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Represents the seller-financed note receivable included in the proceeds from the sale of a disposal group.

No definition available.

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For a disposal group, the amount of intercompany payables that were eliminated in consolidation, but will be included in the sale.

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

The estimated gain (loss) related to the future sale of a disposal group that is not a discontinued operation.

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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Represents the period during which Integrys Energy Group will continue to hold guarantees supporting the retail energy business of Integrys Energy Services. The buyer is obligated under the purchase agreement to replace these guarantees with its own credit support.

No definition available.

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Period Type:	duration

Represents the number of compressed natural gas fueling stations sold by Integrys Transportation Fuels, LLC to AMP Trillium, LLC.

No definition available.

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Period Type:	instant

Represents the number of compressed natural gas fueling stations under construction.

No definition available.

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Represents the period for which transition services are provided, following the sale of business.

No definition available.

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Proceeds received from the sale of a disposal group, net of tax.

No definition available.

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Data Type:	xbrli:monetaryItemType
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Represents the term of seller-financed note receivable.

No definition available.

Name:	teg_TermOfSellerFinancedNoteReceivable
Namespace Prefix:	teg_
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Amount of direct costs of the sale of the business including legal, accounting, and other costs incurred to sell the business.

No definition available.

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Balance Type:	debit
Period Type:	duration

Amount classified as assets attributable to disposal group held for sale or disposed of.

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Amount classified as assets attributable to disposal group held for sale or disposed of, expected to be disposed of within one year or the normal operating cycle, if longer.

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Amount of consideration received or receivable for the disposal of assets and liabilities, including discontinued operation.

No definition available.

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Amount classified as other assets attributable to disposal group held for sale or disposed of, expected to be disposed of after one year or the normal operating cycle, if longer.

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Amount classified as property, plant and equipment attributable to disposal group held for sale or disposed of, expected to be disposed of after one year or the normal operating cycle, if longer.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

-SubTopic 20

-Section 45

-Paragraph 10

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The gain (loss) resulting from the sale of a disposal group that is not a discontinued operation. It is included in income from continuing operations before income taxes in the income statement.

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

-Publisher FASB

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Amount classified as liabilities attributable to disposal group held for sale or disposed of.

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Amount classified as liabilities attributable to disposal group held for sale or disposed of, expected to be disposed of within one year or the normal operating cycle, if longer.

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Amount classified as liabilities attributable to disposal group held for sale or disposed of, expected to be disposed of beyond one year or the normal operating cycle, if longer.

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The cash outflow associated with the acquisition of or advances to an entity that is related to it but not strictly controlled (for example, an unconsolidated subsidiary, affiliate, and joint venture or equity method investment) or the acquisition of an additional interest in a subsidiary (controlled entity).

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

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The cash inflow associated with the amount received from the sale of a portion of the company's business, for example a segment, division, branch or other business, during the period.

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Investing Activities

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The cash inflow from the amounts received by the insured under the terms of an insurance contract settlement. This element pertains only to insurance proceeds related to investments, for example fixed assets. It excludes insurance settlements classified as operating cash flows.

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Percentage of the Variable Interest Entity's (VIE) voting interest owned by (or beneficial interest in) the reporting entity (directly or indirectly).

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 810

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-Subparagraph (d)

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