Name:	teg_EnvironmentalComplianceObligationsAbstract
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Represents the amount of beneficial environmental projects as agreed by the entity to settle a legal matter.

No definition available.

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Number of compliance options available to meet impingement mortality standard of the Clean Water Act rule under Section 316(b).

No definition available.

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Represents the percentage of mercury emission reduction required by the State of Wisconsin's mercury rule.

No definition available.

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Represents the amount of the expected recovery of deferred expenditures and estimated future expenditures, net of insurance recoveries, for remediation which the entity has recorded as regulatory assets.

No definition available.

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Represents a regulatory asset for the undepreciated book value of plants retired early in accordance with a Consent Decree.

No definition available.

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Total costs accrued as of the balance sheet date for environmental loss contingencies.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14326-108349

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 410

-SubTopic 30

-Section 50

-Paragraph 7

-URI http://asc.fasb.org/extlink&oid=6393242&loc=d3e13207-110859

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 25

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6395460&loc=d3e13647-108346

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- References

No definition available.

Name:	us-gaap_EnvironmentalRemediationObligationsAbstract
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- References

No definition available.

Name:	us-gaap_LossContingencyInformationAboutLitigationMattersAbstract
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The amount of loss pertaining to the specified contingency that was charged against earnings in the period, including the effects of revisions in previously reported estimates.

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Data Type:	xbrli:monetaryItemType
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Data Type:	na
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Data Type:	na
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