The carrying value per unit of an equity method investment at the balance sheet date.

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Equity Method Investment, Ownership, Shares

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Entity's interest in incentive distribution rights held by the general partner.

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Represents the percentage of management rights in the general partner of Enable

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Represents the number of days notice required prior to the end of the extension term to terminate the Services Agreement

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Represents the number of days notice required upon board of director’s approval to terminate either any service provided under the Services Agreement or the entire Services Agreement.

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Amount for accounts payable to related parties. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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For an unclassified balance sheet, amount of receivables arising from transactions with related parties.

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Costs associated with revenues arising from an entity that is an affiliate of the reporting entity by means of direct or indirect ownership.

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Maximum contractual interest rate for funds borrowed, under the debt agreement.

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Minimum contractual interest rate for funds borrowed, under the debt agreement.

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The aggregate amount of receivables to be collected from related parties where one party can exercise control or significant influence over another party; including affiliates, owners or officers and their immediate families, pension trusts, and so forth, at the financial statement date. which are usually due within one year (or one business cycle).

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Gross amount of debt extinguished.

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Amount of interest income earned from interest-bearing assets owed to the entity by related party.

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Repayment received or receivable for expenses incurred on behalf of a client or customer, other than those reimbursements received by landlords from tenants.

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Price of a single share of a number of saleable stocks of a company.

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Unconsolidated Affiliates Description (Details) - USD ($) $ / shares in Units, $ in Millions		3 Months Ended		6 Months Ended
	Feb. 18, 2016	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015	Dec. 31, 2015
Interest receivable		$ 12		$ 12		$ 8
Service Agreement Notice For Termination At Term End, Number Of Days				90 days
Service Agreement Notice For Termination At Will Number Of Days				180 days
Enable Midstream Partners [Member]
Share Price		$ 13.51		$ 13.51
Enable Midstream Partners [Member]
Equity Method Investment, Ownership Percentage		55.40%		55.40%
Equity Method Investment, Carrying Value Per Unit		$ 10.85		$ 10.85
Subordinated Units [Member] \| Enable Midstream Partners [Member]
Equity Method Investment, Ownership, Shares		139,704,916		139,704,916
Common Stock [Member] \| Enable Midstream Partners [Member]
Equity Method Investment, Ownership, Shares		94,151,707		94,151,707
Enable Midstream Partners [Member]
Extinguishment of Debt, Amount	$ 363
Debt Instrument, Interest Rate, Stated Percentage Rate Range, Minimum				2.10%
Debt Instrument, Interest Rate, Stated Percentage Rate Range, Maximum				2.45%
Interest Income, Related Party		$ 0	$ 2	$ 1	$ 4
Interest receivable		0		0		4
Transitional Service [Member] \| Enable Midstream Partners [Member]
Reimbursement Revenue		2	2	5	7
Accounts Receivable, Related Parties		1		1		3
Natural Gas Expenses [Member] \| Enable Midstream Partners [Member]
Affiliate Costs		24	$ 26	57	$ 65
Accounts Payable, Related Parties, Current		$ 8		$ 8		$ 11
Enable Midstream Partners [Member] \| CERC Corp [Member]
Management Rights Ownership Percentage				50.00%
Incentive Distribution Right				40.00%
Enable Midstream Partners [Member] \| OGE [Member]
Management Rights Ownership Percentage				50.00%
Incentive Distribution Right				60.00%