XML 40 R29.htm IDEA: XBRL DOCUMENT
v2.4.1.9

Goodwill and Intangible Assets (Tables) | 3 Months Ended
--- | ---
Mar. 31, 2015
Goodwill and Intangible Assets [Abstract] |
Schedule of Goodwill [Table Text Block] | The following table summarizes changes to goodwill by business segment for the three months ended March 31, 2015:
| Investments and Other |
Millions |
Balance as of December 31, 2014 |  | $2.9 |
Acquired Goodwill | 127.1 |
Balance as of March 31, 2015 |  | $130.0 |
Schedule of Intangible Assets [Table Text Block] | Balances of intangible assets, net, excluding goodwill as of March 31, 2015 are as follows:
| December 31, 2014 |  |  | Additions as a Result of Acquisitions |  | Amortization |  | March 31, 2015 |
Millions |  |  |  |  |  |  |
Intangible Assets |  |  |  |  |  |  |
Definite-Lived Intangible Assets |  |  |  |  |  |  |
Customer Relationships | — |  |  |  | $60.1 |  |  | $0.5 |  |  | $59.6 |
Developed Technology and Other (a) |  | $1.9 |  |  | 6.3 |  |  | 0.1 |  |  | 8.1 |
Total Definite-Lived Intangible Assets | 1.9 |  |  | 66.4 |  |  | 0.6 |  |  | 67.7 |
Indefinite-Lived Intangible Assets |  |  |  |  |  |  |
Trademarks and Trade Names | — |  |  | 16.6 |  |  | n/a |  |  | 16.6 |
Total Intangible Assets |  | $1.9 |  |  |  | $83.0 |  |  | $0.6 |  |  | $84.3 |
(a) | Developed Technology and Other includes patents, non-compete agreements, and land easements.

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

X
- Definition Tabular disclosure or assets, excluding financial assets and goodwill, lacking physical substance, by either major class or business segment. + References No definition available. + Details
Name: | ale_ScheduleofIntangibleAssetsTableTextBlock
Namespace Prefix: | ale_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tabular disclosure of goodwill by reportable segment and in total which includes a rollforward schedule. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13854-109267 + Details
Name: | us-gaap_ScheduleOfGoodwillTextBlock
Namespace Prefix: | us-gaap_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration