XML 77 R66.htm IDEA: XBRL DOCUMENT
v3.10.0.1

PROPERTY, PLANT, AND EQUIPMENT (Details) $ in Millions | 1 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Oct. 31, 2017 MW | Sep. 30, 2018 USD ($) | Dec. 31, 2017 USD ($)
Property, plant, and equipment |  |  |
Cost of removal reserve classified as a regulatory liability |  | $ 3,985.9 | $ 3,760.4
Net book value of plant classified as a regulatory asset |  | 3,673.8 | $ 2,840.4
Edgewater Unit 4 |  |  |
Property, plant, and equipment |  |  |
Plant to be retired, at carrying value |  | 8.3 |
Cost of removal reserve classified as a regulatory liability |  | 1.9 |
Net book value of plant classified as a regulatory asset |  | 10.2 |
Pleasant Prairie power plant |  |  |
Property, plant, and equipment |  |  |
Plant to be retired, at carrying value |  | 653.3 |
Cost of removal reserve classified as a regulatory liability |  | 102.5 |
Net book value of plant classified as a regulatory asset |  | 755.8 |
Presque Isle power plant |  |  |
Property, plant, and equipment |  |  |
Plant to be retired, at carrying value |  | 186.9 |
Cost of removal reserve classified as a regulatory liability |  | 10.5 |
Plant to be retired, net |  | 197.4 |
Pulliam power plant |  |  |
Property, plant, and equipment |  |  |
Plant to be retired, at carrying value |  | 40.8 |
Cost of removal reserve classified as a regulatory liability |  | 20.3 |
Plant to be retired, net |  | 61.1 |
UMERC |  |  |
Property, plant, and equipment |  |  |
Capacity of natural gas-fired generation facility (in megawatts) | MW | 180 |  |
Wisconsin |  |  |
Changes to severance liability |  |  |
Severance liability, balance at beginning of period |  | 29.4 |
Severance payments |  | (9.5) |
Other |  | (3.0) |
Severance liability, balance at end of period |  | $ 16.9 |

X
- Definition Amount of cash payments made as the result of exit or disposal activities. Excludes payments associated with a discontinued operation or an asset retirement obligation. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 420 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b)(2) -URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 17 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3367-108585 + Details
Name: | us-gaap_PaymentsForRestructuring
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
Name: | us-gaap_PropertyPlantAndEquipmentLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The amount for the individual regulatory asset as itemized in a table of regulatory assets as of the end of the period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 980 -SubTopic 340 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6499975&loc=d3e44250-110382 + Details
Name: | us-gaap_RegulatoryAssets
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition The amount for the individual regulatory liability as itemized in a table of regulatory liabilities as of the end of the period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 980 -SubTopic 405 -Section 25 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6500807&loc=d3e48068-110394 + Details
Name: | us-gaap_RegulatoryLiabilities
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 420 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b)(2) -URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 420 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SAB TOPIC 5.P.4(b)) -URI http://asc.fasb.org/extlink&oid=115931487&loc=d3e140904-122747 + Details
Name: | us-gaap_RestructuringReserve
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of expense (reversal of expense) which increases (decreases) the restructuring reserve from an adjustment to a previously accrued restructuring liability. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 420 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 420 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SAB TOPIC 5.P.4(b)(2)) -URI http://asc.fasb.org/extlink&oid=115931487&loc=d3e140904-122747 + Details
Name: | us-gaap_RestructuringReserveAccrualAdjustment1
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. + References No definition available. + Details
Name: | us-gaap_RestructuringReserveRollForward
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The capacity (in megawatts) of a natural gas-fired generation facility. + References No definition available. + Details
Name: | wec_CapacityOfNaturalGasFiredGenerationFacility
Namespace Prefix: | wec_
Data Type: | num:powerItemType
Balance Type: | na
Period Type: | duration

X
- Definition The amount of long-lived assets that will be abandoned, net of accumulated depreciation. + References No definition available. + Details
Name: | wec_LonglivedAssetsToBeAbandonedNet
Namespace Prefix: | wec_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition This is the value of Property, plant, and equipment, at carrying value which is made up of the net book value of the property, plant, and equipment less the cost of removal reserve. + References No definition available. + Details
Name: | wec_Propertyplantandequipmentatcarryingvalue
Namespace Prefix: | wec_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | us-gaap_JointlyOwnedUtilityPlantAxis=wec_EdgewaterUnit4Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=wec_PleasantPrairiePowerPlantMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=wec_PresqueIslePowerPlantPIPPMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PublicUtilityAxis=wec_PulliamPowerPlantMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | dei_LegalEntityAxis=wec_UpperMichiganEnergyResourcesCorporationMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementBusinessSegmentsAxis=wec_WisconsinMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |