Condensed Parent Company Financial Statements (Details 3) (USD $) In Millions, unless otherwise specified	Dec. 31, 2013
Parent Company long-term debt outstanding
Next year	$ 322.4
Year 2	399.5
Year 3	27.4
Year 4	29.5
Year 5	281.1
Thereafter	3,566.8
Total	4,626.7
Wisconsin Energy Corporation [Member]
Parent Company long-term debt outstanding
Next year	0
Year 2	0
Year 3	0
Year 4	0
Year 5	0
Thereafter	700.0
Total	$ 700.0

Face (par) amount of debt instrument at time of issuance.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

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Reference 2: http://www.xbrl.org/2003/role/presentationRef

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

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-Name Accounting Standards Codification

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