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v3.23.3

Regulatory Matters (Tables) | 9 Months Ended
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Sep. 30, 2023
Regulated Operations [Abstract] |
Regulatory Assets and Liabilities | The recovery, refund or credit to rates for these regulatory assets and liabilities will occur over the periods either specified by the applicable regulatory authority or over the corresponding period related to the asset or liability. NOTE 2. REGULATORY MATTERS (Continued)
Regulatory Assets and Liabilities | September 30, 2023 |  | December 31, 2022 |  |
Millions |  |  |  |  |
Current Regulatory Assets (a) |  |  |  |  |
Fuel Adjustment Clause | $12.1 |  |  | $25.6 |  |  |
Other | 1.8 |  |  | — |  |  |
Total Current Regulatory Assets | $13.9 |  |  | $25.6 |  |  |
Non-Current Regulatory Assets |  |  |  |  |
Defined Benefit Pension and Other Postretirement Plans | $223.6 |  |  | $225.9 |  |  |
Income Taxes | 91.4 |  |  | 97.6 |  |  |
Cost Recovery Riders | 40.8 |  |  | 41.2 |  |  |
Asset Retirement Obligations | 37.1 |  |  | 35.6 |  |  |
Taconite Harbor (b) | 24.2 |  |  | — |  |  |
Manufactured Gas Plant | 14.1 |  |  | 15.1 |  |  |
Fuel Adjustment Clause | 4.1 |  |  | 14.5 |  |  |
PPACA Income Tax Deferral | 4.0 |  |  | 4.1 |  |  |
Other | 4.0 |  |  | 7.0 |  |  |
Total Non-Current Regulatory Assets | $443.3 |  |  | $441.0 |  |  |
Current Regulatory Liabilities (c) |  |  |  |  |
Provision for Interim Rate Refund (d) | $39.4 |  |  | $18.4 |  |  |
Transmission Formula Rates Refund | 1.2 |  |  | 4.9 |  |  |
Other | 1.3 |  |  | 0.1 |  |  |
Total Current Regulatory Liabilities | $41.9 |  |  | $23.4 |  |  |
Non-Current Regulatory Liabilities |  |  |  |  |
Income Taxes | $315.7 |  |  | $332.5 |  |  |
Wholesale and Retail Contra AFUDC | 78.6 |  |  | 80.7 |  |  |
Plant Removal Obligations | 65.9 |  |  | 60.0 |  |  |
Fuel Adjustment Clause | 28.3 |  |  | — |  |  |
Non-Jurisdictional Land Sales | 20.7 |  |  | 7.5 |  |  |
North Dakota Investment Tax Credits | 16.4 |  |  | 16.9 |  |  |
Defined Benefit Pension and Other Postretirement Benefit Plans | 11.8 |  |  | 17.6 |  |  |
Boswell Units 1 and 2 Net Plant and Equipment | 6.7 |  |  | 6.7 |  |  |
Other | 5.2 |  |  | 4.2 |  |  |
Total Non-Current Regulatory Liabilities | $549.3 |  |  | $526.1 |  |  |
(a)Current regulatory assets are presented within Prepayments and Other on the Consolidated Balance Sheet. (b)In the first quarter of 2023, Minnesota Power retired Taconite Harbor Units 1 and 2. The remaining net book value was reclassified from property, plant and equipment to a regulatory asset on the Consolidated Balance Sheet when the units were retired. Minnesota Power expects to receive recovery of the remaining net book value from customers. (c)Current regulatory liabilities are presented within Other Current Liabilities on the Consolidated Balance Sheet. (d)See 2022 Minnesota General Rate Case.

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