Expected Settlement Charge

No definition available.

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Balance Type:	debit
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- Definition

Amount of receivables arising from transactions with related parties due within one year or the normal operating cycle, if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
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Balance Type:	debit
Period Type:	instant

- Definition

Amount of paid and unpaid common stock dividends declared with the form of settlement in cash, stock and payment-in-kind (PIK).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
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Period Type:	duration

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Purchases during the period (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of selling, general and administrative expenses resulting from transactions, excluding transactions that are eliminated in consolidated or combined financial statements, with related party.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of revenue, fees and commissions earned from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, for example, but not limited to, pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 220
-Section S99
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- Details

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- Details

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- Details

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Related Party Disclosures (Details) - USD ($) $ in Millions	12 Months Ended
Related Party Disclosures (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Related Party Transaction [Line Items]
Expected Settlement Charge	$ 19.0
Excluding Fuel Purchases [Member]
Related Party Transaction [Line Items]
Accounts receivable - unconsolidated affiliates	2.0	$ 0.8
Og and E [Member]
Related Party Transaction [Line Items]
Dividends, Common Stock	325.0		$ 185.0
Og and E [Member] \| Retained Earnings
Related Party Transaction [Line Items]
Dividends, Common Stock	(325.0)	0.0	185.0
Enable Midstream Partners [Member] \| Og and E [Member]
Related Party Transaction [Line Items]
Revenue from Related Parties	15.1	15.9	16.3
Enable Midstream Partners [Member] \| Og and E [Member] \| Natural Gas Transportation [Member]
Related Party Transaction [Line Items]
Related Party Transaction, Purchases from Related Party	32.8	41.2	37.9
Enable Midstream Partners [Member] \| Og and E [Member] \| Natural Gas Purchases [Member]
Related Party Transaction [Line Items]
Related Party Transaction, Purchases from Related Party	2.7	(6.0)	(3.2)
Enable Midstream Partners [Member] \| OGE Energy [Member] \| Operating Costs Charged [Member]
Related Party Transaction [Line Items]
Related Party Transaction, Selling, General and Administrative Expenses from Transactions with Related Party	0.4	0.5	0.6
Enable Midstream Partners [Member] \| OGE Energy [Member] \| Employment Costs [Member]
Related Party Transaction [Line Items]
Related Party Transaction, Selling, General and Administrative Expenses from Transactions with Related Party	17.3	23.2	27.5
Og and E [Member] \| OGE Energy [Member]
Related Party Transaction [Line Items]
Related Party Transaction, Selling, General and Administrative Expenses from Transactions with Related Party	$ 140.6	$ 149.8	$ 140.9