Retirement Plans and Postretirement Benefit Plans - Schedule of Accumulated Benefit Obligations in Excess of Fair Value of Plan Assets (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Employer contributions		$ 40.0
Og and E [Member]
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Employer contributions		30.0
Pension Plans [Member]
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Benefit Obligation, Beginning	$ 502.9	654.6
Service cost	7.6	11.2
Interest cost	15.7	13.3
Plan settlements	(95.8)	(158.6)
Plan amendments	0.0	0.0
Plan curtailments	0.0	0.0
Actuarial (gains) losses	(56.9)	(3.5)
Benefits paid	(15.0)	(14.1)
Benefit Obligation, Ending	358.5	502.9	$ 654.6
Pension Plans [Member] | Og and E [Member]
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Benefit Obligation, Beginning	363.2	484.1
Service cost	6.2	7.7
Interest cost	12.1	9.7
Plan settlements	(38.8)	(120.4)
Plan amendments	0.0	0.0
Plan curtailments	0.0	0.0
Actuarial (gains) losses	(41.3)	(6.0)
Benefits paid	(12.9)	(11.9)
Benefit Obligation, Ending	288.5	363.2	484.1
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair Value of Plan Assets, Beginning	353.0	420.3
Actual return on plans' assets	(62.4)	35.0
Employer contributions	0.0	30.0
Plan settlements	(38.8)	(120.4)
Benefits paid	(12.9)	(11.9)
Fair Value of Plan Assets, Ending	238.9	353.0	420.3
Funded status at end of year	(49.6)	(10.2)
Accumulated Benefit Obligation	(275.2)	(341.0)
Pension Plans, Defined Benefit [Member]
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Service cost	7.6	11.2	13.2
Interest cost	15.7	13.3	17.0
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair Value of Plan Assets, Beginning	486.0	570.3
Actual return on plans' assets	(82.2)	48.4
Employer contributions	0.0	40.0
Plan settlements	(95.8)	(158.6)
Benefits paid	(15.0)	(14.1)
Fair Value of Plan Assets, Ending	293.0	486.0	570.3
Funded status at end of year	(65.5)	(16.9)
Accumulated Benefit Obligation	(342.7)	(475.2)
Pension Plans, Defined Benefit [Member] | Og and E [Member]
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Service cost	6.2	7.7	9.2
Interest cost	12.1	9.7	12.6
Restoration of Retirement Income Plan [Member]
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Benefit Obligation, Beginning	5.9	7.8
Service cost	1.1	0.8	0.8
Interest cost	0.2	0.1	0.2
Plan settlements	(1.5)	(4.6)
Plan amendments	0.0	1.4
Plan curtailments	0.0	(0.1)
Actuarial (gains) losses	0.1	0.5
Benefits paid	0.0	0.0
Benefit Obligation, Ending	5.8	5.9	7.8
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair Value of Plan Assets, Beginning	0.0	0.0
Actual return on plans' assets	0.0	0.0
Employer contributions	0.2	4.6
Plan settlements	(0.2)	(4.6)
Benefits paid	0.0	0.0
Fair Value of Plan Assets, Ending	0.0	0.0	0.0
Funded status at end of year	(5.8)	(5.9)
Accumulated Benefit Obligation	(4.8)	(5.4)
Restoration of Retirement Income Plan [Member] | Og and E [Member]
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Benefit Obligation, Beginning	0.5	3.0
Service cost	0.0	0.0	0.1
Interest cost	0.0	0.0	0.1
Plan settlements	0.0	(2.9)
Plan amendments	0.0	0.0
Plan curtailments	0.0	0.0
Actuarial (gains) losses	0.0	0.4
Benefits paid	0.0	0.0
Benefit Obligation, Ending	0.5	0.5	3.0
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair Value of Plan Assets, Beginning	0.0	0.0
Actual return on plans' assets	0.0	0.0
Employer contributions	0.0	2.9
Plan settlements	0.0	(2.9)
Benefits paid	0.0	0.0
Fair Value of Plan Assets, Ending	0.0	0.0	0.0
Funded status at end of year	(0.5)	(0.5)
Accumulated Benefit Obligation	(0.4)	(0.4)
Other Postretirement Benefits Plan [Member]
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Benefit Obligation, Beginning	137.3	144.5
Service cost	0.2	0.2	0.2
Interest cost	3.5	3.4	4.2
Plan curtailments	0.0	1.9
Participants' contributions	3.5	3.5
Actuarial (gains) losses	(29.1)	(3.7)
Benefits paid	(13.5)	(12.5)
Benefit Obligation, Ending	101.9	137.3	144.5
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair Value of Plan Assets, Beginning	44.3	47.6
Actual return on plans' assets	(8.2)	(0.5)
Employer contributions	6.7	6.2
Participants' contributions	3.5	3.5
Benefits paid	(13.5)	(12.5)
Fair Value of Plan Assets, Ending	32.8	44.3	47.6
Accumulated Benefit Obligation	(69.1)	(93.0)
Other Postretirement Benefits Plan [Member] | Og and E [Member]
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Benefit Obligation, Beginning	102.4	109.5
Service cost	0.1	0.1	0.2
Interest cost	2.7	2.6	3.2
Plan curtailments	0.0	0.0
Participants' contributions	2.4	2.6
Actuarial (gains) losses	(21.0)	(2.5)
Benefits paid	(10.2)	(9.9)
Benefit Obligation, Ending	76.4	102.4	109.5
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair Value of Plan Assets, Beginning	39.9	42.7
Actual return on plans' assets	(7.4)	(0.5)
Employer contributions	5.1	5.0
Participants' contributions	2.4	2.6
Benefits paid	(10.2)	(9.9)
Fair Value of Plan Assets, Ending	29.8	39.9	$ 42.7
Accumulated Benefit Obligation	$ (46.6)	$ (62.5)