XML 104 R59.htm IDEA: XBRL DOCUMENT
v2.4.0.8

Regulatory Matters (Regulatory Liabilities) (Details) (USD $) In Millions, unless otherwise specified | Dec. 31, 2013 | Dec. 31, 2012
--- | --- | ---
Regulatory Liabilities [Line Items] |  |
Regulatory liabilities | $ 821.5 | $ 916.1
Cost of removal obligations [Member] |  |
Regulatory Liabilities [Line Items] |  |
Regulatory liabilities | 418.9 | 408.7
IPL's tax benefit riders [Member] |  |
Regulatory Liabilities [Line Items] |  |
Regulatory liabilities | 265.4 | 355.8
Energy conservation cost recovery [Member] |  |
Regulatory Liabilities [Line Items] |  |
Regulatory liabilities | 52.7 | 55.1
IPL's electric transmission assets sale [Member] |  |
Regulatory Liabilities [Line Items] |  |
Regulatory liabilities | 21.6 | 32.5
IPL's electric transmission cost recovery [Member] |  |
Regulatory Liabilities [Line Items] |  |
Regulatory liabilities | 14.6 | 0
Commodity cost recovery [Member] |  |
Regulatory Liabilities [Line Items] |  |
Regulatory liabilities | 7.5 | 17.7
Other [Member] |  |
Regulatory Liabilities [Line Items] |  |
Regulatory liabilities | 40.8 | 46.3
IPL [Member] |  |
Regulatory Liabilities [Line Items] |  |
Regulatory liabilities | 614.9 | 701.4
IPL [Member] | Cost of removal obligations [Member] |  |
Regulatory Liabilities [Line Items] |  |
Regulatory liabilities | 277.7 | 268.0
IPL [Member] | IPL's tax benefit riders [Member] |  |
Regulatory Liabilities [Line Items] |  |
Regulatory liabilities | 265.4 | 355.8
IPL [Member] | Energy conservation cost recovery [Member] |  |
Regulatory Liabilities [Line Items] |  |
Regulatory liabilities | 9.3 | 10.0
IPL [Member] | IPL's electric transmission assets sale [Member] |  |
Regulatory Liabilities [Line Items] |  |
Regulatory liabilities | 21.6 | 32.5
IPL [Member] | IPL's electric transmission cost recovery [Member] |  |
Regulatory Liabilities [Line Items] |  |
Regulatory liabilities | 14.6 | 0
IPL [Member] | Commodity cost recovery [Member] |  |
Regulatory Liabilities [Line Items] |  |
Regulatory liabilities | 5.5 | 5.2
IPL [Member] | Other [Member] |  |
Regulatory Liabilities [Line Items] |  |
Regulatory liabilities | 20.8 | 29.9
WPL [Member] |  |
Regulatory Liabilities [Line Items] |  |
Regulatory liabilities | 206.6 | 214.7
WPL [Member] | Cost of removal obligations [Member] |  |
Regulatory Liabilities [Line Items] |  |
Regulatory liabilities | 141.2 | 140.7
WPL [Member] | IPL's tax benefit riders [Member] |  |
Regulatory Liabilities [Line Items] |  |
Regulatory liabilities | 0 | 0
WPL [Member] | Energy conservation cost recovery [Member] |  |
Regulatory Liabilities [Line Items] |  |
Regulatory liabilities | 43.4 | 45.1
WPL [Member] | IPL's electric transmission assets sale [Member] |  |
Regulatory Liabilities [Line Items] |  |
Regulatory liabilities | 0 | 0
WPL [Member] | IPL's electric transmission cost recovery [Member] |  |
Regulatory Liabilities [Line Items] |  |
Regulatory liabilities | 0 | 0
WPL [Member] | Commodity cost recovery [Member] |  |
Regulatory Liabilities [Line Items] |  |
Regulatory liabilities | 2.0 | 12.5
WPL [Member] | Other [Member] |  |
Regulatory Liabilities [Line Items] |  |
Regulatory liabilities | $ 20.0 | $ 16.4

X
- Definition The amount for the individual regulatory liability as itemized in a table of regulatory liabilities as of the end of the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 980 -SubTopic 405 -Section 25 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6500807&loc=d3e48068-110394 + Details
Name: | us-gaap_RegulatoryLiabilities
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Details
Name: | us-gaap_RegulatoryLiabilitiesLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration