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v3.22.2.2

Operations and Significant Accounting Policies - Other Income (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2022 | Sep. 30, 2021 | Sep. 30, 2022 | Sep. 30, 2021
Other Income (Expense) - Other [Line Items] |  |  |  |  |  |
Total Other Income |  | $ 2.3 | $ 1.0 | $ 16.4 |  | $ 6.1
Pension and Other Postretirement Benefit Plans Non-Service Credit [Member] |  |  |  |  |  |
Other Income (Expense) - Other [Line Items] |  |  |  |  |  |
Total Other Income | [1] | 1.9 | 1.6 | 7.2 |  | 4.4
Interest and Investment Income (Loss) [Member] |  |  |  |  |  |
Other Income (Expense) - Other [Line Items] |  |  |  |  |  |
Total Other Income |  | (0.4) | (0.1) | (1.3) |  | 1.7
AFUDC - Equity [Member] |  |  |  |  |  |
Other Income (Expense) - Other [Line Items] |  |  |  |  |  |
Total Other Income |  | 0.7 | 0.6 | 2.4 |  | 1.7
PSA Liability [Member] |  |  |  |  |  |
Other Income (Expense) - Other [Line Items] |  |  |  |  |  |
Total Other Income |  | 0.0 | 0.0 | 10.2 | [2] | 0.0
Other [Member] |  |  |  |  |  |
Other Income (Expense) - Other [Line Items] |  |  |  |  |  |
Total Other Income |  | $ 0.1 | $ (1.1) | $ (2.1) |  | $ (1.7)
[1] | These are components of net periodic pension and other postretirement benefit cost other than service cost. (See Note 10. Pension and Other Postretirement Benefit Plans.)
[2] | The gain on removal of the PSA liability for the Northern Wind project upon decommissioning of the legacy wind energy facility assets, which was fully offset by a reserve for an anticipated loss on the sale of the Northern Wind project.

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- Definition [Line Items] for Other Income (Expense) - Other [Table] + References No definition available. + Details
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- Definition Amount of income (expense) related to nonoperating activities, classified as other. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.9) -URI https://asc.fasb.org/extlink&oid=126953954&loc=SL114868664-224227 + Details
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