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v3.21.1

Regulatory Matters (Tables) | 3 Months Ended
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Mar. 31, 2021
Regulated Operations [Abstract] |
Regulatory Assets and Liabilities [Table Text Block] |
Regulatory Assets and Liabilities | March 31, 2021 |  | December 31, 2020
Millions |  |  |
Non-Current Regulatory Assets |  |  |
Defined Benefit Pension and Other Postretirement Benefit Plans | $255.3 |  |  | $259.7 |
Income Taxes | 110.7 |  |  | 113.7 |
Cost Recovery Riders | 57.5 |  |  | 54.0 |
Asset Retirement Obligations | 31.5 |  |  | 31.6 |
Manufactured Gas Plant | 5.8 |  |  | 8.8 |
Boswell Units 1 and 2 Net Plant and Equipment | 3.6 |  |  | 5.0 |
PPACA Income Tax Deferral | 4.5 |  |  | 4.5 |
Other | 3.8 |  |  | 3.6 |
Total Non-Current Regulatory Assets | $472.7 |  |  | $480.9 |
Current Regulatory Liabilities (a) |  |  |
Fuel Adjustment Clause | $1.8 |  |  | $3.7 |
Transmission Formula Rates Refund | 2.4 |  |  | 2.9 |
Other | 0.4 |  |  | 1.0 |
Total Current Regulatory Liabilities | 4.6 |  |  | 7.6 |
Non-Current Regulatory Liabilities |  |  |
Income Taxes | 367.8 |  |  | 375.3 |
Wholesale and Retail Contra AFUDC | 85.9 |  |  | 86.6 |
Plant Removal Obligations | 43.0 |  |  | 41.2 |
Defined Benefit Pension and Other Postretirement Benefit Plans | 3.4 |  |  | 4.4 |
North Dakota Investment Tax Credits | 12.4 |  |  | 12.0 |
Conservation Improvement Program | 1.7 |  |  | 1.5 |
Other | 3.7 |  |  | 3.8 |
Total Non-Current Regulatory Liabilities | 517.9 |  |  | 524.8 |
Total Regulatory Liabilities | $522.5 |  |  | $532.4 |
(a)Current regulatory liabilities are presented within Other Current Liabilities on the Consolidated Balance Sheet.

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- Definition The entire disclosure for detailed information about regulatory assets and liabilities, including current and noncurrent assets created when regulatory agencies permit the deferral of costs to the balance sheet that would otherwise be required to appear on the company's income statement and would be charged against current expenses or revenues, as well as current and noncurrent liabilities created when regulatory agencies permit. + References No definition available. + Details
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