XML 41 R25.htm IDEA: XBRL DOCUMENT
v2.4.0.6

Schedule II | 12 Months Ended
--- | ---
Dec. 31, 2011
Schedule II [Abstract] |
Valuation and Qualifying Accounts and Reserves [Text Block] | Schedule II ALLETE Valuation and Qualifying Accounts and Reserves
| Balance at Beginning of Period |  | Additions Charged Other to Income Charges | Deductions from Reserves (a) | Balance at End of Period
Millions |  |  |  |  |  |
Reserve Deducted from Related Assets |  |  |  |  |  |
Reserve For Uncollectible Accounts |  |  |  |  |  |
2009 Trade Accounts Receivable |  | $0.7 |  |  |  | $1.3 |  | — |  |  | $1.1 |  |  | $0.9 |
Finance Receivables – Long-Term |  | $0.1 |  |  |  | $0.3 |  | — |  | — |  |  | $0.4 |
2010 Trade Accounts Receivable |  | $0.9 |  |  |  | $1.1 |  | — |  |  | $1.1 |  |  | $0.9 |
Finance Receivables – Long-Term |  | $0.4 |  |  |  | $0.8 |  | — |  |  | $0.4 |  |  | $0.8 |
2011 Trade Accounts Receivable |  | $0.9 |  |  |  | $1.3 |  | — |  |  | $1.3 |  |  | $0.9 |
Finance Receivables – Long-Term |  | $0.8 |  |  |  | $0.1 |  | — |  |  | $0.3 |  |  | $0.6 |
Deferred Asset Valuation Allowance |  |  |  |  |  |
2009 Deferred Tax Assets |  | $0.4 |  |  | $(0.1) | — |  | — |  |  | $0.3 |
2010 Deferred Tax Assets |  | $0.3 |  |  |  | $0.2 |  | — |  | — |  |  | $0.5 |
2011 Deferred Tax Assets |  | $0.5 |  |  | $(0.1) | — |  | — |  |  | $0.4 |
(a) | Includes uncollectible accounts written off.

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

X
- Definition The entire disclosure for any allowance and reserve accounts (their beginning and ending balances, as well as a reconciliation by type of activity during the period). Alternatively, disclosure of the required information may be within the footnotes to the financial statements or a supplemental schedule to the financial statements. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 09 -Article 12 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=6881521&loc=d3e24092-122690 + Details
Name: | us-gaap_ScheduleOfValuationAndQualifyingAccountsDisclosureTextBlock
Namespace Prefix: | us-gaap_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration