Income Taxes - Summary of Tax Credit Carryforwards (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Income Taxes [Line Items]
State tax credits	$ (228.8)	$ (221.2)
Og and E [Member]
Income Taxes [Line Items]
State tax credits	(213.5)	$ (208.5)
Oklahoma investment tax credits [Member]
Income Taxes [Line Items]
Tax Credit Carryforward, Amount	259.1
State tax credits	204.7
Oklahoma investment tax credits [Member] | Og and E [Member]
Income Taxes [Line Items]
Tax Credit Carryforward, Amount	239.8
State tax credits	189.4
Oklahoma capital investment board credits [Member]
Income Taxes [Line Items]
Tax Credit Carryforward, Amount	12.8
State tax credits	12.8
Oklahoma capital investment board credits [Member] | Og and E [Member]
Income Taxes [Line Items]
Tax Credit Carryforward, Amount	12.8
State tax credits	12.8
Oklahoma zero emission tax credits [Member]
Income Taxes [Line Items]
Tax Credit Carryforward, Amount	16.0
State tax credits	11.3
Oklahoma zero emission tax credits [Member] | Og and E [Member]
Income Taxes [Line Items]
Tax Credit Carryforward, Amount	16.0
State tax credits	$ 11.3