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v3.23.1

Revenue Recognition Revenue Recognition (Allowance for Credit Losses) (Details) - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Mar. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Accounts Receivable Allowance For Credit Loss [Line Items] |  |  |
Accounts Receivable, Allowance for Credit Loss | $ 31.4 | $ 23.9 | $ 23.5
Current period provisions | 12.4 | 36.0 |
Write-offs charged against allowance | 13.6 | 57.4 |
Recoveries of amounts previously written off | 8.7 | 21.8 |
Gas Distribution Operations |  |  |
Accounts Receivable Allowance For Credit Loss [Line Items] |  |  |
Accounts Receivable, Allowance for Credit Loss | 24.0 | 17.2 | 18.9
Current period provisions | 10.4 | 29.1 |
Write-offs charged against allowance | 12.1 | 52.1 |
Recoveries of amounts previously written off | 8.5 | 21.3 |
Electric Operations |  |  |
Accounts Receivable Allowance For Credit Loss [Line Items] |  |  |
Accounts Receivable, Allowance for Credit Loss | 6.6 | 5.9 | 3.8
Current period provisions | 2.0 | 6.9 |
Write-offs charged against allowance | 1.5 | 5.3 |
Recoveries of amounts previously written off | 0.2 | 0.5 |
Corporate and Other |  |  |
Accounts Receivable Allowance For Credit Loss [Line Items] |  |  |
Accounts Receivable, Allowance for Credit Loss | 0.8 | 0.8 | $ 0.8
Current period provisions | 0.0 | 0.0 |
Write-offs charged against allowance | 0.0 | 0.0 |
Recoveries of amounts previously written off | $ 0.0 | $ 0.0 |

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