board authorized the repurchase of up to 60 million shares of Evergy's common stock. Although this repurchase authorization has no expiration date, Evergy expects to repurchase approximately 60 million shares by mid-2020. Evergy plans to utilize various methods to effectuate the share repurchase program, including but not limited to, a series of transactions that may include accelerated share repurchases (ASRs), open market transactions or other means, subject to market conditions and applicable legal requirements. The repurchase program may be suspended, discontinued or resumed at any time. For the three months ended March 31, 2019 , Evergy had total repurchases of common stock of $578.3 million and had repurchased 10.5 million shares under the repurchase program. Since its inception, Evergy has made total repurchases of common stock of approximately $1.6 billion and has repurchased 26.9 million shares under the repurchase program. These repurchase totals include shares repurchased under an ASR agreement that had not reached final settlement as of March 31, 2019, and is discussed further below. In November 2018, Evergy entered into an ASR agreement with a financial institution to purchase $475.0 million of Evergy common stock. In December 2018, the financial institution delivered to Evergy 6.4 million shares of common stock, representing a partial settlement of the contract, based on then-current market prices and Evergy paid a total of $475.0 million . The ASR agreement reached final settlement in February 2019 and resulted in the delivery of an additional 1.9 million shares to Evergy based on the average daily volume weighted-average price of Evergy common stock during the term of the ASR agreement, less a negotiated discount. In March 2019, Evergy entered into an ASR agreement with a financial institution to purchase $450.0 million of Evergy common stock. In March 2019, the financial institution delivered to Evergy 6.3 million shares of common stock, representing a partial settlement of the contract, based on then-current market prices and Evergy paid a total of $450.0 million . The final number of shares of Evergy common stock that Evergy may receive or be required to remit upon settlement of the ASR agreement will be based on the average daily volume weighted-average price of Evergy common stock during the term of the ASR agreement, less a negotiated discount. Final settlement of the ASR agreement will occur by June 2019, but may occur earlier at the option of the financial institution. Evergy expects that the final settlement of the ASR agreement will result in the delivery of additional shares of common stock to Evergy at no additional cost. Evergy reflects ASRs as a repurchase of common stock in the period the shares are delivered for purposes of calculating earnings per share and as forward contracts indexed to its own common stock. Evergy's ASRs have met all of the applicable criteria for equity classification and therefore are not accounted for as derivative instruments. Dividend Restrictions Evergy depends on its subsidiaries to pay dividends on its common stock. The Evergy Companies have certain restrictions stemming from statutory requirements, corporate organizational documents, covenants and other conditions that could affect dividend levels or the ability to pay dividends. The KCC order authorizing the merger transaction requires Evergy to maintain consolidated common equity of at least 35% of total consolidated capitalization. Under the Federal Power Act, Westar Energy, KCP&L and GMO generally can pay dividends only out of retained earnings. Certain conditions in the MPSC and KCC orders authorizing the merger transaction also require Westar Energy and KCP&L to maintain consolidated common equity of at least 40% of total capitalization. Other conditions in the MPSC and KCC merger orders require Westar Energy, KCP&L and GMO to maintain credit ratings of at least investment grade. If Westar Energy's, KCP&L's or GMO's credit ratings are downgraded below the investment grade level as a result of their affiliation with Evergy or any of Evergy's affiliates, the impacted utility shall not pay a dividend to Evergy without KCC or MPSC approval or until the impacted utility's investment grade credit rating has been restored. The master credit facility of Evergy, Westar Energy, KCP&L and GMO, the term loan agreement of Evergy and the note purchase agreements for certain GMO senior notes contain covenants requiring the respective company to maintain a consolidated indebtedness to consolidated total capitalization ratio of not more than 0.65 to 1.00 at all times. As of March 31, 2019 , all of Evergy's and Westar Energy's retained earnings and net income were free of restrictions and KCP&L had a retained earnings restriction of $471.2 million . Evergy's subsidiaries had restricted net assets of approximately $5.4 billion as of March 31, 2019 . These restrictions are not expected to affect the Evergy Companies' ability to pay dividends at the current level for the foreseeable future.

TAXES

TAXES	3 Months Ended
	Mar. 31, 2019
Income Tax Disclosure [Abstract]
TAXES	TAXES Components of income tax expense are detailed in the following tables. Evergy Three Months Ended March 31 2019 2018 Current income taxes (millions) Federal $ 11.9 $ 0.2 State (0.6 ) — Total 11.3 0.2 Deferred income taxes Federal (7.3 ) 5.9 State 6.3 3.7 Total (1.0 ) 9.6 Investment tax credit amortization (1.0 ) (0.6 ) Income tax expense $ 9.3 $ 9.2 Westar Energy Three Months Ended March 31 2019 2018 Current income taxes (millions) Federal $ 10.4 $ 0.2 State 0.4 — Total 10.8 0.2 Deferred income taxes Federal (3.2 ) 5.9 State 3.6 3.7 Total 0.4 9.6 Investment tax credit amortization (0.7 ) (0.6 ) Income tax expense $ 10.5 $ 9.2 KCP&L (a) Three Months Ended March 31 2019 2018 Current income taxes (millions) Federal $ 7.9 $ (1.3 ) State 0.8 (0.5 ) Total 8.7 (1.8 ) Deferred income taxes Federal (5.2 ) 3.6 State 0.4 2.0 Total (4.8 ) 5.6 Investment tax credit amortization (0.2 ) (0.3 ) Income tax expense $ 3.7 $ 3.5 (a) KCP&L amounts are not included in consolidated Evergy for the three months ended March 31, 2018. Effective Income Tax Rates Effective income tax rates reflected in the financial statements and the reasons for their differences from the statutory federal rates are detailed in the following tables. Evergy Three Months Ended March 31 2019 2018 Federal statutory income tax rate 21.0 % 21.0 % Effect of: COLI policies (1.8 ) (3.1 ) State income taxes 4.6 4.2 Flow through depreciation for plant-related differences (4.4 ) 0.9 Federal tax credits (3.9 ) (9.5 ) Non-controlling interest (0.3 ) (0.5 ) AFUDC equity — (0.2 ) Amortization of federal investment tax credits (0.5 ) (0.6 ) Valuation allowance (7.0 ) 2.1 Stock compensation 0.1 (1.1 ) Officer compensation limitation 0.2 — Other 0.2 (0.5 ) Effective income tax rate 8.2 % 12.7 % Westar Energy Three Months Ended March 31 2019 2018 Federal statutory income tax rate 21.0 % 21.0 % Effect of: COLI policies (3.2 ) (3.1 ) State income taxes 5.0 4.2 Flow through depreciation for plant-related differences (0.1 ) 0.9 Federal tax credits (6.1 ) (9.5 ) Non-controlling interest (0.6 ) (0.5 ) AFUDC equity (0.1 ) (0.2 ) Amortization of federal investment tax credits (0.7 ) (0.6 ) Valuation allowance (2.1 ) 2.1 Stock compensation (0.1 ) (1.1 ) Other 0.3 (0.5 ) Effective income tax rate 13.3 % 12.7 % KCP&L Three Months Ended March 31 2019 2018 Federal statutory income tax rate 21.0 % 21.0 % Effect of: COLI policies (0.1 ) — State income taxes 4.9 5.1 Flow through depreciation for plant-related differences (7.2 ) (6.9 ) Federal tax credits (1.5 ) (2.0 ) AFUDC equity — (0.3 ) Amortization of federal investment tax credits (0.3 ) (0.4 ) Stock compensation 1.0 (0.2 ) Officer compensation limitation 0.3 — Other 0.3 (1.4 ) Effective income tax rate 18.4 % 14.9 %

LEASES

LEASES	3 Months Ended
	Mar. 31, 2019
Leases [Abstract]
LEASES	LEASES The Evergy Companies lease office buildings, computer equipment, vehicles, rail cars, generating plant and other property and equipment, including rail cars to serve jointly-owned generating units where Westar Energy or KCP&L is the managing partner and is reimbursed by other joint-owners for its proportionate share of the costs. A contract is or contains a lease if the contract conveys the right to control the use of identified property, plant or equipment for a period of time in exchange for consideration. The Evergy Companies assess a contract as being or containing a lease if the contract identifies property, plant and equipment, provides the lessee the right to obtain substantially all of the economic benefits from use of the property, plant and equipment and provides the lessee the right to direct the use of the property, plant and equipment. The Evergy Companies have entered several agreements to purchase energy through renewable purchase power agreements accounted for as leases that commenced prior to the application of Topic 842. Due to the intermittent nature of renewable generation, these leases have significant variable lease payments not included in the initial and subsequent measurement of the lease liability. Variable lease payments are expensed as incurred. In addition, certain other contracts contain payment for activity that transfers a separate good or service such as utilities or common area maintenance. The Evergy Companies have elected a practical expedient permitted by GAAP to not separate such components of the lease from other lease components for all leases. The Evergy, Westar Energy and KCP&L leases have remaining terms ranging from 1 to 20 years, 1 to 20 years and 2 to 27 years, respectively. Leases that have original lease terms of twelve months or less are not recognized on the Evergy Companies’ balance sheets. Some leases have options to renew the lease or terminate early at the election of the Evergy Companies. Judgment is applied at lease commencement to determine the reasonably certain lease term based on then-current assumptions about use of the leased asset, market conditions and terms in the contract. The judgment applied to determine the lease term can significantly impact the measurement of the lease liability and right-of-use asset and lease classification. The Evergy Companies typically discount lease payments over the term of the lease using their incremental borrowing rates at lease commencement to measure its initial and subsequent lease liability. For leases that existed at the initial application of Topic 842, the Evergy Companies used the incremental borrowing rates that corresponded to the remaining lease term as of January 1, 2019. Leases may be classified as either operating leases or finance leases. The lease classification is based on assumptions of the lease term and discount rate, as discussed above, and the fair market value and economic life of the leased asset. Operating leases recognize a consistent expense each period over the lease term, while finance leases will result in the separate presentation of interest expense on the lease liability and amortization of the right-of-use asset. Finance leases are treated as operating leases for rate-making purposes and as such, the Evergy Companies defer to a regulatory asset or liability any material differences between expense recognition and the timing of payments in order to match what is being recovered in customer rates. The Evergy Companies’ lease expense is detailed in the following table. Three Months Ended March 31, 2019 Evergy Westar Energy KCP&L Finance lease costs (millions) Amortization of right-of-use assets $ 1.1 $ 1.0 $ — Interest on lease liabilities 0.7 0.6 — Operating lease costs 6.4 3.8 2.3 Short-term lease costs 0.8 0.1 0.7 Variable lease costs for renewable purchase power agreements 73.9 32.2 29.1 Total lease costs $ 82.9 $ 37.7 $ 32.1 Supplemental cash flow information related to the Evergy Companies' leases is detailed in the following table. Three Months Ended March 31, 2019 Evergy Westar Energy KCP&L Cash paid for amounts included in the measurement of lease liabilities: (millions) Operating cash flows from operating leases $ 5.8 $ 3.4 $ 2.4 Operating cash flows from finance leases 0.7 0.6 — Financing cash flows from finance leases 1.1 1.1 — Right-of-use assets obtained in exchange for new operating lease liabilities 2.2 — 2.2 Right-of-use assets obtained in exchange for new finance lease liabilities 2.3 2.3 — Finance Leases Right-of-use assets for finance leases are included in property, plant and equipment on the Evergy Companies’ balance sheets. Lease liabilities for finance leases are included in other current and other long-term liabilities. Payments for finance leases as of March 31, 2019 are detailed in the following table. Evergy Westar Energy KCP&L (millions) April 2019 through December 2019 $ 5.4 $ 5.1 $ 0.2 2020 7.0 6.6 0.2 2021 6.5 6.0 0.2 2022 5.7 5.2 0.2 2023 4.8 4.4 0.2 After 2023 48.4 46.4 1.0 Total finance lease payments 77.8 73.7 2.0 Amounts representing imputed interest (27.6 ) (26.4 ) (0.6 ) Present value of lease payments 50.2 47.3 1.4 Less: current portion (4.2 ) (4.0 ) (0.1 ) Total long-term obligations under finance leases $ 46.0 $ 43.3 $ 1.3 Weighted-average lease term (years) 15.4 15.8 9.4 Weighted-average discount rate 5.7 % 5.6 % 7.6 % Estimated future commitments under finance leases as of December 31, 2018 are detailed in the following table. Evergy Westar Energy KCP&L (millions) 2019 $ 6.4 $ 6.0 $ 0.2 2020 5.8 5.4 0.2 2021 5.3 4.9 0.2 2022 4.7 4.3 0.2 2023 4.0 3.6 0.2 After 2023 48.6 46.4 1.1 Total finance lease payments 74.8 70.6 2.1 Amounts representing imputed interest (25.8 ) (24.6 ) (0.6 ) Present value of net minimum lease payments under finance leases 49.0 46.0 1.5 Less: current portion (3.9 ) (3.7 ) (0.1 ) Total long-term obligations under finance leases $ 45.1 $ 42.3 $ 1.4 Operating Leases Right-of-use assets for operating leases are included in other long-term assets on the Evergy Companies’ balance sheets. Lease liabilities for operating leases are included in other current and other long-term liabilities. Lease payments for operating leases as of March 31, 2019 are detailed in the following table. Evergy Westar Energy KCP&L (millions) April 2019 through December 2019 $ 15.6 $ 9.5 $ 7.6 2020 18.7 10.2 10.6 2021 15.3 7.3 10.1 2022 12.4 5.1 9.3 2023 9.4 2.6 8.8 After 2023 52.4 2.8 91.3 Total operating lease payments 123.8 37.5 137.7 Amounts representing imputed interest (20.8 ) (2.7 ) (38.4 ) Present value of lease payments 103.0 34.8 99.3 Less: current portion (16.1 ) (10.5 ) (6.3 ) Total long-term obligations under operating leases $ 86.9 $ 24.3 $ 93.0 Weighted-average lease term (years) 9.3 4.2 16.2 Weighted-average discount rate 3.9 % 3.4 % 4.1 % Estimated future commitments under operating leases as of December 31, 2018 are detailed in the following table. Evergy Westar Energy KCP&L (millions) 2019 $ 24.2 $ 14.0 $ 10.2 2020 20.7 10.1 10.6 2021 18.4 8.1 10.3 2022 15.2 5.2 10.0 2023 12.4 2.8 9.6 After 2023 95.0 3.1 91.8 Total operating lease payments $ 185.9 $ 43.3 $ 142.5
LEASES	LEASES The Evergy Companies lease office buildings, computer equipment, vehicles, rail cars, generating plant and other property and equipment, including rail cars to serve jointly-owned generating units where Westar Energy or KCP&L is the managing partner and is reimbursed by other joint-owners for its proportionate share of the costs. A contract is or contains a lease if the contract conveys the right to control the use of identified property, plant or equipment for a period of time in exchange for consideration. The Evergy Companies assess a contract as being or containing a lease if the contract identifies property, plant and equipment, provides the lessee the right to obtain substantially all of the economic benefits from use of the property, plant and equipment and provides the lessee the right to direct the use of the property, plant and equipment. The Evergy Companies have entered several agreements to purchase energy through renewable purchase power agreements accounted for as leases that commenced prior to the application of Topic 842. Due to the intermittent nature of renewable generation, these leases have significant variable lease payments not included in the initial and subsequent measurement of the lease liability. Variable lease payments are expensed as incurred. In addition, certain other contracts contain payment for activity that transfers a separate good or service such as utilities or common area maintenance. The Evergy Companies have elected a practical expedient permitted by GAAP to not separate such components of the lease from other lease components for all leases. The Evergy, Westar Energy and KCP&L leases have remaining terms ranging from 1 to 20 years, 1 to 20 years and 2 to 27 years, respectively. Leases that have original lease terms of twelve months or less are not recognized on the Evergy Companies’ balance sheets. Some leases have options to renew the lease or terminate early at the election of the Evergy Companies. Judgment is applied at lease commencement to determine the reasonably certain lease term based on then-current assumptions about use of the leased asset, market conditions and terms in the contract. The judgment applied to determine the lease term can significantly impact the measurement of the lease liability and right-of-use asset and lease classification. The Evergy Companies typically discount lease payments over the term of the lease using their incremental borrowing rates at lease commencement to measure its initial and subsequent lease liability. For leases that existed at the initial application of Topic 842, the Evergy Companies used the incremental borrowing rates that corresponded to the remaining lease term as of January 1, 2019. Leases may be classified as either operating leases or finance leases. The lease classification is based on assumptions of the lease term and discount rate, as discussed above, and the fair market value and economic life of the leased asset. Operating leases recognize a consistent expense each period over the lease term, while finance leases will result in the separate presentation of interest expense on the lease liability and amortization of the right-of-use asset. Finance leases are treated as operating leases for rate-making purposes and as such, the Evergy Companies defer to a regulatory asset or liability any material differences between expense recognition and the timing of payments in order to match what is being recovered in customer rates. The Evergy Companies’ lease expense is detailed in the following table. Three Months Ended March 31, 2019 Evergy Westar Energy KCP&L Finance lease costs (millions) Amortization of right-of-use assets $ 1.1 $ 1.0 $ — Interest on lease liabilities 0.7 0.6 — Operating lease costs 6.4 3.8 2.3 Short-term lease costs 0.8 0.1 0.7 Variable lease costs for renewable purchase power agreements 73.9 32.2 29.1 Total lease costs $ 82.9 $ 37.7 $ 32.1 Supplemental cash flow information related to the Evergy Companies' leases is detailed in the following table. Three Months Ended March 31, 2019 Evergy Westar Energy KCP&L Cash paid for amounts included in the measurement of lease liabilities: (millions) Operating cash flows from operating leases $ 5.8 $ 3.4 $ 2.4 Operating cash flows from finance leases 0.7 0.6 — Financing cash flows from finance leases 1.1 1.1 — Right-of-use assets obtained in exchange for new operating lease liabilities 2.2 — 2.2 Right-of-use assets obtained in exchange for new finance lease liabilities 2.3 2.3 — Finance Leases Right-of-use assets for finance leases are included in property, plant and equipment on the Evergy Companies’ balance sheets. Lease liabilities for finance leases are included in other current and other long-term liabilities. Payments for finance leases as of March 31, 2019 are detailed in the following table. Evergy Westar Energy KCP&L (millions) April 2019 through December 2019 $ 5.4 $ 5.1 $ 0.2 2020 7.0 6.6 0.2 2021 6.5 6.0 0.2 2022 5.7 5.2 0.2 2023 4.8 4.4 0.2 After 2023 48.4 46.4 1.0 Total finance lease payments 77.8 73.7 2.0 Amounts representing imputed interest (27.6 ) (26.4 ) (0.6 ) Present value of lease payments 50.2 47.3 1.4 Less: current portion (4.2 ) (4.0 ) (0.1 ) Total long-term obligations under finance leases $ 46.0 $ 43.3 $ 1.3 Weighted-average lease term (years) 15.4 15.8 9.4 Weighted-average discount rate 5.7 % 5.6 % 7.6 % Estimated future commitments under finance leases as of December 31, 2018 are detailed in the following table. Evergy Westar Energy KCP&L (millions) 2019 $ 6.4 $ 6.0 $ 0.2 2020 5.8 5.4 0.2 2021 5.3 4.9 0.2 2022 4.7 4.3 0.2 2023 4.0 3.6 0.2 After 2023 48.6 46.4 1.1 Total finance lease payments 74.8 70.6 2.1 Amounts representing imputed interest (25.8 ) (24.6 ) (0.6 ) Present value of net minimum lease payments under finance leases 49.0 46.0 1.5 Less: current portion (3.9 ) (3.7 ) (0.1 ) Total long-term obligations under finance leases $ 45.1 $ 42.3 $ 1.4 Operating Leases Right-of-use assets for operating leases are included in other long-term assets on the Evergy Companies’ balance sheets. Lease liabilities for operating leases are included in other current and other long-term liabilities. Lease payments for operating leases as of March 31, 2019 are detailed in the following table. Evergy Westar Energy KCP&L (millions) April 2019 through December 2019 $ 15.6 $ 9.5 $ 7.6 2020 18.7 10.2 10.6 2021 15.3 7.3 10.1 2022 12.4 5.1 9.3 2023 9.4 2.6 8.8 After 2023 52.4 2.8 91.3 Total operating lease payments 123.8 37.5 137.7 Amounts representing imputed interest (20.8 ) (2.7 ) (38.4 ) Present value of lease payments 103.0 34.8 99.3 Less: current portion (16.1 ) (10.5 ) (6.3 ) Total long-term obligations under operating leases $ 86.9 $ 24.3 $ 93.0 Weighted-average lease term (years) 9.3 4.2 16.2 Weighted-average discount rate 3.9 % 3.4 % 4.1 % Estimated future commitments under operating leases as of December 31, 2018 are detailed in the following table. Evergy Westar Energy KCP&L (millions) 2019 $ 24.2 $ 14.0 $ 10.2 2020 20.7 10.1 10.6 2021 18.4 8.1 10.3 2022 15.2 5.2 10.0 2023 12.4 2.8 9.6 After 2023 95.0 3.1 91.8 Total operating lease payments $ 185.9 $ 43.3 $ 142.5

ORGANIZATION AND BASIS OF PRE_2

ORGANIZATION AND BASIS OF PRESENTATION (Policies)	3 Months Ended
	Mar. 31, 2019
Accounting Policies [Abstract]
Principles of Consolidation	Principles of Consolidation Westar Energy was determined to be the accounting acquirer in the merger and thus, the predecessor of Evergy. Therefore, Evergy's consolidated financial statements reflect the results of operations of Westar Energy for the three months ended March 31, 2018. Evergy had separate operations for the period beginning with the quarter ended June 30, 2018, and references to amounts for periods after the closing of the merger relate to Evergy. The results of Great Plains Energy's direct subsidiaries have been included in Evergy's results of operations from the date of the closing of the merger and thereafter. Each of Evergy's, Westar Energy's and KCP&L's consolidated financial statements includes the accounts of their subsidiaries and variable interest entities (VIEs) of which they are the primary beneficiary. Undivided interests in jointly-owned generation facilities are included on a proportionate basis. Intercompany transactions have been eliminated. The Evergy Companies assess financial performance and allocate resources on a consolidated basis (i.e., operate in one segment). Certain changes in classification and corresponding reclassification of prior period data were made in Evergy's, Westar Energy's and KCP&L's unaudited consolidated statements of income and comprehensive income and unaudited statements of cash flows for comparative purposes. Evergy reflects the classifications of Westar Energy as the accounting acquirer in the merger. These reclassifications did not affect Evergy's, Westar Energy's or KCP&L's net income or Evergy's, Westar Energy's or KCP&L's cash flows from operations, investing or financing.
Fuel Inventory and Supplies	Fuel Inventory and Supplies The Evergy Companies record fuel inventory and supplies at average cost.
Earnings Per Share	Earnings Per Share To compute basic earnings per share (EPS), Evergy divides net income attributable to Evergy, Inc. by the weighted average number of common shares outstanding. Diluted EPS includes the effect of issuable common shares resulting from restricted share units (RSUs), performance shares and restricted stock. Evergy computes the dilutive effects of potential issuances of common shares using the treasury stock method.
New Accounting Standards	New Accounting Standards Intangibles - Internal-Use Software In August 2018, the Financial Accounting Standards Board (FASB) issued Accounting Standards Update (ASU) No. 2018-15, Customer's Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract , which aligns the requirements for recording implementation costs incurred in a hosting arrangement that is a service contract with the requirements for capitalizing implementation costs incurred to develop or obtain internal-use software. An entity in a hosting arrangement that is a service contract will need to determine which project stage (that is, preliminary project stage, application development stage or post-implementation stage) an implementation activity relates. Costs for implementation activities in the application development stage are recorded as a prepaid asset depending on the nature of the costs, while costs incurred during the preliminary project and post-implementation stages are expensed as the activities occur. Costs that are recorded to a prepaid asset are to be expensed over the term of the hosting arrangement. The new guidance is effective for annual periods beginning after December 15, 2019 and interim periods within those fiscal years. The new guidance can be applied either retrospectively or prospectively to all implementation costs incurred after the date of adoption. Early adoption is permitted. The Evergy Companies early adopted ASU No. 2018-15 prospectively as of January 1, 2019. The adoption of ASU No. 2018-15 did not have a material impact on the Evergy Companies. Leases In February 2016, the FASB issued ASU No. 2016-02, Leases , which requires an entity that is a lessee to record a right-of-use asset and a lease liability for lease payments on the balance sheet for all leases with terms longer than 12 months. Leases will be classified as either finance or operating, with classification affecting the pattern of expense recognition in the income statement. Lessor accounting remains largely unchanged. In January 2018, the FASB issued ASU No. 2018-01, Leases: Land Easement Practical Expedient for Transition to Topic 842 , which permits entities to elect an optional transition practical expedient to not evaluate, under Topic 842, land easements that exist or expired before the entity's adoption of Topic 842 and that were not previously accounted for as leases under Topic 840. In July 2018, the FASB issued ASU No. 2018-10, Codification Improvements to Topic 842, Leases , which updates narrow aspects of the guidance issued in ASU No. 2016-02. Also in July 2018, the FASB issued ASU No. 2018-11, Leases: Targeted Improvements , which provides an optional transition method that allows entities to initially apply Topic 842 at the adoption date and recognize a cumulative-effect adjustment to the opening balance of retained earnings in the period of adoption without restating prior periods. In December 2018, the FASB issued ASU No. 2018-20, Leases: Narrow-Scope Improvements for Lessors , which is expected to reduce a lessor's implementation and ongoing costs associated with applying ASU No. 2016-02. In March 2019, the FASB issued ASU No. 2019-01, Leases: Codification Improvements , which clarifies certain lessor accounting and interim reporting requirements. ASU No. 2016-02 and the subsequent amendments are effective for interim and annual periods beginning after December 15, 2018, with early adoption permitted, and requires a modified retrospective transition approach with an option to either adjust or not adjust comparative periods. The Evergy Companies adopted the new guidance on January 1, 2019, without adjusting comparative periods for all leases existing as of January 1, 2019, by electing the optional transition method permitted by ASU No. 2018-11. As a result, Evergy, Westar Energy and KCP&L recorded an increase to assets and liabilities of approximately $110 million , $40 million and $80 million , respectively, as of January 1, 2019. Westar Energy and KCP&L have certain lease transactions between them for which the related assets and liabilities are eliminated at consolidated Evergy. The adoption of Topic 842 did not have a material impact on the Evergy Companies' consolidated statements of income and comprehensive income and there was no cumulative-effect adjustment recorded to the opening balance of retained earnings. The Evergy Companies also elected a practical expedient to forgo reassessing existing or expired contracts as leases to determine whether each is in scope of Topic 842 and to forgo reassessing lease classification for existing and expired leases.

ORGANIZATION AND BASIS OF PRE_3

ORGANIZATION AND BASIS OF PRESENTATION (Tables)	3 Months Ended
	Mar. 31, 2019
Accounting Policies [Abstract]
Summary of Reclassifications	The table below summarizes KCP&L's reclassifications related to operating and investing activities for its consolidated statement of cash flows for the three months ended March 31, 2018 . As Previously Filed As Recast CASH FLOWS FROM (USED IN) OPERATING ACTIVITIES: (millions) Adjustments to reconcile income to net cash from operating activities: Amortization of other $ 6.6 $ — Amortization of deferred refueling outage — 3.9 Deferred income taxes, net 5.6 — Investment tax credit amortization (0.3 ) — Net deferred income taxes and credits — 5.3 Other (a) 3.8 0.2 Changes in working capital items: Fuel inventory and supplies — (2.8 ) Fuel inventories (a) (1.0 ) — Materials and supplies (a) (1.8 ) — Prepaid expenses and other current assets — (2.5 ) Accrued interest (a) 8.3 — Other current liabilities — (1.8 ) Changes in other assets — 16.5 Changes in other liabilities — 13.5 Deferred refueling outage costs (a) 0.9 — Pension and post-retirement benefit obligations (a) 9.0 — Fuel recovery mechanisms (a) 1.2 — Total reclassifications $ 32.3 $ 32.3 CASH FLOWS FROM (USED IN) INVESTING ACTIVITIES: Additions to property, plant and equipment $ — $ (100.6 ) Utility capital expenditures (93.5 ) — Allowance for borrowed funds used during construction (2.0 ) — Other investing activities (4.5 ) 0.6 Total reclassifications $ (100.0 ) $ (100.0 ) (a) Previously reported within Note 4 to the consolidated financial statements of the Great Plains Energy and KCP&L combined First Quarter 2018 Quarterly Report on Form 10-Q.
Schedule of Fuel Inventory and Supplies	The following table separately states the balances for fuel inventory and supplies. March 31 December 31 2019 2018 Evergy (millions) Fuel inventory $ 132.2 $ 168.9 Supplies 334.3 342.1 Fuel inventory and supplies $ 466.5 $ 511.0 Westar Energy Fuel inventory $ 74.2 $ 87.8 Supplies 180.8 189.0 Fuel inventory and supplies $ 255.0 $ 276.8 KCP&L Fuel inventory $ 39.2 $ 57.8 Supplies 120.1 119.8 Fuel inventory and supplies $ 159.3 $ 177.6
Summary of Property, Plant and Equipment	The following tables summarize the property, plant and equipment of Evergy, Westar Energy and KCP&L. March 31, 2019 Evergy Westar Energy KCP&L (millions) Electric plant in service $ 27,161.1 $ 13,263.5 $ 10,546.0 Electric plant acquisition adjustment 740.6 740.6 — Accumulated depreciation (9,856.2 ) (4,721.2 ) (4,083.5 ) Plant in service 18,045.5 9,282.9 6,462.5 Construction work in progress 635.7 365.0 173.2 Nuclear fuel, net 155.9 77.5 78.4 Plant to be retired, net (a) 1.0 1.0 — Property, plant and equipment, net $ 18,838.1 $ 9,726.4 $ 6,714.1 December 31, 2018 Evergy Westar Energy KCP&L (millions) Electric plant in service $ 26,916.7 $ 13,176.7 $ 10,439.1 Electric plant acquisition adjustment 740.6 740.6 — Accumulated depreciation (9,694.1 ) (4,642.8 ) (4,022.4 ) Plant in service 17,963.2 9,274.5 6,416.7 Construction work in progress 685.2 376.7 204.4 Nuclear fuel, net 133.1 66.1 67.0 Plant to be retired, net (a) 1.0 1.0 — Property, plant and equipment, net $ 18,782.5 $ 9,718.3 $ 6,688.1 (a) As of March 31, 2019 and December 31, 2018 , represents the planned retirement of Westar Energy analog meters prior to the end of their remaining useful lives.
Schedule of Other Nonoperating Income (Expense)	The table below shows the detail of other expense for each of the Evergy Companies. Three Months Ended March 31 2019 2018 Evergy (millions) Non-service cost component of net benefit cost $ (13.1 ) $ (5.7 ) Other (6.3 ) (4.9 ) Other expense $ (19.4 ) $ (10.6 ) Westar Energy Non-service cost component of net benefit cost $ (4.4 ) $ (5.7 ) Other (6.2 ) (4.9 ) Other expense $ (10.6 ) $ (10.6 ) KCP&L (a) Non-service cost component of net benefit cost $ (5.1 ) $ (6.7 ) Other 0.1 (1.2 ) Other expense $ (5.0 ) $ (7.9 ) (a) KCP&L amounts are not included in consolidated Evergy for the three months ended March 31, 2018.
Schedule of Earnings Per Share, Basic and Diluted	The following table reconciles Evergy's basic and diluted EPS. Three Months Ended March 31 2019 2018 Income (millions, except per share amounts) Net income $ 103.4 $ 62.9 Less: net income attributable to noncontrolling interests 3.9 2.4 Net income attributable to Evergy, Inc. 99.5 60.5 Common Shares Outstanding Weighted average number of common shares outstanding - basic 252.8 142.6 Add: effect of dilutive securities 0.2 0.1 Weighted average number of common shares outstanding - dilutive 253.0 142.7 Basic and Diluted EPS $ 0.39 $ 0.42
Supplemental Cash Flow Information	Supplemental Cash Flow Information Three Months Ended March 31 2019 2018 Evergy (millions) Cash paid for (received from): Interest, net of amounts capitalized $ 59.3 $ 33.0 Interest of VIEs 1.0 1.3 Income taxes, net of refunds (0.1 ) (0.2 ) Non-cash investing transactions: Property, plant and equipment additions 47.1 29.8 Non-cash financing transactions: Issuance of stock for compensation and reinvested dividends 0.5 0.1 Westar Energy Cash paid for (received from): Interest, net of amounts capitalized $ 32.6 $ 33.0 Interest of VIEs 1.0 1.3 Income taxes, net of refunds — (0.2 ) Non-cash investing transactions: Property, plant and equipment additions 27.1 29.8 Non-cash financing transactions: Issuance of stock for compensation and reinvested dividends — 0.1 KCP&L (a) Cash paid for (received from): Interest, net of amounts capitalized $ 19.6 $ 22.7 Non-cash investing transactions: Property, plant and equipment additions 15.9 20.9 (a) KCP&L amounts are not included in consolidated Evergy for the three months ended March 31, 2018.
Unaudited Pro Forma Financial Information	The unaudited pro forma financial information has been presented for illustrative purposes only and is not necessarily indicative of the consolidated results of operations that would have been achieved or the future consolidated results of operations of Evergy. Three Months Ended March 31, 2018 (millions, except per share amounts) Operating revenues $ 1,184.1 Net income attributable to Evergy, Inc. 91.9 Basic earnings per common share $ 0.34 Diluted earnings per common share $ 0.34

REVENUE (Tables)

REVENUE (Tables)	3 Months Ended
	Mar. 31, 2019
Revenue from Contract with Customer [Abstract]
Disaggregation of Revenue	Evergy's, Westar Energy's and KCP&L's revenues disaggregated by customer class are summarized in the following tables. Three Months Ended March 31, 2019 Evergy Westar Energy KCP&L Revenues (millions) Residential $ 451.7 $ 192.3 $ 164.2 Commercial 413.5 164.3 183.8 Industrial 147.0 98.4 29.7 Other retail 9.8 5.1 2.6 Total electric retail $ 1,022.0 $ 460.1 $ 380.3 Wholesale 83.1 61.3 18.1 Transmission 76.7 69.2 3.1 Industrial steam and other 3.3 1.7 1.4 Total revenue from contracts with customers $ 1,185.1 $ 592.3 $ 402.9 Other 31.8 4.5 22.5 Operating revenues $ 1,216.9 $ 596.8 $ 425.4 Three Months Ended March 31, 2018 Evergy Westar Energy KCP&L (a) Revenues (millions) Residential $ 180.3 $ 180.3 $ 154.9 Commercial 155.4 155.4 181.8 Industrial 93.5 93.5 32.2 Other retail 4.2 4.2 2.7 Total electric retail $ 433.4 $ 433.4 $ 371.6 Wholesale 94.2 94.2 3.1 Transmission 71.9 71.9 3.3 Other 1.8 1.8 — Total revenue from contracts with customers $ 601.3 $ 601.3 $ 378.0 Other (1.1 ) (1.1 ) 19.1 Operating revenues $ 600.2 $ 600.2 $ 397.1 (a) KCP&L amounts are not included in consolidated Evergy for the three months ended March 31, 2018.

RECEIVABLES (Tables)

RECEIVABLES (Tables)	3 Months Ended
	Mar. 31, 2019
Receivables [Abstract]
Schedule of Receivables	The Evergy Companies' receivables are detailed in the following table. March 31 December 31 2019 2018 Evergy (millions) Customer accounts receivable - billed $ 15.0 $ 16.7 Customer accounts receivable - unbilled 82.1 91.2 Other receivables 77.5 95.0 Allowance for doubtful accounts (9.8 ) (9.2 ) Total $ 164.8 $ 193.7 Westar Energy Customer accounts receivable - billed $ — $ — Customer accounts receivable - unbilled 33.4 16.6 Other receivables 61.2 71.6 Allowance for doubtful accounts (4.2 ) (3.9 ) Total $ 90.4 $ 84.3 KCP&L Customer accounts receivable - billed $ 8.0 $ 7.8 Customer accounts receivable - unbilled 25.9 42.9 Other receivables 11.9 15.8 Allowance for doubtful accounts (4.0 ) (3.8 ) Total $ 41.8 $ 62.7
Summary of Bad Debt Expense	The Evergy Companies recorded bad debt expense related to contracts with customers as summarized in the following table. Three Months Ended March 31 2019 2018 (millions) Evergy $ 4.0 $ 4.0 Westar Energy (0.3 ) 4.0 KCP&L (a) 2.8 1.7 (a) KCP&L amounts are not included in consolidated Evergy for the three months ended March 31, 2018.

PENSION PLANS AND POST-RETIRE_2

PENSION PLANS AND POST-RETIREMENT BENEFITS (Tables)	3 Months Ended
	Mar. 31, 2019
Retirement Benefits [Abstract]
Schedule of Net Benefit Costs	The following tables provide the components of net periodic benefit costs prior to the effects of capitalization and sharing with joint owners of power plants. Pension Benefits Post-Retirement Benefits Three Months Ended March 31, 2019 Evergy Westar Energy KCP&L Evergy Westar Energy KCP&L Components of net periodic benefit costs (millions) Service cost $ 19.1 $ 7.3 $ 11.8 $ 0.6 $ 0.3 $ 0.3 Interest cost 27.5 13.4 14.1 2.6 1.4 1.2 Expected return on plan assets (27.1 ) (13.7 ) (12.3 ) (2.4 ) (1.7 ) (0.7 ) Prior service cost 0.5 0.4 0.2 0.1 0.1 — Recognized net actuarial (gain)/loss 6.9 6.4 12.2 (0.3 ) (0.1 ) (0.4 ) Net periodic benefit costs before regulatory adjustment and intercompany allocations 26.9 13.8 26.0 0.6 — 0.4 Regulatory adjustment (0.1 ) 0.5 (0.6 ) (0.7 ) (0.8 ) 0.1 Intercompany allocations — — (6.9 ) — — (0.1 ) Net periodic benefit costs $ 26.8 $ 14.3 $ 18.5 $ (0.1 ) $ (0.8 ) $ 0.4 Pension Benefits Post-Retirement Benefits Three Months Ended March 31, 2018 Evergy Westar Energy KCP&L (a) Evergy Westar Energy KCP&L (a) Components of net periodic benefit costs (millions) Service cost $ 8.0 $ 8.0 $ 12.2 $ 0.3 $ 0.3 $ 0.5 Interest cost 12.7 12.7 12.7 1.2 1.2 1.2 Expected return on plan assets (14.0 ) (14.0 ) (13.9 ) (1.7 ) (1.7 ) (0.7 ) Prior service cost 0.2 0.2 0.2 0.1 0.1 — Recognized net actuarial (gain)/loss 8.2 8.2 11.4 (0.1 ) (0.1 ) — Net periodic benefit costs before regulatory adjustment and intercompany allocations 15.1 15.1 22.6 (0.2 ) (0.2 ) 1.0 Regulatory adjustment 2.8 2.8 0.4 (0.4 ) (0.4 ) (0.1 ) Intercompany allocations — — (5.5 ) — — (0.3 ) Net periodic benefit costs $ 17.9 $ 17.9 $ 17.5 $ (0.6 ) $ (0.6 ) $ 0.6 (a) KCP&L amounts are not included in consolidated Evergy for the three months ended March 31, 2018 .

SHORT-TERM BORROWINGS AND SHO_2

SHORT-TERM BORROWINGS AND SHORT-TERM BANK LINES OF CREDIT (Tables)	3 Months Ended
	Mar. 31, 2019
Debt Disclosure [Abstract]
Schedule of short-term debt	The following table summarizes the committed credit facilities (excluding receivable sale facilities discussed in Note 3 and Evergy's term loan credit agreement discussed below) available to the Evergy Companies as of March 31, 2019 and December 31, 2018 . Amounts Drawn Credit Facility Commercial Paper Letters of Credit Cash Borrowings Available Borrowings Weighted Average Interest Rate on Short-Term Borrowings March 31, 2019 (millions) Evergy, Inc. $ 450.0 n/a $ 1.0 $ 100.0 $ 349.0 3.73% Westar Energy 1,000.0 413.8 18.3 — 567.9 2.77% KCP&L 600.0 176.0 2.7 — 421.3 2.89% GMO 450.0 121.2 2.1 — 326.7 2.75% Evergy $ 2,500.0 $ 711.0 $ 24.1 $ 100.0 $ 1,664.9 December 31, 2018 Evergy, Inc. $ 450.0 n/a $ 1.0 $ — $ 449.0 —% Westar Energy 1,000.0 411.7 18.3 — 570.0 3.08% KCP&L 600.0 176.9 2.7 — 420.4 2.95% GMO 450.0 150.0 2.1 — 297.9 3.00% Evergy $ 2,500.0 $ 738.6 $ 24.1 $ — $ 1,737.3

FAIR VALUE MEASUREMENTS (Tables

FAIR VALUE MEASUREMENTS (Tables)	3 Months Ended
	Mar. 31, 2019
Fair Value Disclosures [Abstract]
Carrying value and fair value of debt instruments	The Evergy Companies measure the fair value of long-term debt using Level 2 measurements available as of the measurement date. The book value and fair value of the Evergy Companies' long-term debt and long-term debt of variable interest entities is summarized in the following table. March 31, 2019 December 31, 2018 Book Value Fair Value Book Value Fair Value Long-term debt (a) (millions) Evergy (b) $ 7,827.0 $ 8,130.5 $ 7,341.7 $ 7,412.1 Westar Energy 3,690.0 3,884.4 3,689.8 3,771.3 KCP&L 2,924.6 3,130.2 2,530.1 2,637.5 Long-term debt of variable interest entities (a) Evergy $ 51.1 $ 50.9 $ 81.4 $ 81.3 Westar Energy 51.1 50.9 81.4 81.3 (a) Includes current maturities. (b) Book value as of March 31, 2019 and December 31, 2018 , includes $136.8 million and $144.8 million , respectively, of fair value adjustments recorded in connection with purchase accounting for the Great Plains Energy and Westar Energy merger, which are not part of future principal payments and will amortize over the remaining life of the associated debt instrument.
Fair value of assets and liabilities	The following tables include the Evergy Companies' balances of financial assets and liabilities measured at fair value on a recurring basis. Description March 31, 2019 Level 1 Level 2 Level 3 NAV Westar Energy (millions) Assets Nuclear decommissioning trust (a) Domestic equity funds $ 80.1 $ 73.6 $ — $ — $ 6.5 International equity funds 46.5 46.5 — — — Core bond fund 34.6 34.6 — — — High-yield bond fund 20.6 20.6 — — — Emerging markets bond fund 16.4 16.4 — — — Combination debt/equity/other fund 14.7 14.7 — — — Alternative investments fund 23.3 — — — 23.3 Real estate securities fund 12.0 — — — 12.0 Cash equivalents 0.2 0.2 — — — Total nuclear decommissioning trust 248.4 206.6 — — 41.8 Rabbi trust Core bond fund 24.7 — — — 24.7 Combination debt/equity/other fund 6.2 — — — 6.2 Cash equivalents 0.2 0.2 — — — Total rabbi trust 31.1 0.2 — — 30.9 Total $ 279.5 $ 206.8 $ — $ — $ 72.7 KCP&L Assets Nuclear decommissioning trust (a) Equity securities $ 188.3 $ 188.3 $ — $ — $ — Debt securities U.S. Treasury 46.0 46.0 — — — U.S. Agency 0.4 — 0.4 — — State and local obligations 2.1 — 2.1 — — Corporate bonds 30.6 — 30.6 — — Foreign governments 0.1 — 0.1 — — Cash equivalents 2.9 2.9 — — — Other (0.5 ) — (0.5 ) — — Total nuclear decommissioning trust 269.9 237.2 32.7 — — Self-insured health plan trust (b) Equity securities 0.5 0.5 — — — Debt securities 4.3 0.4 3.9 — — Cash and cash equivalents 6.7 6.7 — — — Other 1.1 — 1.1 — — Total self-insured health plan trust 12.6 7.6 5.0 — — Total $ 282.5 $ 244.8 $ 37.7 $ — $ — Other Evergy Assets Rabbi trusts Fixed income fund $ 13.1 $ — $ — $ — $ 13.1 Cash and cash equivalents 0.4 0.4 — — — Total rabbi trusts $ 13.5 $ 0.4 $ — $ — $ 13.1 Liabilities Interest rate swaps (c) $ 19.2 $ — $ 19.2 $ — $ — Total $ 19.2 $ — $ 19.2 $ — $ — Evergy Assets Nuclear decommissioning trust (a) $ 518.3 $ 443.8 $ 32.7 $ — $ 41.8 Rabbi trusts 44.6 0.6 — — 44.0 Self-insured health plan trust (b) 12.6 7.6 5.0 — — Total $ 575.5 $ 452.0 $ 37.7 $ — $ 85.8 Liabilities Interest rate swaps (c) $ 19.2 $ — $ 19.2 $ — $ — Total $ 19.2 $ — $ 19.2 $ — $ — Description December 31, 2018 Level 1 Level 2 Level 3 NAV Westar Energy (millions) Assets Nuclear decommissioning trust (a) Domestic equity funds $ 70.6 $ 63.9 $ — $ — $ 6.7 International equity funds 36.2 36.2 — — — Core bond fund 37.5 37.5 — — — High-yield bond fund 18.9 18.9 — — — Emerging markets bond fund 15.4 15.4 — — — Combination debt/equity/other fund 12.9 12.9 — — — Alternative investments fund 24.1 — — — 24.1 Real estate securities fund 11.8 — — — 11.8 Cash equivalents 0.1 0.1 — — — Total nuclear decommissioning trust 227.5 184.9 — — 42.6 Rabbi trust Core bond fund 24.8 — — — 24.8 Combination debt/equity/other fund 5.6 — — — 5.6 Cash equivalents 0.2 0.2 — — — Total rabbi trust 30.6 0.2 — — 30.4 Total $ 258.1 $ 185.1 $ — $ — $ 73.0 KCP&L Assets Nuclear decommissioning trust (a) Equity securities $ 166.6 $ 166.6 $ — $ — $ — Debt securities U.S. Treasury 42.1 42.1 — — — U.S. Agency 0.4 — 0.4 — — State and local obligations 2.1 — 2.1 — — Corporate bonds 30.9 — 30.9 — — Foreign governments 0.1 — 0.1 — — Cash equivalents 1.7 1.7 — — — Other 0.7 0.7 — — — Total nuclear decommissioning trust 244.6 211.1 33.5 — — Self-insured health plan trust (b) Equity securities 0.5 0.5 — — — Debt securities 3.9 0.3 3.6 — — Cash and cash equivalents 8.0 8.0 — — — Total self-insured health plan trust 12.4 8.8 3.6 — — Total $ 257.0 $ 219.9 $ 37.1 $ — $ — Other Evergy Assets Rabbi trusts Fixed income fund $ 13.2 $ — $ — $ — $ 13.2 Total rabbi trusts $ 13.2 $ — $ — $ — $ 13.2 Liabilities Interest rate swaps (c) $ 5.4 $ — $ 5.4 $ — $ — Total $ 5.4 $ — $ 5.4 $ — $ — Evergy Assets Nuclear decommissioning trust (a) $ 472.1 $ 396.0 $ 33.5 $ — $ 42.6 Rabbi trust 43.8 0.2 — — 43.6 Self-insured health plan trust (b) 12.4 8.8 3.6 — — Total $ 528.3 $ 405.0 $ 37.1 $ — $ 86.2 Liabilities Interest rate swaps (c) $ 5.4 $ — $ 5.4 $ — $ — Total $ 5.4 $ — $ 5.4 $ — $ — (a) Fair value is based on quoted market prices of the investments held by the trust and/or valuation models. (b) Fair value is based on quoted market prices of the investments held by the trust. Debt securities classified as Level 1 are comprised of U.S. Treasury securities. Debt securities classified as Level 2 are comprised of corporate bonds, U.S. Agency, state and local obligations, and other asset-backed securities. (c) The fair value of interest rate swaps are determined by calculating the net present value of expected payments and receipts under the interest rate swaps using observable market inputs including interest rates and LIBOR swap rates.
Fair value investments, entities that calculate NAV	The following table provides additional information on these Evergy and Westar Energy investments. March 31, 2019 December 31, 2018 March 31, 2019 Fair Unfunded Fair Unfunded Redemption Length of Value Commitments Value Commitments Frequency Settlement Westar Energy (millions) Nuclear decommissioning trust: Domestic equity funds $ 6.5 $ 4.0 $ 6.7 $ 4.3 (a) (a) Alternative investments fund (b) 23.3 — 24.1 — Quarterly 65 days Real estate securities fund (b) 12.0 — 11.8 — Quarterly 65 days Total $ 41.8 $ 4.0 $ 42.6 $ 4.3 Rabbi trust: Core bond fund $ 24.7 $ — $ 24.8 $ — (c) (c) Combination debt/equity/other fund 6.2 — 5.6 — (c) (c) Total $ 30.9 $ — $ 30.4 $ — Other Evergy Rabbi trusts: Fixed income fund $ 13.1 $ — $ 13.2 $ — (c) (c) Total Evergy investments at NAV $ 85.8 $ 4.0 $ 86.2 $ 4.3 (a) This investment is in five long-term private equity funds that do not permit early withdrawal. Investments in these funds cannot be distributed until the underlying investments have been liquidated, which may take years from the date of initial liquidation. Three funds have begun to make distributions. The initial investment in the fourth and fifth fund occurred in the second quarter of 2016 and first quarter of 2018, respectively. The fourth fund's term is 15 years , subject to the general partner's right to extend the term for up to three additional one -year periods. The fifth fund's term will be 15 years after the initial closing date, subject to additional extensions approved by the Advisory Committee to provide for an orderly liquidation of fund investments and dissolution of the fund. (b) There is a holdback on final redemptions. (c) This investment can be redeemed immediately and is not subject to any restrictions on redemptions.
Fair value recurring gain (loss) included in earnings	The following table summarizes the net unrealized gains (losses) for the Evergy Companies' nuclear decommissioning trusts and rabbi trusts. Three Months Ended March 31 2019 2018 Westar Energy (millions) Nuclear decommissioning trust - equity securities $ 17.2 $ (11.7 ) Rabbi trust 1.3 (0.5 ) Total $ 18.5 $ (12.2 ) KCP&L (a) Nuclear decommissioning trust - equity securities $ 20.7 $ (3.6 ) Nuclear decommissioning trust - debt securities 2.1 (1.6 ) Total $ 22.8 $ (5.2 ) Evergy Nuclear decommissioning trust - equity securities $ 37.9 $ (11.7 ) Nuclear decommissioning trust - debt securities 2.1 — Rabbi trusts 0.5 (0.5 ) Total $ 40.5 $ (12.2 ) (a) KCP&L amounts are not included in consolidated Evergy for the three months ended March 31, 2018 .

RELATED PARTY TRANSACTIONS AN_2

RELATED PARTY TRANSACTIONS AND RELATIONSHIPS (Tables)	3 Months Ended
	Mar. 31, 2019
Related Party Transactions [Abstract]
Schedule of related party receivables and payables	The following table summarizes Westar Energy's and KCP&L's related party net receivables and payables. March 31 December 31 2019 2018 Westar Energy (millions) Net receivable from GMO $ 2.5 $ 2.6 Net payable to KCP&L (8.3 ) (13.5 ) Net payable to Evergy (0.5 ) (1.4 ) KCP&L Net receivable from GMO $ 53.6 $ 72.6 Net receivable from Westar Energy 8.3 13.5 Net receivable from Evergy 19.3 15.7

TAXES (Tables)

TAXES (Tables)	3 Months Ended
	Mar. 31, 2019
Income Tax Disclosure [Abstract]
Schedule of Components of Income Tax Expense (Benefit)	Components of income tax expense are detailed in the following tables. Evergy Three Months Ended March 31 2019 2018 Current income taxes (millions) Federal $ 11.9 $ 0.2 State (0.6 ) — Total 11.3 0.2 Deferred income taxes Federal (7.3 ) 5.9 State 6.3 3.7 Total (1.0 ) 9.6 Investment tax credit amortization (1.0 ) (0.6 ) Income tax expense $ 9.3 $ 9.2 Westar Energy Three Months Ended March 31 2019 2018 Current income taxes (millions) Federal $ 10.4 $ 0.2 State 0.4 — Total 10.8 0.2 Deferred income taxes Federal (3.2 ) 5.9 State 3.6 3.7 Total 0.4 9.6 Investment tax credit amortization (0.7 ) (0.6 ) Income tax expense $ 10.5 $ 9.2 KCP&L (a) Three Months Ended March 31 2019 2018 Current income taxes (millions) Federal $ 7.9 $ (1.3 ) State 0.8 (0.5 ) Total 8.7 (1.8 ) Deferred income taxes Federal (5.2 ) 3.6 State 0.4 2.0 Total (4.8 ) 5.6 Investment tax credit amortization (0.2 ) (0.3 ) Income tax expense $ 3.7 $ 3.5 (a) KCP&L amounts are not included in consolidated Evergy for the three months ended March 31, 2018.
Schedule of Effective Income Tax Rate Reconciliation	Effective income tax rates reflected in the financial statements and the reasons for their differences from the statutory federal rates are detailed in the following tables. Evergy Three Months Ended March 31 2019 2018 Federal statutory income tax rate 21.0 % 21.0 % Effect of: COLI policies (1.8 ) (3.1 ) State income taxes 4.6 4.2 Flow through depreciation for plant-related differences (4.4 ) 0.9 Federal tax credits (3.9 ) (9.5 ) Non-controlling interest (0.3 ) (0.5 ) AFUDC equity — (0.2 ) Amortization of federal investment tax credits (0.5 ) (0.6 ) Valuation allowance (7.0 ) 2.1 Stock compensation 0.1 (1.1 ) Officer compensation limitation 0.2 — Other 0.2 (0.5 ) Effective income tax rate 8.2 % 12.7 % Westar Energy Three Months Ended March 31 2019 2018 Federal statutory income tax rate 21.0 % 21.0 % Effect of: COLI policies (3.2 ) (3.1 ) State income taxes 5.0 4.2 Flow through depreciation for plant-related differences (0.1 ) 0.9 Federal tax credits (6.1 ) (9.5 ) Non-controlling interest (0.6 ) (0.5 ) AFUDC equity (0.1 ) (0.2 ) Amortization of federal investment tax credits (0.7 ) (0.6 ) Valuation allowance (2.1 ) 2.1 Stock compensation (0.1 ) (1.1 ) Other 0.3 (0.5 ) Effective income tax rate 13.3 % 12.7 % KCP&L Three Months Ended March 31 2019 2018 Federal statutory income tax rate 21.0 % 21.0 % Effect of: COLI policies (0.1 ) — State income taxes 4.9 5.1 Flow through depreciation for plant-related differences (7.2 ) (6.9 ) Federal tax credits (1.5 ) (2.0 ) AFUDC equity — (0.3 ) Amortization of federal investment tax credits (0.3 ) (0.4 ) Stock compensation 1.0 (0.2 ) Officer compensation limitation 0.3 — Other 0.3 (1.4 ) Effective income tax rate 18.4 % 14.9 %

LEASES (Tables)

LEASES (Tables)	3 Months Ended
	Mar. 31, 2019
Leases [Abstract]
Schedule of lease expense	The Evergy Companies’ lease expense is detailed in the following table. Three Months Ended March 31, 2019 Evergy Westar Energy KCP&L Finance lease costs (millions) Amortization of right-of-use assets $ 1.1 $ 1.0 $ — Interest on lease liabilities 0.7 0.6 — Operating lease costs 6.4 3.8 2.3 Short-term lease costs 0.8 0.1 0.7 Variable lease costs for renewable purchase power agreements 73.9 32.2 29.1 Total lease costs $ 82.9 $ 37.7 $ 32.1 Supplemental cash flow information related to the Evergy Companies' leases is detailed in the following table. Three Months Ended March 31, 2019 Evergy Westar Energy KCP&L Cash paid for amounts included in the measurement of lease liabilities: (millions) Operating cash flows from operating leases $ 5.8 $ 3.4 $ 2.4 Operating cash flows from finance leases 0.7 0.6 — Financing cash flows from finance leases 1.1 1.1 — Right-of-use assets obtained in exchange for new operating lease liabilities 2.2 — 2.2 Right-of-use assets obtained in exchange for new finance lease liabilities 2.3 2.3 —
Schedule of payments for finance leases	Payments for finance leases as of March 31, 2019 are detailed in the following table. Evergy Westar Energy KCP&L (millions) April 2019 through December 2019 $ 5.4 $ 5.1 $ 0.2 2020 7.0 6.6 0.2 2021 6.5 6.0 0.2 2022 5.7 5.2 0.2 2023 4.8 4.4 0.2 After 2023 48.4 46.4 1.0 Total finance lease payments 77.8 73.7 2.0 Amounts representing imputed interest (27.6 ) (26.4 ) (0.6 ) Present value of lease payments 50.2 47.3 1.4 Less: current portion (4.2 ) (4.0 ) (0.1 ) Total long-term obligations under finance leases $ 46.0 $ 43.3 $ 1.3 Weighted-average lease term (years) 15.4 15.8 9.4 Weighted-average discount rate 5.7 % 5.6 % 7.6 %
Schedule of future commitments under finance leases	Estimated future commitments under finance leases as of December 31, 2018 are detailed in the following table. Evergy Westar Energy KCP&L (millions) 2019 $ 6.4 $ 6.0 $ 0.2 2020 5.8 5.4 0.2 2021 5.3 4.9 0.2 2022 4.7 4.3 0.2 2023 4.0 3.6 0.2 After 2023 48.6 46.4 1.1 Total finance lease payments 74.8 70.6 2.1 Amounts representing imputed interest (25.8 ) (24.6 ) (0.6 ) Present value of net minimum lease payments under finance leases 49.0 46.0 1.5 Less: current portion (3.9 ) (3.7 ) (0.1 ) Total long-term obligations under finance leases $ 45.1 $ 42.3 $ 1.4
Schedule of lease payments for operating leases	Lease payments for operating leases as of March 31, 2019 are detailed in the following table. Evergy Westar Energy KCP&L (millions) April 2019 through December 2019 $ 15.6 $ 9.5 $ 7.6 2020 18.7 10.2 10.6 2021 15.3 7.3 10.1 2022 12.4 5.1 9.3 2023 9.4 2.6 8.8 After 2023 52.4 2.8 91.3 Total operating lease payments 123.8 37.5 137.7 Amounts representing imputed interest (20.8 ) (2.7 ) (38.4 ) Present value of lease payments 103.0 34.8 99.3 Less: current portion (16.1 ) (10.5 ) (6.3 ) Total long-term obligations under operating leases $ 86.9 $ 24.3 $ 93.0 Weighted-average lease term (years) 9.3 4.2 16.2 Weighted-average discount rate 3.9 % 3.4 % 4.1 %
Schedule of future commitments under operating leases	Estimated future commitments under operating leases as of December 31, 2018 are detailed in the following table. Evergy Westar Energy KCP&L (millions) 2019 $ 24.2 $ 14.0 $ 10.2 2020 20.7 10.1 10.6 2021 18.4 8.1 10.3 2022 15.2 5.2 10.0 2023 12.4 2.8 9.6 After 2023 95.0 3.1 91.8 Total operating lease payments $ 185.9 $ 43.3 $ 142.5

ORGANIZATION AND BASIS OF PRE_4

ORGANIZATION AND BASIS OF PRESENTATION - Organization (Details) shares in Millions, customer in Millions	Jun. 04, 2018shares	Mar. 31, 2019subsidiarycustomersegmentMW
Summary Of Accounting Policies [Line Items]
Number of segments | segment		1
Owned generating capacity and renewable purchased power | MW		14,500
Number of customers served | customer		1.6
Kansas Gas And Electric Company | Westar Energy
Summary Of Accounting Policies [Line Items]
Number of active wholly owned subsidiaries | subsidiary		1
Transource Energy, LLC | GPE Transmission Holding Company, LLC
Summary Of Accounting Policies [Line Items]
Ownership percentage		13.50%
Transource Energy, LLC | AEP Transmission Holding Company, LLC
Summary Of Accounting Policies [Line Items]
Ownership interest		86.50%
Prairie Wind Transmission, LLC | Westar Energy
Summary Of Accounting Policies [Line Items]
Ownership percentage		50.00%
Great Plains Energy
Summary Of Accounting Policies [Line Items]
Conversion ratio	0.5981
Number of shares issued (in shares) | shares	128.9
Westar Energy
Summary Of Accounting Policies [Line Items]
Conversion ratio	1

ORGANIZATION AND BASIS OF PRE_5

ORGANIZATION AND BASIS OF PRESENTATION - Summary of Reclassifications (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Adjustments to reconcile income to net cash from operating activities:
Amortization of deferred refueling outage	$ 6.5	$ 4
Deferred income taxes, net	(1)	9.6
Investment tax credit amortization	(1)	(0.6)
Net deferred income taxes and credits	(2)	3.8
Other	(1.3)	(1.4)
Changes in working capital items:
Fuel inventory and supplies	44.6	6.9
Prepaid expenses and other current assets	35.5	(0.1)
Other current liabilities	(74.7)	(11.8)
Changes in other assets	12.8	0.7
Changes in other liabilities	(2.8)	23.7
Cash Flows from Operating Activities	362.1	259.6
CASH FLOWS FROM (USED IN) INVESTING ACTIVITIES:
Additions to property, plant and equipment	(309)	(174.8)
Other investing activities	1.3	(1.6)
Cash Flows used in Investing Activities	(271.4)	(174.1)
KCP&L
Adjustments to reconcile income to net cash from operating activities:
Amortization of deferred refueling outage	3.2	3.9
Deferred income taxes, net	(4.8)	5.6
Investment tax credit amortization	(0.2)	(0.3)
Net deferred income taxes and credits	(5)	5.3
Other	0.6	0.2
Changes in working capital items:
Fuel inventory and supplies	18.3	(2.8)
Prepaid expenses and other current assets	19.2	(2.5)
Other current liabilities	(31.9)	(1.8)
Changes in other assets	8.9	16.5
Changes in other liabilities	9.2	13.5
Cash Flows from Operating Activities	142.3	105
CASH FLOWS FROM (USED IN) INVESTING ACTIVITIES:
Additions to property, plant and equipment	(114.7)	(100.6)
Other investing activities	1.9	0.6
Cash Flows used in Investing Activities	$ (114.9)	(100.8)
KCP&L | As Previously Filed
Adjustments to reconcile income to net cash from operating activities:
Amortization of other		6.6
Amortization of deferred refueling outage		0
Deferred income taxes, net		5.6
Investment tax credit amortization		(0.3)
Net deferred income taxes and credits		0
Other		3.8
Changes in working capital items:
Fuel inventory and supplies		0
Fuel inventories		(1)
Materials and supplies		(1.8)
Prepaid expenses and other current assets		0
Accrued interest		8.3
Other current liabilities		0
Changes in other assets		0
Changes in other liabilities		0
Deferred refueling outage costs		0.9
Pension and post-retirement benefit obligations		9
Fuel recovery mechanisms		1.2
Cash Flows from Operating Activities		32.3
CASH FLOWS FROM (USED IN) INVESTING ACTIVITIES:
Additions to property, plant and equipment		0
Utility capital expenditures		(93.5)
Allowance for borrowed funds used during construction		(2)
Other investing activities		(4.5)
Cash Flows used in Investing Activities		(100)
KCP&L | As Recast
Adjustments to reconcile income to net cash from operating activities:
Amortization of other		0
Amortization of deferred refueling outage		3.9
Deferred income taxes, net		0
Investment tax credit amortization		0
Net deferred income taxes and credits		5.3
Other		0.2
Changes in working capital items:
Fuel inventory and supplies		(2.8)
Fuel inventories		0
Materials and supplies		0
Prepaid expenses and other current assets		(2.5)
Accrued interest		0
Other current liabilities		(1.8)
Changes in other assets		16.5
Changes in other liabilities		13.5
Deferred refueling outage costs		0
Pension and post-retirement benefit obligations		0
Fuel recovery mechanisms		0
Cash Flows from Operating Activities		32.3
CASH FLOWS FROM (USED IN) INVESTING ACTIVITIES:
Additions to property, plant and equipment		(100.6)
Utility capital expenditures		0
Allowance for borrowed funds used during construction		0
Other investing activities		0.6
Cash Flows used in Investing Activities		$ (100)

ORGANIZATION AND BASIS OF PRE_6

ORGANIZATION AND BASIS OF PRESENTATION - Restricted Cash (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018	Mar. 31, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Restricted cash	$ 414.3	$ 0	$ 0.1	$ 0.1
KCP&L
Debt Instrument [Line Items]
Restricted cash	414.3	$ 0	$ 0	$ 0
KCP&L | Senior Notes Due 2049 KCPL | Senior Notest
Debt Instrument [Line Items]
Long-term debt gross	$ 400
Interest rates (in hundredths)	4.125%
KCP&L | Senior Notes Due 2019 KCPL | Senior Notest
Debt Instrument [Line Items]
Interest rates (in hundredths)	7.15%

ORGANIZATION AND BASIS OF PRE_7

ORGANIZATION AND BASIS OF PRESENTATION - Fuel Inventory and Supplies (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Inventory [Line Items]
Fuel inventory	$ 132.2	$ 168.9
Supplies	334.3	342.1
Fuel inventory and supplies	466.5	511
Westar Energy
Inventory [Line Items]
Fuel inventory	74.2	87.8
Supplies	180.8	189
Fuel inventory and supplies	255	276.8
KCP&L
Inventory [Line Items]
Fuel inventory	39.2	57.8
Supplies	120.1	119.8
Fuel inventory and supplies	$ 159.3	$ 177.6

ORGANIZATION AND BASIS OF PRE_8

ORGANIZATION AND BASIS OF PRESENTATION - Summary of Property, Plant and Equipment (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Property, Plant and Equipment [Line Items]
Property, plant and equipment, net	$ 18,838.1	$ 18,782.5
Electric plant in service
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	27,161.1	26,916.7
Property, plant and equipment, adjustment	740.6	740.6
Accumulated depreciation	(9,856.2)	(9,694.1)
Property, plant and equipment, net	18,045.5	17,963.2
Construction work in progress
Property, Plant and Equipment [Line Items]
Property, plant and equipment, net	635.7	685.2
Nuclear fuel, net
Property, Plant and Equipment [Line Items]
Property, plant and equipment, net	155.9	133.1
Plant to be retired, net
Property, Plant and Equipment [Line Items]
Property, plant and equipment, net	1	1
Westar Energy
Property, Plant and Equipment [Line Items]
Property, plant and equipment, net	9,726.4	9,718.3
Westar Energy | Electric plant in service
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	13,263.5	13,176.7
Property, plant and equipment, adjustment	740.6	740.6
Accumulated depreciation	(4,721.2)	(4,642.8)
Property, plant and equipment, net	9,282.9	9,274.5
Westar Energy | Construction work in progress
Property, Plant and Equipment [Line Items]
Property, plant and equipment, net	365	376.7
Westar Energy | Nuclear fuel, net
Property, Plant and Equipment [Line Items]
Property, plant and equipment, net	77.5	66.1
Westar Energy | Plant to be retired, net
Property, Plant and Equipment [Line Items]
Property, plant and equipment, net	1	1
KCP&L
Property, Plant and Equipment [Line Items]
Property, plant and equipment, net	6,714.1	6,688.1
KCP&L | Electric plant in service
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	10,546	10,439.1
Property, plant and equipment, adjustment	0	0
Accumulated depreciation	(4,083.5)	(4,022.4)
Property, plant and equipment, net	6,462.5	6,416.7
KCP&L | Construction work in progress
Property, Plant and Equipment [Line Items]
Property, plant and equipment, net	173.2	204.4
KCP&L | Nuclear fuel, net
Property, Plant and Equipment [Line Items]
Property, plant and equipment, net	78.4	67
KCP&L | Plant to be retired, net
Property, Plant and Equipment [Line Items]
Property, plant and equipment, net	$ 0	$ 0

ORGANIZATION AND BASIS OF PRE_9

ORGANIZATION AND BASIS OF PRESENTATION - Other Income And Expense (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Entity Information [Line Items]
Non-service cost component of net benefit cost	$ (13.1)	$ (5.7)
Other	(6.3)	(4.9)
Other expense	(19.4)	(10.6)
Westar Energy
Entity Information [Line Items]
Non-service cost component of net benefit cost	(4.4)	(5.7)
Other	(6.2)	(4.9)
Other expense	(10.6)	(10.6)
KCP&L
Entity Information [Line Items]
Non-service cost component of net benefit cost	(5.1)	(6.7)
Other	0.1	(1.2)
Other expense	$ (5)	$ (7.9)

ORGANIZATION AND BASIS OF PR_10

ORGANIZATION AND BASIS OF PRESENTATION - Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Income
Net income	$ 103.4	$ 62.9
Less: Net income attributable to noncontrolling interests	3.9	2.4
Net income attributable to Evergy, Inc.	$ 99.5	$ 60.5
Common Shares Outstanding
Weighted average equivalent common shares outstanding - basic (in shares)	252.8	142.6
Add: effect of dilutive securities (in shares)	0.2	0.1
Diluted average number of common shares outstanding (in shares)	253	142.7
Basic and Diluted EPS (in dollars per share)	$ 0.39	$ 0.42

ORGANIZATION AND BASIS OF PR_11

ORGANIZATION AND BASIS OF PRESENTATION - Antidilutive Securities (Details) - shares	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Performance Shares
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share, amount	0	0

ORGANIZATION AND BASIS OF PR_12

ORGANIZATION AND BASIS OF PRESENTATION - Dividends Declared (Details) - USD ($) $ / shares in Units, $ in Millions	May 08, 2019	Mar. 31, 2019	Mar. 31, 2018
Dividends Payable [Line Items]
Dividends declared on common stock (in dollars per share)		$ 0.475	$ 0.4
Subsequent Event | KCP&L
Dividends Payable [Line Items]
Dividends payable	$ 65
Common stock | Subsequent Event
Dividends Payable [Line Items]
Dividends declared on common stock (in dollars per share)	$ 0.475

ORGANIZATION AND BASIS OF PR_13

ORGANIZATION AND BASIS OF PRESENTATION - Supplemental Cash Flow Information (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Cash paid for (received from):
Interest, net of amounts capitalized	$ 59.3	$ 33
Income taxes, net of refunds	(0.1)	(0.2)
Non-cash investing transactions:
Property, plant and equipment additions	47.1	29.8
Non-cash financing transactions:
Issuance of stock for compensation and reinvested dividends	0.5	0.1
Variable Interest Entities
Cash paid for (received from):
Interest, net of amounts capitalized	1	1.3
Westar Energy
Cash paid for (received from):
Interest, net of amounts capitalized	32.6	33
Income taxes, net of refunds	0	(0.2)
Non-cash investing transactions:
Property, plant and equipment additions	27.1	29.8
Non-cash financing transactions:
Issuance of stock for compensation and reinvested dividends	0	0.1
Westar Energy | Variable Interest Entities
Cash paid for (received from):
Interest, net of amounts capitalized	1	1.3
KCP&L
Cash paid for (received from):
Interest, net of amounts capitalized	19.6	22.7
Non-cash investing transactions:
Property, plant and equipment additions	$ 15.9	$ 20.9

ORGANIZATION AND BASIS OF PR_14

ORGANIZATION AND BASIS OF PRESENTATION - New Accounting Pronouncements (Details) - ASU 2016-02 $ in Millions	Jan. 01, 2019USD ($)
Entity Information [Line Items]
Lease asset	$ 110
Lease liability	110
Westar Energy
Entity Information [Line Items]
Lease asset	40
Lease liability	40
KCP&L
Entity Information [Line Items]
Lease asset	80
Lease liability	$ 80

ORGANIZATION AND BASIS OF PR_15

ORGANIZATION AND BASIS OF PRESENTATION - Pro Forma Financial Information (Details) $ / shares in Units, $ in Millions	3 Months Ended
	Mar. 31, 2018USD ($)$ / shares
Great Plains Energy
Business Acquisition [Line Items]
Operating revenues	$ 1,184.1
Net income attributable to Evergy, Inc.	$ 91.9
Basic earnings per common share (in dollars per share) | $ / shares	$ 0.34
Diluted earnings per common share (in dollars per share) | $ / shares	$ 0.34
Acquisition-related Costs
Business Acquisition [Line Items]
Merger-related, after tax costs	$ 5.2

REVENUE (Details)

REVENUE (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Disaggregation of Revenue [Line Items]
Total revenue from contracts with customers	$ 1,185.1	$ 601.3
Other	31.8	(1.1)
Revenues	1,216.9	600.2
Westar Energy
Disaggregation of Revenue [Line Items]
Total revenue from contracts with customers	592.3	601.3
Other	4.5	(1.1)
Revenues	596.8	600.2
KCP&L
Disaggregation of Revenue [Line Items]
Total revenue from contracts with customers	402.9	378
Other	22.5	19.1
Revenues	425.4	397.1
Residential
Disaggregation of Revenue [Line Items]
Total revenue from contracts with customers	451.7	180.3
Residential | Westar Energy
Disaggregation of Revenue [Line Items]
Total revenue from contracts with customers	192.3	180.3
Residential | KCP&L
Disaggregation of Revenue [Line Items]
Total revenue from contracts with customers	164.2	154.9
Commercial
Disaggregation of Revenue [Line Items]
Total revenue from contracts with customers	413.5	155.4
Commercial | Westar Energy
Disaggregation of Revenue [Line Items]
Total revenue from contracts with customers	164.3	155.4
Commercial | KCP&L
Disaggregation of Revenue [Line Items]
Total revenue from contracts with customers	183.8	181.8
Industrial
Disaggregation of Revenue [Line Items]
Total revenue from contracts with customers	147	93.5
Industrial | Westar Energy
Disaggregation of Revenue [Line Items]
Total revenue from contracts with customers	98.4	93.5
Industrial | KCP&L
Disaggregation of Revenue [Line Items]
Total revenue from contracts with customers	29.7	32.2
Other retail
Disaggregation of Revenue [Line Items]
Total revenue from contracts with customers	9.8	4.2
Other retail | Westar Energy
Disaggregation of Revenue [Line Items]
Total revenue from contracts with customers	5.1	4.2
Other retail | KCP&L
Disaggregation of Revenue [Line Items]
Total revenue from contracts with customers	2.6	2.7
Total electric retail
Disaggregation of Revenue [Line Items]
Total revenue from contracts with customers	1,022	433.4
Total electric retail | Westar Energy
Disaggregation of Revenue [Line Items]
Total revenue from contracts with customers	460.1	433.4
Total electric retail | KCP&L
Disaggregation of Revenue [Line Items]
Total revenue from contracts with customers	380.3	371.6
Wholesale
Disaggregation of Revenue [Line Items]
Total revenue from contracts with customers	83.1	94.2
Wholesale | Westar Energy
Disaggregation of Revenue [Line Items]
Total revenue from contracts with customers	61.3	94.2
Wholesale | KCP&L
Disaggregation of Revenue [Line Items]
Total revenue from contracts with customers	18.1	3.1
Transmission
Disaggregation of Revenue [Line Items]
Total revenue from contracts with customers	76.7	71.9
Transmission | Westar Energy
Disaggregation of Revenue [Line Items]
Total revenue from contracts with customers	69.2	71.9
Transmission | KCP&L
Disaggregation of Revenue [Line Items]
Total revenue from contracts with customers	3.1	3.3
Industrial steam and other
Disaggregation of Revenue [Line Items]
Total revenue from contracts with customers	3.3	1.8
Industrial steam and other | Westar Energy
Disaggregation of Revenue [Line Items]
Total revenue from contracts with customers	1.7	1.8
Industrial steam and other | KCP&L
Disaggregation of Revenue [Line Items]
Total revenue from contracts with customers	$ 1.4	$ 0

RECEIVABLES (Details)

RECEIVABLES (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Accounts, Notes, Loans and Financing Receivable [Line Items]
Other receivables	$ 77.5	$ 95
Allowance for doubtful accounts	(9.8)	(9.2)
Total	164.8	193.7
Westar Energy
Accounts, Notes, Loans and Financing Receivable [Line Items]
Other receivables	61.2	71.6
Allowance for doubtful accounts	(4.2)	(3.9)
Total	90.4	84.3
KCP&L
Accounts, Notes, Loans and Financing Receivable [Line Items]
Other receivables	11.9	15.8
Allowance for doubtful accounts	(4)	(3.8)
Total	41.8	62.7
Customer accounts receivable | Billed
Accounts, Notes, Loans and Financing Receivable [Line Items]
Customer accounts receivable	15	16.7
Customer accounts receivable | Billed | Westar Energy
Accounts, Notes, Loans and Financing Receivable [Line Items]
Customer accounts receivable	0	0
Customer accounts receivable | Billed | KCP&L
Accounts, Notes, Loans and Financing Receivable [Line Items]
Customer accounts receivable	8	7.8
Customer accounts receivable | Unbilled
Accounts, Notes, Loans and Financing Receivable [Line Items]
Customer accounts receivable	82.1	91.2
Customer accounts receivable | Unbilled | Westar Energy
Accounts, Notes, Loans and Financing Receivable [Line Items]
Customer accounts receivable	33.4	16.6
Customer accounts receivable | Unbilled | KCP&L
Accounts, Notes, Loans and Financing Receivable [Line Items]
Customer accounts receivable	$ 25.9	$ 42.9

RECEIVABLES - Narrative (Detail

RECEIVABLES - Narrative (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Entity Information [Line Items]
Other receivables, contracts with customers	$ 39.6	$ 65.8
Sale Of Accounts Receivable - KCPL and GMO
Accounts receivable pledged as collateral	359	365
Collateralized note payable	359	365
Westar Energy
Entity Information [Line Items]
Other receivables, contracts with customers	36.8	55.9
Sale Of Accounts Receivable - KCPL and GMO
Accounts receivable pledged as collateral	185	185
Collateralized note payable	185	185
Maximum amount of outstanding principal under receivables agreement from mid-Dec to mid-Jan	185
Maximum amount of outstanding principal under receivables agreement from mid-Jan to mid Feb	125
Maximum amount of outstanding principal under receivables agreement from mid February to mid July	185
Maximum amount of outstanding principal under receivable agreement from mid-July to expiration	200
KCP&L
Entity Information [Line Items]
Other receivables, contracts with customers	1	5.5
Sale Of Accounts Receivable - KCPL and GMO
Accounts receivable pledged as collateral	124	130
Collateralized note payable	124	$ 130
Maximum amount of outstanding principal under receivables agreement	130
GMO
Sale Of Accounts Receivable - KCPL and GMO
Maximum amount of outstanding principal under receivables agreement from mid-November to mid-June	50
Maximum amount of outstanding principal under receivables agreement from mid-June to expiration	$ 65

RECEIVABLES - Summary of Bad De

RECEIVABLES - Summary of Bad Debt Expense (Details) - SEC Schedule, 12-09, Allowance, Credit Loss - Customer Contracts - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Accounts, Notes, Loans and Financing Receivable [Line Items]
Impairment losses recognized on receivables	$ 4	$ 4
Westar Energy
Accounts, Notes, Loans and Financing Receivable [Line Items]
Impairment losses recognized on receivables	(0.3)	4
KCP&L
Accounts, Notes, Loans and Financing Receivable [Line Items]
Impairment losses recognized on receivables	$ 2.8	$ 1.7

RATE MATTERS AND REGULATION - P

RATE MATTERS AND REGULATION - Proceedings (Details) $ in Millions	1 Months Ended			3 Months Ended
	May 31, 2019USD ($)	Apr. 30, 2019USD ($)	Jan. 31, 2019USD ($)	Mar. 31, 2019
2018 Rate Case Proceedings | Westar Energy | Kansas Corporation Commission
Regulatory Proceedings [Line Items]
Refund percent on earnings over approved return on equity				0.5
Approved return on equity, percentage				9.30%
FERC 2019 TFR Proceeding | Westar Energy | Federal Energy Regulatory Commission
Regulatory Proceedings [Line Items]
Annual transmissions revenue estimated amount of increase (decrease) over prior year			$ (11.2)
FERC 2019 TFR Proceeding | KCP&L | Federal Energy Regulatory Commission
Regulatory Proceedings [Line Items]
Annual transmissions revenue estimated amount of increase (decrease) over prior year			$ (2.8)
Subsequent Event | Transmission Delivery Charge | Westar Energy | Kansas Corporation Commission
Regulatory Proceedings [Line Items]
Annual revenue decrease approved		$ 7.7
Scenario, Forecast | Subsequent Event | Transmission Delivery Charge | Westar Energy | Kansas Corporation Commission
Regulatory Proceedings [Line Items]
Annual transmissions revenue estimated amount of increase (decrease) over prior year	$ (8.3)

PENSION PLANS AND POST-RETIRE_3

PENSION PLANS AND POST-RETIREMENT BENEFITS (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Pension Benefits
Components of net periodic benefit costs [Abstract]
Service cost	$ 19.1	$ 8
Interest cost	27.5	12.7
Expected return on plan assets	(27.1)	(14)
Prior service cost	0.5	0.2
Recognized net actuarial (gain)/loss	6.9	8.2
Net periodic benefit costs before regulatory adjustment and intercompany allocations	26.9	15.1
Regulatory adjustment	(0.1)	2.8
Intercompany allocations	0	0
Net periodic benefit costs	26.8	17.9
Contributions by employer	12.3
Contributions by employer, remainder of fiscal year	103.2
Pension Benefits | Westar Energy
Components of net periodic benefit costs [Abstract]
Service cost	7.3	8
Interest cost	13.4	12.7
Expected return on plan assets	(13.7)	(14)
Prior service cost	0.4	0.2
Recognized net actuarial (gain)/loss	6.4	8.2
Net periodic benefit costs before regulatory adjustment and intercompany allocations	13.8	15.1
Regulatory adjustment	0.5	2.8
Intercompany allocations	0	0
Net periodic benefit costs	14.3	17.9
Contributions by employer	7.1
Contributions by employer, remainder of fiscal year	29.9
Pension Benefits | KCP&L
Components of net periodic benefit costs [Abstract]
Service cost	11.8	12.2
Interest cost	14.1	12.7
Expected return on plan assets	(12.3)	(13.9)
Prior service cost	0.2	0.2
Recognized net actuarial (gain)/loss	12.2	11.4
Net periodic benefit costs before regulatory adjustment and intercompany allocations	26	22.6
Regulatory adjustment	(0.6)	0.4
Intercompany allocations	(6.9)	(5.5)
Net periodic benefit costs	18.5	17.5
Contributions by employer	5.2
Contributions by employer, remainder of fiscal year	73.3
Post-Retirement Benefits
Components of net periodic benefit costs [Abstract]
Service cost	0.6	0.3
Interest cost	2.6	1.2
Expected return on plan assets	(2.4)	(1.7)
Prior service cost	0.1	0.1
Recognized net actuarial (gain)/loss	(0.3)	(0.1)
Net periodic benefit costs before regulatory adjustment and intercompany allocations	0.6	(0.2)
Regulatory adjustment	(0.7)	(0.4)
Intercompany allocations	0	0
Net periodic benefit costs	(0.1)	(0.6)
Contributions by employer	2.8
Post-Retirement Benefits | Westar Energy
Components of net periodic benefit costs [Abstract]
Service cost	0.3	0.3
Interest cost	1.4	1.2
Expected return on plan assets	(1.7)	(1.7)
Prior service cost	0.1	0.1
Recognized net actuarial (gain)/loss	(0.1)	(0.1)
Net periodic benefit costs before regulatory adjustment and intercompany allocations	0	(0.2)
Regulatory adjustment	(0.8)	(0.4)
Intercompany allocations	0	0
Net periodic benefit costs	(0.8)	(0.6)
Contributions by employer	0.7
Post-Retirement Benefits | KCP&L
Components of net periodic benefit costs [Abstract]
Service cost	0.3	0.5
Interest cost	1.2	1.2
Expected return on plan assets	(0.7)	(0.7)
Prior service cost	0	0
Recognized net actuarial (gain)/loss	(0.4)	0
Net periodic benefit costs before regulatory adjustment and intercompany allocations	0.4	1
Regulatory adjustment	0.1	(0.1)
Intercompany allocations	(0.1)	(0.3)
Net periodic benefit costs	0.4	$ 0.6
Contributions by employer	$ 2.1
Wolf Creek
Defined Benefit Plan Disclosure [Line Items]
Jointly owned utility plant, proportionate ownership share	94.00%
Wolf Creek | Westar Energy
Defined Benefit Plan Disclosure [Line Items]
Jointly owned utility plant, proportionate ownership share	47.00%
Wolf Creek | KCP&L
Defined Benefit Plan Disclosure [Line Items]
Jointly owned utility plant, proportionate ownership share	47.00%

SHORT-TERM BORROWINGS AND SHO_3

SHORT-TERM BORROWINGS AND SHORT-TERM BANK LINES OF CREDIT (Details)	1 Months Ended	3 Months Ended
	Mar. 31, 2019USD ($)loan	Mar. 31, 2019USD ($)	Dec. 31, 2018USD ($)
Short-term Debt [Line Items]
Available borrowings	$ 1,664,900,000	$ 1,664,900,000	$ 1,737,300,000
Cash Borrowings
Short-term Debt [Line Items]
Line of credit, maximum borrowing capacity	2,500,000,000	$ 2,500,000,000
Credit facility expiration date		Dec. 31, 2023
Debt instrument, debt default, threshold	$ 100,000,000	$ 100,000,000
Debt Instrument, debt to capitalization ratio (no more than)	65.00%	65.00%
Cash Borrowings | Maximum
Short-term Debt [Line Items]
Debt Instrument, debt to capitalization ratio (no more than)	65.00%	65.00%
Evergy, Inc.
Short-term Debt [Line Items]
Available borrowings	$ 349,000,000	$ 349,000,000	449,000,000
Westar Energy
Short-term Debt [Line Items]
Available borrowings	567,900,000	567,900,000	570,000,000
Westar Energy | Cash Borrowings
Short-term Debt [Line Items]
Debt instrument, debt default, threshold	$ 100,000,000	$ 100,000,000
Debt Instrument, debt to capitalization ratio (no more than)	65.00%	65.00%
Westar Energy | Cash Borrowings | Maximum
Short-term Debt [Line Items]
Debt Instrument, debt to capitalization ratio (no more than)	65.00%	65.00%
KCP&L
Short-term Debt [Line Items]
Available borrowings	$ 421,300,000	$ 421,300,000	420,400,000
KCP&L | Cash Borrowings
Short-term Debt [Line Items]
Debt instrument, debt default, threshold	$ 100,000,000	$ 100,000,000
Debt Instrument, debt to capitalization ratio (no more than)	65.00%	65.00%
KCP&L | Cash Borrowings | Maximum
Short-term Debt [Line Items]
Debt Instrument, debt to capitalization ratio (no more than)	65.00%	65.00%
GMO
Short-term Debt [Line Items]
Available borrowings	$ 326,700,000	$ 326,700,000	$ 297,900,000
GMO | Cash Borrowings
Short-term Debt [Line Items]
Debt instrument, debt default, threshold	$ 100,000,000	$ 100,000,000
Debt Instrument, debt to capitalization ratio (no more than)	65.00%	65.00%
GMO | Cash Borrowings | Maximum
Short-term Debt [Line Items]
Debt Instrument, debt to capitalization ratio (no more than)	65.00%	65.00%
Term Loan | Line of Credit
Short-term Debt [Line Items]
Line of credit, maximum borrowing capacity	$ 1,000,000,000	$ 1,000,000,000
Debt instrument, term	6 months
Number of loans | loan	2
Proceeds from lines of credit		500,000,000
Available borrowings	$ 500,000,000	500,000,000
Long-term line of credit	$ 500,000,000	$ 500,000,000
Interest rate during period	3.03%	3.03%

SHORT-TERM BORROWINGS AND SHO_4

SHORT-TERM BORROWINGS AND SHORT-TERM BANK LINES OF CREDIT - Schedule of Short Term Debt (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Short-term Debt [Line Items]
Credit Facility	$ 2,500	$ 2,500
Available Borrowings	1,664.9	1,737.3
Evergy, Inc.
Short-term Debt [Line Items]
Credit Facility	450	450
Available Borrowings	$ 349	$ 449
Weighted Average Interest Rate on Short-Term Borrowings	3.73%	0.00%
Westar Energy
Short-term Debt [Line Items]
Credit Facility	$ 1,000	$ 1,000
Available Borrowings	$ 567.9	$ 570
Weighted Average Interest Rate on Short-Term Borrowings	2.77%	3.08%
KCP&L
Short-term Debt [Line Items]
Credit Facility	$ 600	$ 600
Available Borrowings	$ 421.3	$ 420.4
Weighted Average Interest Rate on Short-Term Borrowings	2.89%	2.95%
GMO
Short-term Debt [Line Items]
Credit Facility	$ 450	$ 450
Available Borrowings	$ 326.7	$ 297.9
Weighted Average Interest Rate on Short-Term Borrowings	2.75%	3.00%
Commercial Paper
Short-term Debt [Line Items]
Long-term line of credit	$ 711	$ 738.6
Commercial Paper | Westar Energy
Short-term Debt [Line Items]
Long-term line of credit	413.8	411.7
Commercial Paper | KCP&L
Short-term Debt [Line Items]
Long-term line of credit	176	176.9
Commercial Paper | GMO
Short-term Debt [Line Items]
Long-term line of credit	121.2	150
Letters of Credit
Short-term Debt [Line Items]
Letters of Credit	24.1	24.1
Letters of Credit | Evergy, Inc.
Short-term Debt [Line Items]
Letters of Credit	1	1
Letters of Credit | Westar Energy
Short-term Debt [Line Items]
Letters of Credit	18.3	18.3
Letters of Credit | KCP&L
Short-term Debt [Line Items]
Letters of Credit	2.7	2.7
Letters of Credit | GMO
Short-term Debt [Line Items]
Letters of Credit	2.1	2.1
Cash Borrowings
Short-term Debt [Line Items]
Long-term line of credit	100	0
Cash Borrowings | Evergy, Inc.
Short-term Debt [Line Items]
Long-term line of credit	100	0
Cash Borrowings | Westar Energy
Short-term Debt [Line Items]
Long-term line of credit	0	0
Cash Borrowings | KCP&L
Short-term Debt [Line Items]
Long-term line of credit	0	0
Cash Borrowings | GMO
Short-term Debt [Line Items]
Long-term line of credit	$ 0	$ 0

LONG-TERM DEBT (Details)

LONG-TERM DEBT (Details) $ in Millions	Mar. 31, 2019USD ($)
KCP&L | Unsecured Debt | Senior Notes due 2023 KCPL
Debt Instrument [Line Items]
Long-term debt gross	$ 300
Interest rates (in hundredths)	3.15%
KCP&L | Unsecured Debt | Senior Notes due 2025 KCPL
Debt Instrument [Line Items]
Long-term debt gross	$ 350
Interest rates (in hundredths)	3.65%
KCP&L | Unsecured Debt | Senior notes due 2035 KCPL
Debt Instrument [Line Items]
Long-term debt gross	$ 250
Interest rates (in hundredths)	6.05%
KCP&L | Unsecured Debt | Senior Notes Due 2041 KCPL
Debt Instrument [Line Items]
Long-term debt gross	$ 400
Interest rates (in hundredths)	5.30%
KCP&L | Unsecured Debt | Senior Notes Due 2047 KCPL
Debt Instrument [Line Items]
Long-term debt gross	$ 300
Interest rates (in hundredths)	4.20%
KCP&L | Unsecured Debt | Senior Notes Due 2048 KCPL
Debt Instrument [Line Items]
Long-term debt gross	$ 300
Interest rates (in hundredths)	4.20%
KCP&L | Senior Notest | Senior Notes Due 2049 KCPL
Debt Instrument [Line Items]
Long-term debt gross	$ 400
Interest rates (in hundredths)	4.125%
KCP&L | Senior Notest | Senior Notes Due 2019 KCPL
Debt Instrument [Line Items]
Interest rates (in hundredths)	7.15%
Repayments of long-term debt	$ 400
GMO | Senior Notest | Senior Notes Due 2022 GMO
Debt Instrument [Line Items]
Long-term debt gross	$ 100
Interest rates (in hundredths)	3.74%

FAIR VALUE MEASUREMENTS - Debt

FAIR VALUE MEASUREMENTS - Debt (Details) - USD ($)	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Notional contract amount			$ 500,000,000
Fair value adjustments	$ (19,200,000)		(5,400,000)
Loss on derivative hedging instruments	13,800,000	$ 0
Book Value | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt	7,827,000,000		7,341,700,000
Book Value | Fair Value, Measurements, Recurring | Variable Interest Entities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt	51,100,000		81,400,000
Fair Value | Fair Value, Measurements, Recurring | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt	8,130,500,000		7,412,100,000
Fair Value | Fair Value, Measurements, Recurring | Level 2 | Variable Interest Entities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt	50,900,000		81,300,000
Westar Energy | Book Value | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt	3,690,000,000		3,689,800,000
Westar Energy | Book Value | Fair Value, Measurements, Recurring | Variable Interest Entities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt	51,100,000		81,400,000
Westar Energy | Fair Value | Fair Value, Measurements, Recurring | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt	3,884,400,000		3,771,300,000
Westar Energy | Fair Value | Fair Value, Measurements, Recurring | Level 2 | Variable Interest Entities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt	50,900,000		81,300,000
KCP&L | Book Value | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt	2,924,600,000		2,530,100,000
KCP&L | Fair Value | Fair Value, Measurements, Recurring | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt	3,130,200,000		2,637,500,000
Long-Term debt fair value adjustment
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt gross	$ 136,800,000		$ 144,800,000

FAIR VALUE MEASUREMENTS - Recur

FAIR VALUE MEASUREMENTS - Recurring (Details) - Fair Value, Measurements, Recurring - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Assets
Total nuclear decommissioning trust	$ 518.3	$ 472.1
Total rabbi trust	44.6	43.8
Total self-insured health plan trust	12.6	12.4
Total Assets	575.5	528.3
Liabilities
Total	19.2	5.4
Interest rate swaps
Liabilities
Interest rate swaps	19.2	5.4
Level 1
Assets
Total nuclear decommissioning trust	443.8	396
Total rabbi trust	0.6	0.2
Total self-insured health plan trust	7.6	8.8
Total Assets	452	405
Liabilities
Total	0	0
Level 1 | Interest rate swaps
Liabilities
Interest rate swaps	0	0
Level 2
Assets
Total nuclear decommissioning trust	32.7	33.5
Total rabbi trust	0	0
Total self-insured health plan trust	5	3.6
Total Assets	37.7	37.1
Liabilities
Total	19.2	5.4
Level 2 | Interest rate swaps
Liabilities
Interest rate swaps	19.2	5.4
Level 3
Assets
Total nuclear decommissioning trust	0	0
Total rabbi trust	0	0
Total self-insured health plan trust	0	0
Total Assets	0	0
Liabilities
Total	0	0
Level 3 | Interest rate swaps
Liabilities
Interest rate swaps	0	0
NAV
Assets
Total nuclear decommissioning trust	41.8	42.6
Total rabbi trust	44	43.6
Total self-insured health plan trust	0	0
Total Assets	85.8	86.2
Liabilities
Total	0	0
NAV | Interest rate swaps
Liabilities
Interest rate swaps	0	0
Westar Energy
Assets
Total nuclear decommissioning trust	248.4	227.5
Total rabbi trust	31.1	30.6
Total Assets	279.5	258.1
Westar Energy | Core bond fund
Assets
Total nuclear decommissioning trust	34.6	37.5
Total rabbi trust	24.7	24.8
Westar Energy | High-yield bond fund
Assets
Total nuclear decommissioning trust	20.6	18.9
Westar Energy | Emerging markets bond fund
Assets
Total nuclear decommissioning trust	16.4	15.4
Westar Energy | Combination debt/equity/other fund
Assets
Total nuclear decommissioning trust	14.7	12.9
Total rabbi trust	6.2	5.6
Westar Energy | Alternative investments fund
Assets
Total nuclear decommissioning trust	23.3	24.1
Westar Energy | Real estate securities fund
Assets
Total nuclear decommissioning trust	12	11.8
Westar Energy | Cash equivalents
Assets
Total nuclear decommissioning trust	0.2	0.1
Total rabbi trust	0.2	0.2
Westar Energy | Level 1
Assets
Total nuclear decommissioning trust	206.6	184.9
Total rabbi trust	0.2	0.2
Total Assets	206.8	185.1
Westar Energy | Level 1 | Core bond fund
Assets
Total nuclear decommissioning trust	34.6	37.5
Total rabbi trust	0	0
Westar Energy | Level 1 | High-yield bond fund
Assets
Total nuclear decommissioning trust	20.6	18.9
Westar Energy | Level 1 | Emerging markets bond fund
Assets
Total nuclear decommissioning trust	16.4	15.4
Westar Energy | Level 1 | Combination debt/equity/other fund
Assets
Total nuclear decommissioning trust	14.7	12.9
Total rabbi trust	0	0
Westar Energy | Level 1 | Alternative investments fund
Assets
Total nuclear decommissioning trust	0	0
Westar Energy | Level 1 | Real estate securities fund
Assets
Total nuclear decommissioning trust	0	0
Westar Energy | Level 1 | Cash equivalents
Assets
Total nuclear decommissioning trust	0.2	0.1
Total rabbi trust	0.2	0.2
Westar Energy | Level 2
Assets
Total nuclear decommissioning trust	0	0
Total rabbi trust	0	0
Total Assets	0	0
Westar Energy | Level 2 | Core bond fund
Assets
Total nuclear decommissioning trust	0	0
Total rabbi trust	0	0
Westar Energy | Level 2 | High-yield bond fund
Assets
Total nuclear decommissioning trust	0	0
Westar Energy | Level 2 | Emerging markets bond fund
Assets
Total nuclear decommissioning trust	0	0
Westar Energy | Level 2 | Combination debt/equity/other fund
Assets
Total nuclear decommissioning trust	0	0
Total rabbi trust	0	0
Westar Energy | Level 2 | Alternative investments fund
Assets
Total nuclear decommissioning trust	0	0
Westar Energy | Level 2 | Real estate securities fund
Assets
Total nuclear decommissioning trust	0	0
Westar Energy | Level 2 | Cash equivalents
Assets
Total nuclear decommissioning trust	0	0
Total rabbi trust	0	0
Westar Energy | Level 3
Assets
Total nuclear decommissioning trust	0	0
Total rabbi trust	0	0
Total Assets	0	0
Westar Energy | Level 3 | Core bond fund
Assets
Total nuclear decommissioning trust	0	0
Total rabbi trust	0	0
Westar Energy | Level 3 | High-yield bond fund
Assets
Total nuclear decommissioning trust	0	0
Westar Energy | Level 3 | Emerging markets bond fund
Assets
Total nuclear decommissioning trust	0	0
Westar Energy | Level 3 | Combination debt/equity/other fund
Assets
Total nuclear decommissioning trust	0	0
Total rabbi trust	0	0
Westar Energy | Level 3 | Alternative investments fund
Assets
Total nuclear decommissioning trust	0	0
Westar Energy | Level 3 | Real estate securities fund
Assets
Total nuclear decommissioning trust	0	0
Westar Energy | Level 3 | Cash equivalents
Assets
Total nuclear decommissioning trust	0	0
Total rabbi trust	0	0
Westar Energy | NAV
Assets
Total nuclear decommissioning trust	41.8	42.6
Total rabbi trust	30.9	30.4
Total Assets	72.7	73
Westar Energy | NAV | Core bond fund
Assets
Total nuclear decommissioning trust	0	0
Total rabbi trust	24.7	24.8
Westar Energy | NAV | High-yield bond fund
Assets
Total nuclear decommissioning trust	0	0
Westar Energy | NAV | Emerging markets bond fund
Assets
Total nuclear decommissioning trust	0	0
Westar Energy | NAV | Combination debt/equity/other fund
Assets
Total nuclear decommissioning trust	0	0
Total rabbi trust	6.2	5.6
Westar Energy | NAV | Alternative investments fund
Assets
Total nuclear decommissioning trust	23.3	24.1
Westar Energy | NAV | Real estate securities fund
Assets
Total nuclear decommissioning trust	12	11.8
Westar Energy | NAV | Cash equivalents
Assets
Total nuclear decommissioning trust	0	0
Total rabbi trust	0	0
Westar Energy | Domestic | Equity securities
Assets
Total nuclear decommissioning trust	80.1	70.6
Westar Energy | Domestic | Level 1 | Equity securities
Assets
Total nuclear decommissioning trust	73.6	63.9
Westar Energy | Domestic | Level 2 | Equity securities
Assets
Total nuclear decommissioning trust	0	0
Westar Energy | Domestic | Level 3 | Equity securities
Assets
Total nuclear decommissioning trust	0	0
Westar Energy | Domestic | NAV | Equity securities
Assets
Total nuclear decommissioning trust	6.5	6.7
Westar Energy | International | Equity securities
Assets
Total nuclear decommissioning trust	46.5	36.2
Westar Energy | International | Level 1 | Equity securities
Assets
Total nuclear decommissioning trust	46.5	36.2
Westar Energy | International | Level 2 | Equity securities
Assets
Total nuclear decommissioning trust	0	0
Westar Energy | International | Level 3 | Equity securities
Assets
Total nuclear decommissioning trust	0	0
Westar Energy | International | NAV | Equity securities
Assets
Total nuclear decommissioning trust	0	0
KCP&L
Assets
Total nuclear decommissioning trust	269.9	244.6
Total self-insured health plan trust	12.6	12.4
Total Assets	282.5	257
KCP&L | Equity securities
Assets
Total nuclear decommissioning trust	188.3	166.6
Total self-insured health plan trust	0.5	0.5
KCP&L | Cash equivalents
Assets
Total nuclear decommissioning trust	2.9	1.7
KCP&L | U.S. Treasury
Assets
Total nuclear decommissioning trust	46	42.1
KCP&L | U.S. Agency
Assets
Total nuclear decommissioning trust	0.4	0.4
KCP&L | State and local obligations
Assets
Total nuclear decommissioning trust	2.1	2.1
KCP&L | Corporate bonds
Assets
Total nuclear decommissioning trust	30.6	30.9
KCP&L | Foreign governments
Assets
Total nuclear decommissioning trust	0.1	0.1
KCP&L | Other
Assets
Total nuclear decommissioning trust	(0.5)	0.7
KCP&L | Debt securities
Assets
Total self-insured health plan trust	4.3	3.9
KCP&L | Cash and cash equivalents
Assets
Total self-insured health plan trust	6.7	8
KCP&L | Other
Assets
Total self-insured health plan trust	1.1
KCP&L | Level 1
Assets
Total nuclear decommissioning trust	237.2	211.1
Total self-insured health plan trust	7.6	8.8
Total Assets	244.8	219.9
KCP&L | Level 1 | Equity securities
Assets
Total nuclear decommissioning trust	188.3	166.6
Total self-insured health plan trust	0.5	0.5
KCP&L | Level 1 | Cash equivalents
Assets
Total nuclear decommissioning trust	2.9	1.7
KCP&L | Level 1 | U.S. Treasury
Assets
Total nuclear decommissioning trust	46	42.1
KCP&L | Level 1 | U.S. Agency
Assets
Total nuclear decommissioning trust	0	0
KCP&L | Level 1 | State and local obligations
Assets
Total nuclear decommissioning trust	0	0
KCP&L | Level 1 | Corporate bonds
Assets
Total nuclear decommissioning trust	0	0
KCP&L | Level 1 | Foreign governments
Assets
Total nuclear decommissioning trust	0	0
KCP&L | Level 1 | Other
Assets
Total nuclear decommissioning trust	0	0.7
KCP&L | Level 1 | Debt securities
Assets
Total self-insured health plan trust	0.4	0.3
KCP&L | Level 1 | Cash and cash equivalents
Assets
Total self-insured health plan trust	6.7	8
KCP&L | Level 1 | Other
Assets
Total self-insured health plan trust	0
KCP&L | Level 2
Assets
Total nuclear decommissioning trust	32.7	33.5
Total self-insured health plan trust	5	3.6
Total Assets	37.7	37.1
KCP&L | Level 2 | Equity securities
Assets
Total nuclear decommissioning trust	0	0
Total self-insured health plan trust	0	0
KCP&L | Level 2 | Cash equivalents
Assets
Total nuclear decommissioning trust	0	0
KCP&L | Level 2 | U.S. Treasury
Assets
Total nuclear decommissioning trust	0	0
KCP&L | Level 2 | U.S. Agency
Assets
Total nuclear decommissioning trust	0.4	0.4
KCP&L | Level 2 | State and local obligations
Assets
Total nuclear decommissioning trust	2.1	2.1
KCP&L | Level 2 | Corporate bonds
Assets
Total nuclear decommissioning trust	30.6	30.9
KCP&L | Level 2 | Foreign governments
Assets
Total nuclear decommissioning trust	0.1	0.1
KCP&L | Level 2 | Other
Assets
Total nuclear decommissioning trust	(0.5)	0
KCP&L | Level 2 | Debt securities
Assets
Total self-insured health plan trust	3.9	3.6
KCP&L | Level 2 | Cash and cash equivalents
Assets
Total self-insured health plan trust	0	0
KCP&L | Level 2 | Other
Assets
Total self-insured health plan trust	1.1
KCP&L | Level 3
Assets
Total nuclear decommissioning trust	0	0
Total self-insured health plan trust	0	0
Total Assets	0	0
KCP&L | Level 3 | Equity securities
Assets
Total nuclear decommissioning trust	0	0
Total self-insured health plan trust	0	0
KCP&L | Level 3 | Cash equivalents
Assets
Total nuclear decommissioning trust	0	0
KCP&L | Level 3 | U.S. Treasury
Assets
Total nuclear decommissioning trust	0	0
KCP&L | Level 3 | U.S. Agency
Assets
Total nuclear decommissioning trust	0	0
KCP&L | Level 3 | State and local obligations
Assets
Total nuclear decommissioning trust	0	0
KCP&L | Level 3 | Corporate bonds
Assets
Total nuclear decommissioning trust	0	0
KCP&L | Level 3 | Foreign governments
Assets
Total nuclear decommissioning trust	0	0
KCP&L | Level 3 | Other
Assets
Total nuclear decommissioning trust	0	0
KCP&L | Level 3 | Debt securities
Assets
Total self-insured health plan trust	0	0
KCP&L | Level 3 | Cash and cash equivalents
Assets
Total self-insured health plan trust	0	0
KCP&L | Level 3 | Other
Assets
Total self-insured health plan trust	0
KCP&L | NAV
Assets
Total nuclear decommissioning trust	0	0
Total self-insured health plan trust	0	0
Total Assets	0	0
KCP&L | NAV | Equity securities
Assets
Total nuclear decommissioning trust	0	0
Total self-insured health plan trust	0	0
KCP&L | NAV | Cash equivalents
Assets
Total nuclear decommissioning trust	0	0
KCP&L | NAV | U.S. Treasury
Assets
Total nuclear decommissioning trust	0	0
KCP&L | NAV | U.S. Agency
Assets
Total nuclear decommissioning trust	0	0
KCP&L | NAV | State and local obligations
Assets
Total nuclear decommissioning trust	0	0
KCP&L | NAV | Corporate bonds
Assets
Total nuclear decommissioning trust	0	0
KCP&L | NAV | Foreign governments
Assets
Total nuclear decommissioning trust	0	0
KCP&L | NAV | Other
Assets
Total nuclear decommissioning trust	0	0
KCP&L | NAV | Debt securities
Assets
Total self-insured health plan trust	0	0
KCP&L | NAV | Cash and cash equivalents
Assets
Total self-insured health plan trust	0	0
KCP&L | NAV | Other
Assets
Total self-insured health plan trust	0
Other Evergy
Assets
Total rabbi trust	13.5	13.2
Liabilities
Total	19.2	5.4
Other Evergy | Interest rate swaps
Liabilities
Interest rate swaps	19.2	5.4
Other Evergy | Cash and cash equivalents
Assets
Total rabbi trust	0.4
Other Evergy | Fixed income fund
Assets
Total rabbi trust	13.1	13.2
Other Evergy | Level 1
Assets
Total rabbi trust	0.4	0
Liabilities
Total	0	0
Other Evergy | Level 1 | Interest rate swaps
Liabilities
Interest rate swaps	0	0
Other Evergy | Level 1 | Cash and cash equivalents
Assets
Total rabbi trust	0.4
Other Evergy | Level 1 | Fixed income fund
Assets
Total rabbi trust	0	0
Other Evergy | Level 2
Assets
Total rabbi trust	0	0
Liabilities
Total	19.2	5.4
Other Evergy | Level 2 | Interest rate swaps
Liabilities
Interest rate swaps	19.2	5.4
Other Evergy | Level 2 | Cash and cash equivalents
Assets
Total rabbi trust	0
Other Evergy | Level 2 | Fixed income fund
Assets
Total rabbi trust	0	0
Other Evergy | Level 3
Assets
Total rabbi trust	0	0
Liabilities
Total	0	0
Other Evergy | Level 3 | Interest rate swaps
Liabilities
Interest rate swaps	0	0
Other Evergy | Level 3 | Cash and cash equivalents
Assets
Total rabbi trust	0
Other Evergy | Level 3 | Fixed income fund
Assets
Total rabbi trust	0	0
Other Evergy | NAV
Assets
Total rabbi trust	13.1	13.2
Liabilities
Total	0	0
Other Evergy | NAV | Interest rate swaps
Liabilities
Interest rate swaps	0	0
Other Evergy | NAV | Cash and cash equivalents
Assets
Total rabbi trust	0
Other Evergy | NAV | Fixed income fund
Assets
Total rabbi trust	$ 13.1	$ 13.2

FAIR VALUE MEASUREMENTS - NAV (

FAIR VALUE MEASUREMENTS - NAV (Details) $ in Millions	3 Months Ended
	Mar. 31, 2019USD ($)fundextension	Dec. 31, 2018USD ($)
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Unfunded Commitments	$ 4	$ 4.3
Westar Energy | Alternative investments fund
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Unfunded Commitments	$ 0	0
Length of Settlement	65 days
Westar Energy | Real estate securities fund
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Unfunded Commitments	$ 0	0
Length of Settlement	65 days
Westar Energy | Nuclear decommissioning trust:
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Total nuclear decommissioning trust	$ 41.8
Unfunded Commitments	4	4.3
Westar Energy | Core bond fund
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Unfunded Commitments	0	0
Westar Energy | Combination debt/equity/other fund
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Unfunded Commitments	0	0
Westar Energy | Rabbi trust:
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Unfunded Commitments	0	0
Other Evergy
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Unfunded Commitments	0	0
Domestic | Westar Energy | Equity securities
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Unfunded Commitments	$ 4	4.3
NAV, Number of funds | fund	5
NAV, Number of funds making distributions | fund	3
Domestic | Westar Energy | Equity Securities - Fourth Fund
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Length of Settlement	15 years
NAV, Extension term	1 year
NAV, Number of extensions | extension	3
Domestic | Westar Energy | Equity Securities - Fifth Fund
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Length of Settlement	15 years
Fair Value, Measurements, Recurring
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Total nuclear decommissioning trust	$ 518.3	472.1
Total rabbi trust	44.6	43.8
Total Assets	575.5	528.3
Fair Value, Measurements, Recurring | Westar Energy
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Total nuclear decommissioning trust	248.4	227.5
Total rabbi trust	31.1	30.6
Total Assets	279.5	258.1
Fair Value, Measurements, Recurring | Westar Energy | Alternative investments fund
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Total nuclear decommissioning trust	23.3	24.1
Fair Value, Measurements, Recurring | Westar Energy | Real estate securities fund
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Total nuclear decommissioning trust	12	11.8
Fair Value, Measurements, Recurring | Westar Energy | Core bond fund
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Total nuclear decommissioning trust	34.6	37.5
Total rabbi trust	24.7	24.8
Fair Value, Measurements, Recurring | Westar Energy | Combination debt/equity/other fund
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Total nuclear decommissioning trust	14.7	12.9
Total rabbi trust	6.2	5.6
Fair Value, Measurements, Recurring | Other Evergy
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Total rabbi trust	13.5	13.2
Fair Value, Measurements, Recurring | Domestic | Westar Energy | Equity securities
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Total nuclear decommissioning trust	80.1	70.6
NAV | Fair Value, Measurements, Recurring
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Total nuclear decommissioning trust	41.8	42.6
Total rabbi trust	44	43.6
Total Assets	85.8	86.2
NAV | Fair Value, Measurements, Recurring | Westar Energy
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Total nuclear decommissioning trust	41.8	42.6
Total rabbi trust	30.9	30.4
Total Assets	72.7	73
NAV | Fair Value, Measurements, Recurring | Westar Energy | Alternative investments fund
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Total nuclear decommissioning trust	23.3	24.1
NAV | Fair Value, Measurements, Recurring | Westar Energy | Real estate securities fund
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Total nuclear decommissioning trust	12	11.8
NAV | Fair Value, Measurements, Recurring | Westar Energy | Nuclear decommissioning trust:
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Total nuclear decommissioning trust		42.6
NAV | Fair Value, Measurements, Recurring | Westar Energy | Core bond fund
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Total nuclear decommissioning trust	0	0
Total rabbi trust	24.7	24.8
NAV | Fair Value, Measurements, Recurring | Westar Energy | Combination debt/equity/other fund
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Total nuclear decommissioning trust	0	0
Total rabbi trust	6.2	5.6
NAV | Fair Value, Measurements, Recurring | Westar Energy | Rabbi trust:
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Total rabbi trust	30.9	30.4
NAV | Fair Value, Measurements, Recurring | Other Evergy
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Total rabbi trust	13.1	13.2
NAV | Fair Value, Measurements, Recurring | Domestic | Westar Energy | Equity securities
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]
Total nuclear decommissioning trust	$ 6.5	$ 6.7

FAIR VALUE MEASUREMENTS - Gain

FAIR VALUE MEASUREMENTS - Gain (Loss) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Fair Value, Measured on Recurring Basis, Gain (Loss) Included in Earnings [Line Items]
Unrealized gain (losses)	$ 40.5	$ (12.2)
Nuclear decommissioning trust - equity securities
Fair Value, Measured on Recurring Basis, Gain (Loss) Included in Earnings [Line Items]
Unrealized gain (losses)	37.9	(11.7)
Rabbi trusts
Fair Value, Measured on Recurring Basis, Gain (Loss) Included in Earnings [Line Items]
Unrealized gain (losses)	0.5	(0.5)
Nuclear decommissioning trust - debt securities
Fair Value, Measured on Recurring Basis, Gain (Loss) Included in Earnings [Line Items]
Unrealized gain (losses)	2.1	0
Westar Energy
Fair Value, Measured on Recurring Basis, Gain (Loss) Included in Earnings [Line Items]
Unrealized gain (losses)	18.5	(12.2)
Westar Energy | Nuclear decommissioning trust - equity securities
Fair Value, Measured on Recurring Basis, Gain (Loss) Included in Earnings [Line Items]
Unrealized gain (losses)	17.2	(11.7)
Westar Energy | Rabbi trusts
Fair Value, Measured on Recurring Basis, Gain (Loss) Included in Earnings [Line Items]
Unrealized gain (losses)	1.3	(0.5)
KCP&L
Fair Value, Measured on Recurring Basis, Gain (Loss) Included in Earnings [Line Items]
Unrealized gain (losses)	22.8	(5.2)
KCP&L | Nuclear decommissioning trust - equity securities
Fair Value, Measured on Recurring Basis, Gain (Loss) Included in Earnings [Line Items]
Unrealized gain (losses)	20.7	(3.6)
KCP&L | Nuclear decommissioning trust - debt securities
Fair Value, Measured on Recurring Basis, Gain (Loss) Included in Earnings [Line Items]
Unrealized gain (losses)	$ 2.1	$ (1.6)

RELATED PARTY TRANSACTIONS AN_3

RELATED PARTY TRANSACTIONS AND RELATIONSHIPS (Details) - USD ($)	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Related Party Transaction [Line Items]
Less: current portion	$ 16,100,000
Total long-term obligations under operating leases	86,900,000
Westar Energy
Related Party Transaction [Line Items]
Less: current portion	10,500,000
Total long-term obligations under operating leases	24,300,000
Westar Energy | GMO
Related Party Transaction [Line Items]
Due from (to) related parties	2,500,000		$ 2,600,000
Westar Energy | KCP&L
Related Party Transaction [Line Items]
Due from (to) related parties	(8,300,000)		(13,500,000)
Westar Energy | KCP&L | Operating Expenses and Capital Costs Billed
Related Party Transaction [Line Items]
Related party transaction	7,400,000
Westar Energy | Evergy
Related Party Transaction [Line Items]
Due from (to) related parties	(500,000)		(1,400,000)
Westar Energy | Evergy | Income Tax Receivable
Related Party Transaction [Line Items]
Due from (to) related parties	32,000,000		42,700,000
KCP&L
Related Party Transaction [Line Items]
Less: current portion	6,300,000
Total long-term obligations under operating leases	93,000,000
KCP&L | Money Pool
Related Party Transaction [Line Items]
Due from (to) related parties	0		0
KCP&L | GMO
Related Party Transaction [Line Items]
Due from (to) related parties	53,600,000		72,600,000
KCP&L | Westar Energy
Related Party Transaction [Line Items]
Due from (to) related parties	8,300,000		13,500,000
KCP&L | Evergy
Related Party Transaction [Line Items]
Due from (to) related parties	19,300,000		15,700,000
KCP&L | Evergy | Income Taxes Payable
Related Party Transaction [Line Items]
Due from (to) related parties	$ (10,600,000)		$ (2,000,000)
Iatan No 1 And 2 | GMO
Related Party Transaction [Line Items]
Jointly owned utility plant, proportionate ownership share	18.00%
Iatan No 1 And 2 | KCP&L | GMO | Operating Expenses and Capital Costs Billed
Related Party Transaction [Line Items]
Related party transaction	$ 42,000,000	$ 46,400,000
Jeffrey Energy Center | GMO
Related Party Transaction [Line Items]
Jointly owned utility plant, proportionate ownership share	8.00%
Jeffrey Energy Center | Westar Energy | GMO | Operating Expenses and Capital Costs Billed
Related Party Transaction [Line Items]
Related party transaction	$ 6,300,000
La Cygne Station | Westar Energy
Related Party Transaction [Line Items]
Jointly owned utility plant, proportionate ownership share	50.00%
La Cygne Station | KCP&L | Westar Energy | Operating Expenses and Capital Costs Billed
Related Party Transaction [Line Items]
Related party transaction	$ 31,500,000
Westar Energy | KCP&L | Subsidiary of Common Parent
Related Party Transaction [Line Items]
Operating lease, right-of-use asset	30,000,000
Less: current portion	600,000
Total long-term obligations under operating leases	$ 29,400,000

SHAREHOLDERS' EQUITY (Details)

SHAREHOLDERS' EQUITY (Details) - USD ($)	3 Months Ended	9 Months Ended
	Mar. 31, 2019	Mar. 31, 2019	Feb. 28, 2019	Dec. 31, 2018	Nov. 30, 2018	Jul. 31, 2018
Line of Credit Facility [Line Items]
Number of shares authorized to be repurchased (in shares)						60,000,000
Stock repurchased and retired during period under repurchase plan, value	$ 578,300,000	$ 1,600,000,000
Stock repurchased and retired during period (in shares)	10,500,000	26,900,000
Stock repurchase program, authorized amount (in shares)	$ 450,000,000	$ 450,000,000			$ 475,000,000
Partial settlement of accelerated share repurchase agreement (in shares)	6,300,000	6,300,000	1,900,000	6,400,000
Accelerated share repurchases, payment	$ 450,000,000	$ 450,000,000		$ 475,000,000
Restriction on payment of dividends, minimum ratio of total capitalization	35.00%	35.00%
Restricted net assets of subsidiaries	$ 5,400,000,000	$ 5,400,000,000
Cash Borrowings
Line of Credit Facility [Line Items]
Debt Instrument, debt to capitalization ratio (no more than)	65.00%	65.00%
Westar Energy
Line of Credit Facility [Line Items]
Restriction on payment of dividends, minimum ratio of total capitalization	40.00%	40.00%
Westar Energy | Cash Borrowings
Line of Credit Facility [Line Items]
Debt Instrument, debt to capitalization ratio (no more than)	65.00%	65.00%
KCP&L
Line of Credit Facility [Line Items]
Restriction on payment of dividends, minimum ratio of total capitalization	40.00%	40.00%
Retained earnings restrictions	$ 471,200,000	$ 471,200,000
KCP&L | Cash Borrowings
Line of Credit Facility [Line Items]
Debt Instrument, debt to capitalization ratio (no more than)	65.00%	65.00%
GMO | Cash Borrowings
Line of Credit Facility [Line Items]
Debt Instrument, debt to capitalization ratio (no more than)	65.00%	65.00%

TAXES - Income Tax Expense (Det

TAXES - Income Tax Expense (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Current income taxes
Federal	$ 11.9	$ 0.2
State	(0.6)	0
Total	11.3	0.2
Deferred income taxes
Federal	(7.3)	5.9
State	6.3	3.7
Total	(1)	9.6
Investment tax credit amortization	(1)	(0.6)
Income tax expense	$ 9.3	$ 9.2
Effective Income Tax Rate Reconciliation, Percent [Abstract]
Federal statutory income tax rate	21.00%	21.00%
Effect of:
COLI policies	(1.80%)	(3.10%)
State income taxes	4.60%	4.20%
Flow through depreciation for plant-related differences	(4.40%)	0.90%
Federal tax credits	(3.90%)	(9.50%)
Non-controlling interest	(0.30%)	(0.50%)
AFUDC equity	0.00%	(0.20%)
Amortization of federal investment tax credits	(0.50%)	(0.60%)
Valuation allowance	(7.00%)	2.10%
Stock compensation	0.10%	(1.10%)
Officer compensation limitation	0.20%	0.00%
Other	0.20%	(0.50%)
Effective income tax rate	8.20%	12.70%
Westar Energy
Current income taxes
Federal	$ 10.4	$ 0.2
State	0.4	0
Total	10.8	0.2
Deferred income taxes
Federal	(3.2)	5.9
State	3.6	3.7
Total	0.4	9.6
Investment tax credit amortization	(0.7)	(0.6)
Income tax expense	$ 10.5	$ 9.2
Effective Income Tax Rate Reconciliation, Percent [Abstract]
Federal statutory income tax rate	21.00%	21.00%
Effect of:
COLI policies	(3.20%)	(3.10%)
State income taxes	5.00%	4.20%
Flow through depreciation for plant-related differences	(0.10%)	0.90%
Federal tax credits	(6.10%)	(9.50%)
Non-controlling interest	(0.60%)	(0.50%)
AFUDC equity	(0.10%)	(0.20%)
Amortization of federal investment tax credits	(0.70%)	(0.60%)
Valuation allowance	(2.10%)	2.10%
Stock compensation	(0.10%)	(1.10%)
Other	0.30%	(0.50%)
Effective income tax rate	13.30%	12.70%
KCP&L
Current income taxes
Federal	$ 7.9	$ (1.3)
State	0.8	(0.5)
Total	8.7	(1.8)
Deferred income taxes
Federal	(5.2)	3.6
State	0.4	2
Total	(4.8)	5.6
Investment tax credit amortization	(0.2)	(0.3)
Income tax expense	$ 3.7	$ 3.5
Effective Income Tax Rate Reconciliation, Percent [Abstract]
Federal statutory income tax rate	21.00%	21.00%
Effect of:
COLI policies	(0.10%)	(0.00%)
State income taxes	4.90%	5.10%
Flow through depreciation for plant-related differences	(7.20%)	(6.90%)
Federal tax credits	(1.50%)	(2.00%)
AFUDC equity	0.00%	(0.30%)
Amortization of federal investment tax credits	(0.30%)	(0.40%)
Stock compensation	1.00%	(0.20%)
Officer compensation limitation	0.30%	0.00%
Other	0.30%	(1.40%)
Effective income tax rate	18.40%	14.90%

LEASES Narrative (Details)

LEASES Narrative (Details)	3 Months Ended
	Mar. 31, 2019
Minimum
Lessee, Lease, Description [Line Items]
Remaining lease term	1 year
Minimum | Westar Energy
Lessee, Lease, Description [Line Items]
Remaining lease term	1 year
Minimum | KCP&L
Lessee, Lease, Description [Line Items]
Remaining lease term	2 years
Maximum
Lessee, Lease, Description [Line Items]
Remaining lease term	20 years
Maximum | Westar Energy
Lessee, Lease, Description [Line Items]
Remaining lease term	20 years
Maximum | KCP&L
Lessee, Lease, Description [Line Items]
Remaining lease term	27 years

LEASES - Schedule of Lease Expe

LEASES - Schedule of Lease Expense (Details) $ in Millions	3 Months Ended
	Mar. 31, 2019USD ($)
Finance lease costs
Amortization of right-of-use assets	$ 1.1
Interest on lease liabilities	0.7
Operating lease costs	6.4
Short-term lease costs	0.8
Variable lease costs for renewable purchase power agreements	73.9
Total lease costs	82.9
Westar Energy
Finance lease costs
Amortization of right-of-use assets	1
Interest on lease liabilities	0.6
Operating lease costs	3.8
Short-term lease costs	0.1
Variable lease costs for renewable purchase power agreements	32.2
Total lease costs	37.7
KCP&L
Finance lease costs
Amortization of right-of-use assets	0
Interest on lease liabilities	0
Operating lease costs	2.3
Short-term lease costs	0.7
Variable lease costs for renewable purchase power agreements	29.1
Total lease costs	$ 32.1

LEASES - Supplemental Cash Flow

LEASES - Supplemental Cash Flow Information (Details) $ in Millions	3 Months Ended
	Mar. 31, 2019USD ($)
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows from operating leases	$ 5.8
Operating cash flows from finance leases	0.7
Financing cash flows from finance leases	1.1
Right-of-use assets obtained in exchange for new operating lease liabilities	2.2
Right-of-use assets obtained in exchange for new finance lease liabilities	2.3
Westar Energy
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows from operating leases	3.4
Operating cash flows from finance leases	0.6
Financing cash flows from finance leases	1.1
Right-of-use assets obtained in exchange for new operating lease liabilities	0
Right-of-use assets obtained in exchange for new finance lease liabilities	2.3
KCP&L
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows from operating leases	2.4
Operating cash flows from finance leases	0
Financing cash flows from finance leases	0
Right-of-use assets obtained in exchange for new operating lease liabilities	2.2
Right-of-use assets obtained in exchange for new finance lease liabilities	$ 0

LEASES - Schedule of Future Pay

LEASES - Schedule of Future Payments for Finance Leases (Details) $ in Millions	Mar. 31, 2019USD ($)
Lessee, Lease, Description [Line Items]
2019	$ 5.4
2020	7
2021	6.5
2022	5.7
2023	4.8
After 2023	48.4
Total finance lease payments	77.8
Amounts representing imputed interest	(27.6)
Present value of lease payments	50.2
Less: current portion	(4.2)
Total long-term obligations under finance leases	$ 46
Weighted-average lease term (years)	15 years 5 months 1 day
Weighted-average discount rate	5.70%
Westar Energy
Lessee, Lease, Description [Line Items]
2019	$ 5.1
2020	6.6
2021	6
2022	5.2
2023	4.4
After 2023	46.4
Total finance lease payments	73.7
Amounts representing imputed interest	(26.4)
Present value of lease payments	47.3
Less: current portion	(4)
Total long-term obligations under finance leases	$ 43.3
Weighted-average lease term (years)	15 years 9 months
Weighted-average discount rate	5.60%
KCP&L
Lessee, Lease, Description [Line Items]
2019	$ 0.2
2020	0.2
2021	0.2
2022	0.2
2023	0.2
After 2023	1
Total finance lease payments	2
Amounts representing imputed interest	(0.6)
Present value of lease payments	1.4
Less: current portion	(0.1)
Total long-term obligations under finance leases	$ 1.3
Weighted-average lease term (years)	9 years 5 months 1 day
Weighted-average discount rate	7.60%

LEASES - Estimated Future Commi

LEASES - Estimated Future Commitments Under Finance Leases (Details) $ in Millions	Dec. 31, 2018USD ($)
Lessee, Lease, Description [Line Items]
2019	$ 6.4
2020	5.8
2021	5.3
2022	4.7
2023	4
After 2023	48.6
Total finance lease payments	74.8
Amounts representing imputed interest	(25.8)
Present value of net minimum lease payments under finance leases	49
Less: current portion	(3.9)
Total long-term obligations under finance leases	45.1
Westar Energy
Lessee, Lease, Description [Line Items]
2019	6
2020	5.4
2021	4.9
2022	4.3
2023	3.6
After 2023	46.4
Total finance lease payments	70.6
Amounts representing imputed interest	(24.6)
Present value of net minimum lease payments under finance leases	46
Less: current portion	(3.7)
Total long-term obligations under finance leases	42.3
KCP&L
Lessee, Lease, Description [Line Items]
2019	0.2
2020	0.2
2021	0.2
2022	0.2
2023	0.2
After 2023	1.1
Total finance lease payments	2.1
Amounts representing imputed interest	(0.6)
Present value of net minimum lease payments under finance leases	1.5
Less: current portion	(0.1)
Total long-term obligations under finance leases	$ 1.4

LEASES - Lease Payments for Ope

LEASES - Lease Payments for Operating Leases (Details) $ in Millions	Mar. 31, 2019USD ($)
Lessee, Lease, Description [Line Items]
2019	$ 15.6
2020	18.7
2021	15.3
2022	12.4
2023	9.4
After 2023	52.4
Total operating lease payments	123.8
Amounts representing imputed interest	(20.8)
Present value of lease payments	103
Less: current portion	(16.1)
Total long-term obligations under operating leases	$ 86.9
Weighted-average lease term (years)	9 years 4 months 1 day
Weighted-average discount rate	3.90%
Westar Energy
Lessee, Lease, Description [Line Items]
2019	$ 9.5
2020	10.2
2021	7.3
2022	5.1
2023	2.6
After 2023	2.8
Total operating lease payments	37.5
Amounts representing imputed interest	(2.7)
Present value of lease payments	34.8
Less: current portion	(10.5)
Total long-term obligations under operating leases	$ 24.3
Weighted-average lease term (years)	4 years 2 months 1 day
Weighted-average discount rate	3.40%
KCP&L
Lessee, Lease, Description [Line Items]
2019	$ 7.6
2020	10.6
2021	10.1
2022	9.3
2023	8.8
After 2023	91.3
Total operating lease payments	137.7
Amounts representing imputed interest	(38.4)
Present value of lease payments	99.3
Less: current portion	(6.3)
Total long-term obligations under operating leases	$ 93
Weighted-average lease term (years)	16 years 2 months 1 day
Weighted-average discount rate	4.10%

LEASES - Estimated Future Com_2

LEASES - Estimated Future Commitments Under Operating Leases (Details) $ in Millions	Dec. 31, 2018USD ($)
Lessee, Lease, Description [Line Items]
2019	$ 24.2
2020	20.7
2021	18.4
2022	15.2
2023	12.4
After 2023	95
Total operating lease payments	185.9
Westar Energy
Lessee, Lease, Description [Line Items]
2019	14
2020	10.1
2021	8.1
2022	5.2
2023	2.8
After 2023	3.1
Total operating lease payments	43.3
KCP&L
Lessee, Lease, Description [Line Items]
2019	10.2
2020	10.6
2021	10.3
2022	10
2023	9.6
After 2023	91.8
Total operating lease payments	$ 142.5