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This element represents the fair value of the noncontrolling interest in the acquiree at the acquisition date.

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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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Amount of tangible or intangible assets, including a business or subsidiary of the acquirer transferred by the entity to the former owners of the acquiree. Excludes cash.

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The amount of property, plant, and equipment recognized as of the acquisition date.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Data Type:	xbrli:monetaryItemType
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- References

No definition available.

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Data Type:	xbrli:stringItemType
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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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Acquisition purchase price

No definition available.

Name:	wec_Acquisitionpurchaseprice
Namespace Prefix:	wec_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

The capacity, in megawatts, of a generation unit.

No definition available.

Name:	wec_CapacityOfGenerationUnit
Namespace Prefix:	wec_
Data Type:	num:powerItemType
Balance Type:	na
Period Type:	instant

Duration of receiving tax benefits

No definition available.

Name:	wec_DurationOfReceivingTaxBenefits
Namespace Prefix:	wec_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

Duration of offtake agreement for the sale of energy produced

No definition available.

Name:	wec_Durationofofftakeagreementforthesaleofenergyproduced
Namespace Prefix:	wec_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

Represents the ownership interest of the generating facility acquired

No definition available.

Name:	wec_OwnershipInterestOfGeneratingFacilityAcquired
Namespace Prefix:	wec_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

Percent of tax benefits entitled to

No definition available.