XML 78 R66.htm IDEA: XBRL DOCUMENT
v3.25.3

CREDIT LOSSES - ROLLFORWARD OF ALLOWANCES (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2024
Accounts Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |
Balance at beginning of period | $ 142.2 | $ 166.9 | $ 162.8 | $ 193.5
Provision for credit losses | 32.8 | 23.8 | 100.8 | 73.4
Write-offs charged against the allowance | (52.9) | (46.2) | (167.8) | (170.4)
Recoveries of amounts previously written off | 33.5 | 17.7 | 87.1 | 54.8
Balance at end of period | 129.5 | 155.0 | 129.5 | 155.0
Change in allowance for credit losses |  |  | 33.3 | 38.5
Uncollectible expense |  |  |  |
Accounts Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |
Provision for credit losses deferred for future recovery or refund | (26.1) | (7.2) | (53.4) | 3.7
Public Utilities |  |  |  |
Accounts Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |
Balance at beginning of period |  |  | 162.8 |
Balance at end of period | 129.5 |  | 129.5 |
Wisconsin | Public Utilities |  |  |  |
Accounts Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |
Balance at beginning of period | 52.3 | 68.7 | 73.6 | 77.4
Provision for credit losses | 21.8 | 12.6 | 59.6 | 36.2
Write-offs charged against the allowance | (35.7) | (30.8) | (108.0) | (102.3)
Recoveries of amounts previously written off | 11.3 | 9.6 | 37.5 | 31.7
Balance at end of period | 48.7 | 63.9 | 48.7 | 63.9
Wisconsin | Public Utilities | Uncollectible expense |  |  |  |
Accounts Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |
Provision for credit losses deferred for future recovery or refund | (1.0) | 3.8 | (14.0) | 20.9
Illinois | Public Utilities |  |  |  |
Accounts Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |
Balance at beginning of period | 84.6 | 93.2 | 83.9 | 109.7
Provision for credit losses | 11.6 | 11.5 | 41.3 | 38.8
Write-offs charged against the allowance | (12.2) | (12.9) | (53.5) | (63.2)
Recoveries of amounts previously written off | 17.7 | 6.1 | 44.3 | 18.8
Balance at end of period | 76.6 | 86.9 | 76.6 | 86.9
Illinois | Public Utilities | Uncollectible expense |  |  |  |
Accounts Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |
Provision for credit losses deferred for future recovery or refund | (25.1) | (11.0) | (39.4) | (17.2)
Other States | Public Utilities |  |  |  |
Accounts Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |
Balance at beginning of period | 5.3 | 5.0 | 5.3 | 6.4
Provision for credit losses | (0.6) | (0.3) | (0.1) | (1.6)
Write-offs charged against the allowance | (5.0) | (2.5) | (6.3) | (4.9)
Recoveries of amounts previously written off | 4.5 | 2.0 | 5.3 | 4.3
Balance at end of period | 4.2 | 4.2 | 4.2 | 4.2
Other States | Public Utilities | Uncollectible expense |  |  |  |
Accounts Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |
Provision for credit losses deferred for future recovery or refund | $ 0.0 | $ 0.0 | $ 0.0 | $ 0.0

X
- Definition Amount of allowance for credit loss on accounts receivable. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 13 -Subparagraph (f) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479319/326-20-50-13 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 13 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479319/326-20-50-13 Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 944 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(5)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478777/944-210-S99-1 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(4)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479344/326-20-45-1 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Topic 310 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 4 -Publisher FASB -URI https://asc.fasb.org/1943274/2147481962/310-10-50-4 + Details
Name: | us-gaap_AllowanceForDoubtfulAccountsReceivable
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of increase (decrease) in allowance for credit loss on accounts receivable. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 13 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479319/326-20-50-13 + Details
Name: | us-gaap_AllowanceForDoubtfulAccountsReceivablePeriodIncreaseDecrease
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of increase in allowance for credit loss on accounts receivable, from recovery. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 13 -Subparagraph (e) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479319/326-20-50-13 + Details
Name: | us-gaap_AllowanceForDoubtfulAccountsReceivableRecoveries
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
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_AllowanceForDoubtfulAccountsReceivableRollforward
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of direct write-downs of accounts receivable charged against the allowance. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 13 -Subparagraph (d) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479319/326-20-50-13 + Details
Name: | us-gaap_AllowanceForDoubtfulAccountsReceivableWriteOffs
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The increase (decrease) during the reporting period in the value of assets that are created when regulatory agencies permits public utilities to defer costs (revenues) to the balance sheet. This element is a the increase (decrease) of regulatory assets and liabilities combined. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 45 -Paragraph 28 -Subparagraph (a) -SubTopic 10 -Topic 230 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482740/230-10-45-28 + Details
Name: | us-gaap_IncreaseDecreaseInRegulatoryAssetsAndLiabilities
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of expense (reversal of expense) for expected credit loss on accounts receivable. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 13 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479319/326-20-50-13 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 220 -SubTopic 40 -Name Accounting Standards Codification -Section 50 -Paragraph 22 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147476148/220-40-50-22 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 220 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03(5)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147483621/220-10-S99-2 + Details
Name: | us-gaap_ProvisionForDoubtfulAccounts
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

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

X
- Details
Name: | srt_ProductOrServiceAxis=us-gaap_PublicUtilitiesMember
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: |

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

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