Note 2 - Significant Accounting Policies and Methods of Application (Details) - Purchase Price Allocation (USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Business Acquisition [Line Items]
Goodwill	$ 1,827us-gaap_Goodwill	$ 1,827us-gaap_Goodwill
NiSource Inc. [Member]
Business Acquisition [Line Items]
Current assets		3
PP&E		12
Goodwill		51
Intangible assets		62
Current liabilities		(6)
Total purchase price		$ 122

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Amount of assets that are expected to be realized or consumed within one year or the normal operating cycle, if longer, acquired at the acquisition date.

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Amount of liabilities due within one year or within the normal operating cycle, if longer, assumed at the acquisition date.

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The amount of identifiable intangible assets recognized as of the acquisition date.

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-SubTopic 20

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The amount of property, plant, and equipment recognized as of the acquisition date.

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Amount recognized for assets, including goodwill, in excess of (less than) the aggregate liabilities assumed.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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