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v3.20.2

Operations and Significant Accounting Policies (Details) - USD ($) $ in Millions | 6 Months Ended |  |
--- | --- | --- | ---
Jun. 30, 2020 | Jun. 30, 2019 | Dec. 31, 2019 | Dec. 31, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract] |  |  |  |  |
Recognition of Right-of-use Assets and Lease Liabilities |  | $ 0.0 | $ 31.2 |  |
Cash, Cash Equivalents and Restricted Cash [Abstract] |  |  |  |  |
Cash and Cash Equivalents |  | 25.7 | 203.1 | $ 69.3 | $ 69.1
Restricted Cash included in Prepayments and Other |  | 7.3 | 0.9 | 2.8 | 1.3
Restricted Cash, Non-Current |  | 4.4 | 2.6 | 20.4 | 8.6
Total Cash, Cash Equivalents and Restricted Cash |  | 37.4 | 206.6 | 92.5 | 79.0
Inventories – Net [Abstract] |  |  |  |  |
Fuel | [1] | 33.5 |  | 25.9 |
Materials and Supplies |  | 48.5 |  | 46.9 |
Total Inventories – Net |  | 82.0 |  | 72.8 |
Other Non-Current Assets [Abstract] |  |  |  |  |
Contract Assets | [2] | 26.7 |  | 28.0 |
Operating Lease, Right-of-Use Asset |  | 25.4 |  | 28.6 |
ALLETE Properties |  | 21.5 |  | 21.9 |
Restricted Cash, Non-Current |  | 4.4 | $ 2.6 | 20.4 | $ 8.6
Other Postretirement Benefit Plans |  | 38.4 |  | 37.5 |
Other |  | 84.7 |  | 81.8 |
Total Other Non-Current Assets |  | 201.1 |  | 218.2 |
Other Current Liabilites [Abstract] |  |  |  |  |
PSAs |  | 12.4 |  | 12.3 |
Provision for Interim Rate Refund | [3] | 11.7 |  | 0.0 |
Operating Lease Liabilities |  | 6.6 |  | 6.9 |
Other |  | 34.7 |  | 41.2 |
Total Other Current Liabilities |  | 65.4 |  | 60.4 |
Other Non-Current Liabilities [Abstract] |  |  |  |  |
Asset Retirement Obligation |  | 164.8 |  | 160.3 |
PSAs |  | 58.3 |  | 64.6 |
Operating Lease Liabilities |  | 18.8 |  | 21.8 |
Other |  | 46.2 |  | 46.3 |
Total Other Non-Current Liabilities |  | $ 288.1 |  | $ 293.0 |
[1] | Fuel consists primarily of coal inventory at Minnesota Power.
[2] | Contract Assets consist of payments made to customers as an incentive to execute or extend service agreements. The contract payments are being amortized over the term of the respective agreements as a reduction to revenue.
[3] | Provision for Interim Rate Refund represents reserves for interim rates resulting from the MPUC’s approval of Minnesota Power’s petition and proposal to resolve and withdraw its rate case. (See Note 2. Regulatory Matters.)

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