v2.4.0.6

Leases (Schedule Of Lease Expenses Included In Consolidated Statements Of Income) (Details) (WPL [Member], Sheboygan Falls Energy Facility [Member], USD $) In Millions, unless otherwise specified | 12 Months Ended
--- | ---
Dec. 31, 2012 | Dec. 31, 2011 | Dec. 31, 2010
WPL [Member] | Sheboygan Falls Energy Facility [Member] |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Interest expense | $ 11.3 | $ 11.7 | $ 12.0
Depreciation and amortization | 6.2 | 6.2 | 6.2
Total lease expenses included in Consolidated Statements of Income | $ 17.5 | $ 17.9 | $ 18.2

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- Definition The charge for the use of long-lived depreciable capital leased assets for the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 30 -Section 45 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6455314&loc=d3e45031-112735 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 13 -Paragraph 13 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 980 -SubTopic 840 -Section 55 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6501752&loc=d3e56872-110439 + Details
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- Definition The financing charge for leasing arrangements meeting the criteria for capitalization. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 30 -Section 45 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6455314&loc=d3e45031-112735 + Details
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