Expected Settlement Charge

No definition available.

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- Definition

Increase in Fair Value of Net Assets

+ References

No definition available.

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- Definition

Limited Partner Units Owned

+ References

No definition available.

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- Definition

Percentage of Enogex LLC Contributed

+ References

No definition available.

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- Definition

Per unit of ownership amount of cash distributions declared to unit-holder of a limited partnership (LP).

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- Definition

Difference between amount at which an investment accounted for under the equity method of accounting is carried (reported) on the balance sheet and amount of underlying equity in net assets the reporting Entity has in the investee.

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- Definition

Amount of distribution received from equity method investee for return on investment, classified as operating activities. Excludes distribution for return of investment, classified as investing activities.

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- Definition

This item represents the entity's proportionate share for the period of the net income (loss) of its investee (such as unconsolidated subsidiaries and joint ventures) to which the equity method of accounting is applied. This item includes income or expense related to stock-based compensation based on the investor's grant of stock to employees of an equity method investee.

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- Definition

Percentage investment held by members or limited partners of limited liability company (LLC) or limited partnership (LP).

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Investment in Unconsolidated Affiliates (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017	May 01, 2013
Expected Settlement Charge			$ 12.3
Limited Partner Units Owned	111.0		111.0
Distribution Made to Limited Partner, Distributions Declared, Per Unit			$ 0.31800
Equity in earnings of unconsolidated affiliates	$ 40.1	$ 33.6	$ 103.3	$ 98.6
Equity Method Investment, Difference Between Carrying Amount and Underlying Equity	689.7		689.7		$ 714.2
Enogex LLC [Member]
Percentage of Enogex LLC Contributed						100.00%
Increase in fair value of net assets						$ 2,200.0
Enable Midstream Partners [Member]
Distributions from unconsolidated affiliates	$ 35.3	$ 35.3	$ 105.9	$ 105.9
OGE Holdings [Member]
Limited Liability Company or Limited Partnership, Members or Limited Partners, Ownership Interest	25.60%	25.70%	25.60%	25.70%