Represents the contracted capacity (in megawatts) from a variable interest entity under a power purchase agreement.

No definition available.

Name:	teg_ContractedCapacityfromVariableInterestEntity
Namespace Prefix:	teg_
Data Type:	num:powerItemType
Balance Type:	na
Period Type:	instant

- Definition

Represents the cash paid for the early termination of an existing contract.

+ References

No definition available.

+ Details

Name:	teg_ContractTerminationCosts
Namespace Prefix:	teg_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Represents the obligations to purchase energy (in megawatts) from a variable interest entity under a power purchase agreement.

+ References

No definition available.

+ Details

Name:	teg_ObligationsToPurchaseEnergyUnderPowerPurchaseAgreement
Namespace Prefix:	teg_
Data Type:	num:powerItemType
Balance Type:	na
Period Type:	duration

- Definition

The additional percentage ownership of a variable interest entity which was acquired by the entity during the period.

+ References

No definition available.

+ Details

Name:	teg_VariableInterestEntityRemainingPercentageOwnershipAcquired
Namespace Prefix:	teg_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_VariableInterestEntityLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

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

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 810

-SubTopic 10

-Section 50

-Paragraph 5A

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=7880789&loc=SL6759159-111685

+ Details

Name:	us-gaap_VariableInterestEntityOwnershipPercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

VARIABLE INTEREST ENTITIES (Details) (USD $) In Millions, unless otherwise specified		9 Months Ended			12 Months Ended	1 Months Ended	12 Months Ended
	Mar. 31, 2013 WPS Fox Energy Company LLC MW	Sep. 30, 2013 UPPCO MW	Sep. 30, 2013 AMP Trillium LLC Other Venturer's Ownership	Sep. 30, 2013 AMP Trillium LLC ITF	Dec. 31, 2011 PTI CNG Fuels LLC Other Venturer's Ownership	Jun. 30, 2013 PTI CNG Fuels LLC ITF	Dec. 31, 2011 PTI CNG Fuels LLC ITF
Variable Interest Entity
Contract termination fee related to tolling arrangement	$ 50.0
Contracted capacity under a power purchase agreement (in megawatts)	500	17.5
Obligations to purchase energy under power purchase agreement (in megawatts)		0
Variable interest entity ownership interest acquired (as a percent)			70.00%	30.00%	50.00%		50.00%
Remaining percentage ownership interest acquired (as a percent)						50.00%