Acquisition Approval Conditions (Details)	1 Months Ended
Jun. 30, 2015	Jun. 29, 2015
Acquisition
WEC interest in ATC	60.00%	60.00%
Wisconsin electric [Member]
Acquisition
Duration of earnings cap condition imposed by the PSCW	3 years
Wisconsin Gas [Member]
Acquisition
Duration of earnings cap condition imposed by the PSCW	3 years
PGL
Acquisition
Duration of rate base freeze condition imposed by the ICC	2 years
NSG
Acquisition
Duration of rate base freeze condition imposed by the ICC	2 years

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 323

-SubTopic 10

-Section 50

-Paragraph 3

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=6382943&loc=d3e33918-111571

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Duration of earnings cap condition imposed by the PSCW as a condition for the approval of the acquisition of Integrys

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Duration of rate base freeze condition imposed by the ICC for the approval of the acquisition of Integrys

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