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v3.19.1

Regulatory Matters (Tables) | 3 Months Ended
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Mar. 31, 2019
Regulated Operations [Abstract] |
Regulatory Assets and Liabilities [Table Text Block] |
Regulatory Assets and Liabilities | March 31, 2019 |  |  | December 31, 2018 |
Millions |  |  |
Non-Current Regulatory Assets |  |  |
Defined Benefit Pension and Other Postretirement Benefit Plans |  | $218.0 |  |  |  | $218.5 |
Income Taxes | 103.2 |  |  | 105.5 |
Asset Retirement Obligations | 32.4 |  |  | 32.6 |
Boswell 1 and 2 Net Plant and Equipment | 14.8 |  |  | 16.3 |
Manufactured Gas Plant | 8.1 |  |  | 8.0 |
PPACA Income Tax Deferral | 4.9 |  |  | 5.0 |
Other | 3.7 |  |  | 3.6 |
Total Non-Current Regulatory Assets |  | $385.1 |  |  |  | $389.5 |
Current Regulatory Liabilities (a) |  |  |
Provision for Interim Rate Refund (b) |  | $40.6 |  |  |  | $40.0 |
Transmission Formula Rates Refund | 3.3 |  |  | 4.4 |
Provision for Tax Reform Refund (c) | 0.5 |  |  | 10.7 |
Total Current Regulatory Liabilities | 44.4 |  |  | 55.1 |
Non-Current Regulatory Liabilities |  |  |
Income Taxes | 389.4 |  |  | 396.4 |
Wholesale and Retail Contra AFUDC | 67.3 |  |  | 64.4 |
Plant Removal Obligations | 26.8 |  |  | 25.1 |
North Dakota Investment Tax Credits | 12.3 |  |  | 14.7 |
Conservation Improvement Program | 5.2 |  |  | 1.5 |
Transmission Formula Rates Refund | 1.6 |  |  | 1.6 |
Cost Recovery Riders | — |  |  | 6.9 |
Other | 1.5 |  |  | 1.5 |
Total Non-Current Regulatory Liabilities | 504.1 |  |  | 512.1 |
Total Regulatory Liabilities |  | $548.5 |  |  |  | $567.2 |
(a) | Current regulatory liabilities are presented within Other Current Liabilities on the Consolidated Balance Sheet.
(b) | This amount is expected to be refunded to Minnesota Power’s regulated retail customers in the second quarter of 2019.
(c) Provision for Tax Reform Refund related to the income tax benefits of the TCJA in 2018 was refunded to Minnesota Power customers in the first quarter of 2019 and will be refunded to SWL&P customers in 2019 and 2020.

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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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