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Commitments And Contingencies (Narrative) (Details) $ in Millions | 6 Months Ended
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Jun. 30, 2017 USD ($)
Commitments and Contingencies [Line Items] |
Minimum future commitments | $ 2,270
Present value abandonment obligation | 32
IPL [Member] |
Commitments and Contingencies [Line Items] |
Minimum future commitments | 1,727
Maximum indemnification limit | 17
WPL [Member] |
Commitments and Contingencies [Line Items] |
Minimum future commitments | 543
Capital Purchase Obligation [Member] |
Commitments and Contingencies [Line Items] |
Minimum future commitments | 53
Capital Purchase Obligation [Member] | IPL [Member] |
Commitments and Contingencies [Line Items] |
Minimum future commitments | 4
Capital Purchase Obligation [Member] | WPL [Member] |
Commitments and Contingencies [Line Items] |
Minimum future commitments | 49
Environmental Issue [Member] | IPL [Member] |
Commitments and Contingencies [Line Items] |
Environmental mitigation projects to be completed, value | 6
Environmental Issue [Member] | WPL [Member] |
Commitments and Contingencies [Line Items] |
Environmental mitigation projects to be completed, value | $ 7

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- Definition Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 460 -SubTopic 10 -Section 50 -Paragraph 4 -Subparagraph (b)(1) -URI http://asc.fasb.org/extlink&oid=6851643&loc=d3e12069-110248 + Details
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- Definition The minimum amount the entity agreed to spend under the long-term purchase commitment. + References No definition available. + Details
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- Definition Amount of damages awarded to the plaintiff in the legal matter. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14326-108349 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14435-108349 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 9 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14557-108349 + Details
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- Details
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- Details
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- Details
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- Details
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