XML 79 R35.htm IDEA: XBRL DOCUMENT
v2.4.0.8

Investment in ATC (Tables) | 12 Months Ended
--- | ---
Dec. 31, 2013
Investment in ATC [Abstract] |
ALLETE's Interest in ATC [Table Text Block] |
ALLETE’s Investment in ATC |  |
Year Ended December 31 | 2013 |  | 2012 |
Millions |  |
Equity Investment Beginning Balance |  | $107.3 |  |  | $98.9 |
Cash Investments | 3.1 |  | 4.7 |
Equity in ATC Earnings | 20.3 |  | 19.4 |
Distributed ATC Earnings | (16.1 | ) | (15.7 | )
Equity Investment Ending Balance |  | $114.6 |  |  | $107.3 |
ATC Summarized Financial Data [Table Text Block] |
ATC Summarized Financial Data |  |
Balance Sheet Data |  |
As of December 31 | 2013 |  | 2012 |
Millions |  |
Current Assets |  | $80.7 |  |  | $63.1 |
Non-Current Assets | 3,509.5 |  | 3,274.7 |
Total Assets |  | $3,590.2 |  |  | $3,337.8 |
Current Liabilities |  | $381.4 |  |  | $251.5 |
Long-Term Debt | 1,550.0 |  | 1,550.0 |
Other Non-Current Liabilities | 126.2 |  | 95.8 |
Members’ Equity | 1,532.6 |  | 1,440.5 |
Total Liabilities and Members’ Equity |  | $3,590.2 |  |  | $3,337.8 |
Income Statement Data |  |  |
Year Ended December 31 | 2013 |  | 2012 |  | 2011 |
Millions |  |  |
Revenue |  | $626.3 |  |  | $603.2 |  |  | $567.2 |
Operating Expense | 295.1 |  | 281.0 |  | 261.6 |
Other Expense | 83.6 |  | 84.8 |  | 81.7 |
Net Income |  | $247.6 |  |  | $237.4 |  |  | $223.9 |
ALLETE’s Equity in Net Income |  | $20.3 |  |  | $19.4 |  |  | $18.4 |

X
- Definition Tabular disclosure of summarized financial data reported by an equity method investment of the entity. + References No definition available. + Details
Name: | ale_EquityMethodInvestmentScheduleOfSummarizedFinancialDataTableTextBlock
Namespace Prefix: | ale_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | ale_InvestmentInAtcAbstract
Namespace Prefix: | ale_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- 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://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6382943&loc=d3e33918-111571 + Details
Name: | us-gaap_EquityMethodInvestmentsTextBlock
Namespace Prefix: | us-gaap_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration