Investment in Unconsolidated Affiliates Summarized Income Statement of Equity Method Investment (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2014
Summarized Income Statement of Equity Method Investment [Abstract]
Operating revenues	$ 1,001.6
Cost of sales	632.6
Operating income	161.9
Net income attributable to Enable	$ 149.2

The amount of net income (loss) reported by an equity method investment of the entity.

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