Retirement Plans and Postretirement Benefit Plans - Schedule of Capitalized Pension and Postretirement Cost (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Capitalized portion of net periodic pension benefit cost	$ 0.6	$ 0.8
Pension Plan [Member] | OG&E [Member]
Defined Benefit Plan Disclosure [Line Items]
Capitalized portion of net periodic pension benefit cost	0.5	0.7
Other Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Capitalized portion of net periodic pension benefit cost	0.0	0.1
Other Postretirement Benefits Plan [Member] | OG&E [Member]
Defined Benefit Plan Disclosure [Line Items]
Capitalized portion of net periodic pension benefit cost	$ 0.0	$ 0.0