XML 61 R51.htm IDEA: XBRL DOCUMENT
v3.23.3

Retirement Plans and Postretirement Benefit Plans (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2023 | Sep. 30, 2022 | Sep. 30, 2023 | Sep. 30, 2022
Pension Plan [Member] |  |  |  |  |  |  |  |  |
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract] |  |  |  |  |  |  |  |  |
Service cost |  | $ 1.3 |  | $ 1.8 |  | $ 4.0 |  | $ 5.7 |
Interest cost |  | 4.1 |  | 4.1 |  | 12.0 |  | 11.8 |
Expected return on plan assets |  | (4.0) |  | (6.0) |  | (12.2) |  | (19.0) |
Amortization of net (gain) loss |  | 1.8 |  | 2.4 |  | 6.0 |  | 6.6 |
Defined Benefit Plan, Amortization of Prior Service Cost (Credit) |  | 0.0 | [1] | 0.0 | [1] | 0.0 | [1] | 0.0 | [2]
Settlement cost |  | 1.7 |  | 2.3 |  | 21.1 |  | 18.3 |
Total net periodic benefit cost |  | 4.9 |  | 4.6 |  | 30.9 |  | 23.4 |
Capitalized portion of net periodic pension benefit cost |  | 0.6 |  | 0.7 |  | 1.7 |  | 2.2 |
Other Pension Plan [Member] |  |  |  |  |  |  |  |  |
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract] |  |  |  |  |  |  |  |  |
Service cost |  | 0.2 |  | 0.3 |  | 0.7 |  | 0.8 |
Interest cost |  | 0.1 |  | 0.0 |  | 0.2 |  | 0.1 |
Expected return on plan assets |  | 0.0 |  | 0.0 |  | 0.0 |  | 0.0 |
Amortization of net (gain) loss |  | 0.0 |  | 0.0 |  | 0.0 |  | 0.1 |
Defined Benefit Plan, Amortization of Prior Service Cost (Credit) | [1] | 0.1 |  | 0.1 |  | 0.3 |  | 0.2 |
Settlement cost |  | 0.1 |  | 0.0 |  | 0.1 |  | 0.2 |
Total net periodic benefit cost |  | 0.5 |  | 0.4 |  | 1.3 |  | 1.4 |
Postretirement Benefit Plan [Member] |  |  |  |  |  |  |  |  |
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract] |  |  |  |  |  |  |  |  |
Service cost |  | 0.1 |  | 0.0 |  | 0.1 |  | 0.1 |
Interest cost |  | 1.3 |  | 0.9 |  | 3.9 |  | 2.7 |
Expected return on plan assets |  | (0.5) |  | (0.5) |  | (1.3) |  | (1.4) |
Amortization of net (gain) loss |  | (0.1) |  | 0.5 |  | (0.2) |  | 1.2 |
Defined Benefit Plan, Amortization of Prior Service Cost (Credit) |  | 0.0 | [2] | (1.0) | [2] | 0.0 | [1] | (2.9) | [1]
Total net periodic benefit cost |  | 0.8 |  | (0.1) |  | 2.5 |  | (0.3) |
Net periodic benefit cost (income) |  | 0.8 |  | (0.1) |  | 2.5 |  | (0.3) |
Capitalized portion of net periodic pension benefit cost |  | 0.0 |  | 0.1 |  | 0.1 |  | 0.2 |
OG&E [Member] | Pension Plan [Member] |  |  |  |  |  |  |  |  |
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract] |  |  |  |  |  |  |  |  |
Service cost |  | 1.1 |  | 1.5 |  | 3.3 |  | 4.6 |
Interest cost |  | 3.1 |  | 3.1 |  | 9.4 |  | 9.0 |
Expected return on plan assets |  | (3.1) |  | (4.7) |  | (9.6) |  | (14.7) |
Amortization of net (gain) loss |  | 1.6 |  | 2.1 |  | 5.2 |  | 5.6 |
Settlement cost |  | 1.7 |  | 0.4 |  | 19.7 |  | 6.1 |
Total net periodic benefit cost |  | 4.4 |  | 2.4 |  | 28.0 |  | 10.6 |
Net periodic benefit cost (income) |  | 4.9 |  | 2.8 |  | 30.5 |  | 13.2 |
Capitalized portion of net periodic pension benefit cost |  | 0.4 |  | 0.7 |  | 1.4 |  | 1.9 |
Amount Attributable to Parent |  | 0.5 |  | 0.4 |  | 2.5 |  | 2.6 |
OG&E [Member] | Other Pension Plan [Member] |  |  |  |  |  |  |  |  |
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract] |  |  |  |  |  |  |  |  |
Service cost |  | 0.0 |  | 0.0 |  | 0.0 |  | 0.0 |
Interest cost |  | 0.0 |  | 0.0 |  | 0.0 |  | 0.0 |
Expected return on plan assets |  | 0.0 |  | 0.0 |  | 0.0 |  | 0.0 |
Amortization of net (gain) loss |  | 0.0 |  | 0.0 |  | 0.0 |  | 0.0 |
Settlement cost |  | 0.1 |  | 0.0 |  | 0.1 |  | 0.0 |
Total net periodic benefit cost |  | 0.1 |  | 0.0 |  | 0.1 |  | 0.0 |
Net periodic benefit cost (income) |  | 0.5 |  | 0.4 |  | 1.2 |  | 1.1 |
Amount Attributable to Parent |  | 0.4 |  | 0.4 |  | 1.1 |  | 1.1 |
OG&E [Member] | Postretirement Benefit Plan [Member] |  |  |  |  |  |  |  |  |
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract] |  |  |  |  |  |  |  |  |
Service cost |  | 0.0 |  | 0.0 |  | 0.0 |  | 0.1 |
Interest cost |  | 0.9 |  | 0.7 |  | 2.9 |  | 2.0 |
Expected return on plan assets |  | (0.3) |  | (0.4) |  | (1.1) |  | (1.2) |
Amortization of net (gain) loss |  | 0.0 |  | 0.3 |  | 0.0 |  | 1.1 |
Defined Benefit Plan, Amortization of Prior Service Cost (Credit) | [1] | 0.0 |  | (0.9) |  | 0.0 |  | (2.7) |
Total net periodic benefit cost |  | 0.6 |  | (0.3) |  | 1.8 |  | (0.7) |
Net periodic benefit cost (income) |  | 0.7 |  | (0.3) |  | 2.2 |  | (0.7) |
Capitalized portion of net periodic pension benefit cost |  | 0.0 |  | 0.0 |  | 0.1 |  | 0.1 |
Amount Attributable to Parent |  | 0.1 |  | 0.0 |  | 0.4 |  | 0.0 |
OKLAHOMA | Pension Plan [Member] |  |  |  |  |  |  |  |  |
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract] |  |  |  |  |  |  |  |  |
Settlement cost |  | 1.7 | [3] | 0.3 | [3] | 19.1 | [4] | 7.0 | [4]
Change in regulatory asset related to pension expense to maintain allowed recoverable amount in Oklahoma jurisdiction (A) |  | 5.0 | [3] | 2.7 | [3] | 29.0 | [4] | 5.0 | [4]
OKLAHOMA | Postretirement Benefit Plan [Member] |  |  |  |  |  |  |  |  |
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract] |  |  |  |  |  |  |  |  |
Change in regulatory asset related to pension expense to maintain allowed recoverable amount in Oklahoma jurisdiction (A) | [4] | 1.1 |  | (0.2) |  | 3.3 |  | (0.4) |
ARKANSAS | Pension Plan [Member] |  |  |  |  |  |  |  |  |
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract] |  |  |  |  |  |  |  |  |
Settlement cost |  | $ 0.2 | [3] | $ 0.1 | [3] | $ 1.8 | [4] | $ 0.7 | [4]
[1] | Unamortized prior service cost is amortized on a straight-line basis over the average remaining service period to the first eligibility age of participants who are expected to receive a benefit and are active at the date of the plan amendment.
[2] | Unamortized prior service cost is amortized on a straight-line basis over the average remaining service period to the first eligibility age of participants who are expected to receive a benefit and are active at the date of the plan amendment.
[3] | Included in the pension regulatory asset in each jurisdiction, as presented in the regulatory assets and liabilities table in Note 1.
[4] | Included in the pension regulatory asset or liability in each jurisdiction, as presented in the regulatory assets and liabilities table in Note 1.

X
- Definition Additional Pension Expense to Meet State Requirements + References No definition available. + Details
Name: | oge_AdditionalPensionExpenseToMeetStateRequirements
Namespace Prefix: | oge_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount Attributable to Parent + References No definition available. + Details
Name: | oge_AmountAttributableToParent
Namespace Prefix: | oge_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Capitalized Portion of Net Periodic Benefit Cost + References No definition available. + Details
Name: | oge_CapitalizedPortionOfNetPeriodicBenefitCost
Namespace Prefix: | oge_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Net of Unconsolidated Affiliates + References No definition available. + Details
Name: | oge_DefinedBenefitPlanNetPeriodicBenefitCostCreditNetofUnconsolidatedAffiliates
Namespace Prefix: | oge_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of gain (loss) recognized in net periodic benefit (cost) credit of defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 17 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480482/715-20-55-17 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 3A -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480535/715-20-45-3A Reference 3: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 18 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480482/715-20-55-18 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (h)(4) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Subparagraph (a)(4) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-6 + Details
Name: | us-gaap_DefinedBenefitPlanAmortizationOfGainsLosses
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of prior service cost (credit) recognized in net periodic benefit cost (credit) of defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 17 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480482/715-20-55-17 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 3A -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480535/715-20-45-3A Reference 3: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 18 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480482/715-20-55-18 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (h)(5) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Subparagraph (a)(5) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-6 + Details
Name: | us-gaap_DefinedBenefitPlanAmortizationOfPriorServiceCostCredit
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of expected return (loss) recognized in net periodic benefit (cost) credit, calculated based on expected long-term rate of return and market-related value of plan assets of defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 17 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480482/715-20-55-17 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 3A -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480535/715-20-45-3A Reference 3: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 18 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480482/715-20-55-18 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (h)(3) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Subparagraph (a)(3) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-6 + Details
Name: | us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of cost recognized for passage of time related to defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 17 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480482/715-20-55-17 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 3A -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480535/715-20-45-3A Reference 3: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 18 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480482/715-20-55-18 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (a)(2) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (h)(2) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Subparagraph (a)(2) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-6 + Details
Name: | us-gaap_DefinedBenefitPlanInterestCost
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of net periodic benefit cost (credit) for defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 17 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480482/715-20-55-17 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 18 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480482/715-20-55-18 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (h) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-6 + Details
Name: | us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- References No definition available. + Details
Name: | us-gaap_DefinedBenefitPlanNetPeriodicBenefitCostAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of gain (loss) recognized in net periodic benefit (cost) credit from irrevocable action relieving primary responsibility for benefit obligation and eliminating risk related to obligation and assets used to effect settlement. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 3A -Publisher FASB -URI https://asc.fasb.org//1943274/2147480535/715-20-45-3A Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (h)(7) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Subparagraph (a)(7) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-6 + Details
Name: | us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToSettlements1
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of cost for actuarial present value of benefits attributed to service rendered by employee for defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 17 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480482/715-20-55-17 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 18 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480482/715-20-55-18 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (a)(1) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (h)(1) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Subparagraph (a)(1) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-6 + Details
Name: | us-gaap_DefinedBenefitPlanServiceCost
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Details
Name: | us-gaap_RetirementPlanTypeAxis=us-gaap_PensionPlansDefinedBenefitMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RetirementPlanTypeAxis=us-gaap_OtherPensionPlansDefinedBenefitMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RetirementPlanTypeAxis=us-gaap_OtherPostretirementBenefitPlansDefinedBenefitMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | dei_LegalEntityAxis=oge_OgAndEMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | dei_EntityByLocationAxis=stpr_OK
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | dei_EntityByLocationAxis=stpr_AR
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |