XML 115 R102.htm IDEA: XBRL DOCUMENT
v3.19.3

COMMITMENTS AND CONTINGENCIES - ENVIRONMENTAL MATTERS (Details) $ in Millions | 1 Months Ended | 9 Months Ended
--- | --- | ---
Apr. 30, 2019 degreecelsius | Dec. 31, 2018 USD ($) change | Sep. 30, 2019 USD ($) generating_units MW
Manufactured gas plant remediation |  |  |
Regulatory assets |  | $ 3,855.8 | $ 4,036.2
Environmental remediation costs |  |  |
Manufactured gas plant remediation |  |  |
Regulatory assets |  | $ 687.1 | $ 719.6
Mercury and Air Toxics Standards | Electric |  |  |
Air quality |  |  |
Revisions to Mercury and Air Toxics Standards | change |  | 0 |
Climate Change | Electric |  |  |
Air quality |  |  |
Company goal for percentage of carbon dioxide emissions reduction by 2030 |  |  | 40.00%
Long-term company goal for percentage of carbon dioxide emissions reduction by 2050 |  |  | 80.00%
Capacity of coal generation retired, in megawatts | MW |  |  | 1,800
Climate Change | Electric | Maximum |  |  |
Air quality |  |  |
Global temperature increases limit | degreecelsius | 2 |  |
Steam Electric Effluent Limitation Guidelines | Electric |  |  |
Water quality |  |  |
Number of generating units of OCPP and ERGS | generating_units |  |  | 6
Expected cost to achieve required emissions reductions |  |  | $ 70.0
Manufactured Gas Plant Remediation | Natural gas |  |  |
Manufactured gas plant remediation |  |  |
Reserves for future environmental remediation |  | $ 616.4 | 631.8
Manufactured Gas Plant Remediation | Natural gas | Environmental remediation costs |  |  |
Manufactured gas plant remediation |  |  |
Regulatory assets |  | $ 687.1 | $ 719.6

X
- Definition Total costs accrued as of the balance sheet date for environmental loss contingencies. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=118942415&loc=d3e14326-108349 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -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 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -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 + Details
Name: | us-gaap_AccrualForEnvironmentalLossContingencies
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- References No definition available. + Details
Name: | us-gaap_EnvironmentalRemediationObligationsAbstract
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 capacity, in megawatts, of coal generation retired + References No definition available. + Details
Name: | wec_CoalGenerationCapacityRetired
Namespace Prefix: | wec_
Data Type: | num:powerItemType
Balance Type: | na
Period Type: | duration

X
- Definition The percentage by which the company plans to reduce carbon dioxide emissions below 2005 levels by 2050 + References No definition available. + Details
Name: | wec_Companygoalforpercentageofcarbondioxideemissionsreductionby2050
Namespace Prefix: | wec_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition The capital and operating costs needed to achieve the required level of reduction in emissions. + References No definition available. + Details
Name: | wec_EnvironmentalCapitalAndOperatingCosts
Namespace Prefix: | wec_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition -- None. No documentation exists for this element. -- + References No definition available. + Details
Name: | wec_EnvironmentalComplianceObligationsAirQualityAbstract
Namespace Prefix: | wec_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition -- None. No documentation exists for this element. -- + References No definition available. + Details
Name: | wec_EnvironmentalComplianceObligationsWaterQualityAbstract
Namespace Prefix: | wec_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Global temperature increases limit + References No definition available. + Details
Name: | wec_Globaltemperatureincreaseslimit
Namespace Prefix: | wec_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition The percentage by which the company plans to reduce carbon dioxide emissions below 2005 levels by 2030. + References No definition available. + Details
Name: | wec_PercentageCarbonDioxideEmissionReductionCompanyGoal
Namespace Prefix: | wec_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Represents the number of revisions to Mercury and Air Toxics Standards + References No definition available. + Details
Name: | wec_RevisionstoMercuryandAirToxicsStandards
Namespace Prefix: | wec_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Total units of OCPP and ERGS + References No definition available. + Details
Name: | wec_TotalunitsofOCPPandERGS
Namespace Prefix: | wec_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Details
Name: | us-gaap_RegulatoryAssetAxis=us-gaap_EnvironmentalRestorationCostsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LossContingenciesByNatureOfContingencyAxis=wec_MercuryandAirToxicsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_ProductOrServiceAxis=us-gaap_ElectricityUsRegulatedMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LossContingenciesByNatureOfContingencyAxis=wec_ClimateChangeMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_MaximumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LossContingenciesByNatureOfContingencyAxis=wec_SteamElectricEffluentGuidelinesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LossContingenciesByNatureOfContingencyAxis=wec_ManufacturedGasPlantRemediationMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_ProductOrServiceAxis=us-gaap_NaturalGasUsRegulatedMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |