Summary of Significant Accounting Policies (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Summary of Accounting Policies [Line Items]
Regulatory liabilities	$ 734	$ 669
Capitalized Interest Costs, Including Allowance for Funds Used During Construction	2	1	$ 1
Provision for doubtful accounts	19	20	20
Write-down of natural gas inventory	4	8	$ 4
Inventory	213	252
Deferred Tax Asset, Reclassified to Noncurrent Deferred Tax Liability		1
Margin deposits	31	19
Under Recovered Gas Costs	12	45
Over Recovered Gas Costs	$ 55	37
Enable Midstream Partners [Member]
Summary of Accounting Policies [Line Items]
Variable Interest Entity, Qualitative or Quantitative Information, Ownership Percentage	55.40%
Management Rights Ownership Percentage	50.00%
Incentive Distribution Right	40.00%
Incentive Distribution Right, Maximum	50.00%
Enable Midstream Partners [Member] | OGE [Member]
Summary of Accounting Policies [Line Items]
Variable Interest Entity, Qualitative or Quantitative Information, Ownership Percentage	26.30%
Management Rights Ownership Percentage	50.00%
Incentive Distribution Right	60.00%
Minimum [Member] | Enable Midstream Partners [Member]
Summary of Accounting Policies [Line Items]
Incentive Distribution, Distribution Per Unit	$ 0.2875
Maximum [Member] | Enable Midstream Partners [Member]
Summary of Accounting Policies [Line Items]
Incentive Distribution, Distribution Per Unit	$ 0.330625
Removal Costs [Member]
Summary of Accounting Policies [Line Items]
Regulatory liabilities	$ 632	605
Materials And Supplies [Member]
Summary of Accounting Policies [Line Items]
Inventory	45	41
Public Utilities, Inventory, Natural Gas [Member]
Summary of Accounting Policies [Line Items]
Inventory	168	211
Other Noncurrent Assets [Member]
Summary of Accounting Policies [Line Items]
Unamortized Debt Issuance Expense	$ 15	$ 18