Commitments and Contingencies - Unrecorded Unconditional Purchase Obligations Disclosure (Details) $ in Millions	Dec. 31, 2023 USD ($)
Loss Contingencies [Line Items]
Purchase Obligation, Due in Next Twelve Months	$ 348.7
Unrecorded Unconditional Purchase Obligation, Due within Two Years	344.8
Unrecorded Unconditional Purchase Obligation, Due within Three Years	222.1
Unrecorded Unconditional Purchase Obligation, Due within Four Years	166.0
Unrecorded Unconditional Purchase Obligation, Due within Five Years	108.0
Unrecorded Unconditional Purchase Obligation, Total	1,189.6
OG&E minimum fuel purchase commitments [Member]
Loss Contingencies [Line Items]
Purchase Obligation, Due in Next Twelve Months	118.4
Unrecorded Unconditional Purchase Obligation, Due within Two Years	100.5
Unrecorded Unconditional Purchase Obligation, Due within Three Years	69.7
Unrecorded Unconditional Purchase Obligation, Due within Four Years	56.9
Unrecorded Unconditional Purchase Obligation, Due within Five Years	46.6
Unrecorded Unconditional Purchase Obligation, Total	392.1
OG&E Estimated Wind Purchase Commitments [Member]
Loss Contingencies [Line Items]
Purchase Obligation, Due in Next Twelve Months	56.6
Unrecorded Unconditional Purchase Obligation, Due within Two Years	56.9
Unrecorded Unconditional Purchase Obligation, Due within Three Years	57.3
Unrecorded Unconditional Purchase Obligation, Due within Four Years	57.8
Unrecorded Unconditional Purchase Obligation, Due within Five Years	58.4
Unrecorded Unconditional Purchase Obligation, Total	287.0
OG&E Capacity Commitments [Member]
Loss Contingencies [Line Items]
Purchase Obligation, Due in Next Twelve Months	32.4
Unrecorded Unconditional Purchase Obligation, Due within Two Years	33.0
Unrecorded Unconditional Purchase Obligation, Due within Three Years	40.2
Unrecorded Unconditional Purchase Obligation, Due within Four Years	41.4
Unrecorded Unconditional Purchase Obligation, Due within Five Years	0.0
Unrecorded Unconditional Purchase Obligation, Total	147.0
OG&E long-term service agreement commitments [Member]
Loss Contingencies [Line Items]
Purchase Obligation, Due in Next Twelve Months	14.8
Unrecorded Unconditional Purchase Obligation, Due within Two Years	16.6
Unrecorded Unconditional Purchase Obligation, Due within Three Years	16.6
Unrecorded Unconditional Purchase Obligation, Due within Four Years	9.9
Unrecorded Unconditional Purchase Obligation, Due within Five Years	3.0
Unrecorded Unconditional Purchase Obligation, Total	60.9
OG&E Generation Capacity Construction Commitments [Member]
Loss Contingencies [Line Items]
Purchase Obligation, Due in Next Twelve Months	126.5
Unrecorded Unconditional Purchase Obligation, Due within Two Years	137.8
Unrecorded Unconditional Purchase Obligation, Due within Three Years	38.3
Unrecorded Unconditional Purchase Obligation, Due within Four Years	0.0
Unrecorded Unconditional Purchase Obligation, Due within Five Years	0.0
Unrecorded Unconditional Purchase Obligation, Total	$ 302.6