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Equity Investments (Tables) | 12 Months Ended
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Dec. 31, 2021
ATC [Member] |
Equity Investments [Line Items] |
Equity Investments [Table Text Block] |
ALLETE’s Investment in ATC |  |
Year Ended December 31 | 2021 | 2020
Millions |  |
Equity Investment Beginning Balance | $149.0 |  | $141.6 |
Cash Investments | — |  | 2.7 |
Equity in ATC Earnings | 21.3 |  | 22.3 |
Distributed ATC Earnings | (17.2) |  | (18.9) |
Amortization of the Remeasurement of Deferred Income Taxes | 1.4 |  | 1.3 |
Equity Investment Ending Balance | $154.5 |  | $149.0 |
ATC Summarized Financial Data |  |
Balance Sheet Data |  |
As of December 31 | 2021 | 2020
Millions |  |
Current Assets | $89.8 |  | $92.8 |
Non-Current Assets | 5,628.1 |  | 5,400.5 |
Total Assets | $5,717.9 |  | $5,493.3 |
Current Liabilities | $436.9 |  | $310.8 |
Long-Term Debt | 2,513.0 |  | 2,512.2 |
Other Non-Current Liabilities | 422.0 |  | 378.2 |
Members’ Equity | 2,346.0 |  | 2,292.1 |
Total Liabilities and Members’ Equity | $5,717.9 |  | $5,493.3 |
Income Statement Data |  |  |
Year Ended December 31 | 2021 | 2020 | 2019
Millions |  |  |
Revenue | $754.8 |  | $758.1 |  | $744.4 |
Operating Expense | 376.2 |  | 372.4 |  | 373.5 |
Other Expense | 113.9 |  | 110.9 |  | 110.5 |
Net Income | $264.7 |  | $274.8 |  | $260.4 |
ALLETE’s Equity in Net Income | $21.3 |  | $22.3 |  | $21.7 |
Nobles 2 [Member] |
Equity Investments [Line Items] |
Equity Investments [Table Text Block] |
ALLETE’s Investment in Nobles 2 |  |
Millions |  |
Equity Investment Balance as of December 31, 2020 | $152.2 |  |
Cash Investments | 17.6 |
Equity in Nobles 2 Earnings (a) | (1.3) |  |
Distributed Nobles 2 Earnings | (5.0) |  |
Equity Investment Balance as of December 31, 2021 | $163.5 |  |
(a)The Company also recorded net loss attributable to non-controlling interest of $6.6 million related to its investment in Nobles 2

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- Definition Tabular disclosure of equity method investments including, but not limited to, name of each investee or group of investments, percentage ownership, difference between recorded amount of an investment and the value of the underlying equity in the net assets, and summarized financial information. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=114001798&loc=d3e33918-111571 + Details
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