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Commitments And Contingencies (Operating Expense Purchase Obligations) (Details) $ in Millions | 9 Months Ended
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Sep. 30, 2015 USD ($)
Commitments and Contingencies [Line Items] |  |
Minimum future commitments | $ 2,315 |
Individual commitments incurred | 1 |
IPL [Member] |  |
Commitments and Contingencies [Line Items] |  |
Minimum future commitments | 1,861 |
Individual commitments incurred | 1 |
WPL [Member] |  |
Commitments and Contingencies [Line Items] |  |
Minimum future commitments | 454 |
Individual commitments incurred | 1 |
DAEC (IPL) [Member] |  |
Commitments and Contingencies [Line Items] |  |
Minimum future commitments | 1,448 | [1]
DAEC (IPL) [Member] | IPL [Member] |  |
Commitments and Contingencies [Line Items] |  |
Minimum future commitments | 1,448 | [1]
DAEC (IPL) [Member] | WPL [Member] |  |
Commitments and Contingencies [Line Items] |  |
Minimum future commitments | 0 | [1]
Other [Member] |  |
Commitments and Contingencies [Line Items] |  |
Minimum future commitments | 183 | [1]
Other [Member] | IPL [Member] |  |
Commitments and Contingencies [Line Items] |  |
Minimum future commitments | 1 | [1]
Other [Member] | WPL [Member] |  |
Commitments and Contingencies [Line Items] |  |
Minimum future commitments | 182 | [1]
Purchased Power [Member] |  |
Commitments and Contingencies [Line Items] |  |
Minimum future commitments | 1,631 | [1]
Purchased Power [Member] | IPL [Member] |  |
Commitments and Contingencies [Line Items] |  |
Minimum future commitments | 1,449 | [1]
Purchased Power [Member] | WPL [Member] |  |
Commitments and Contingencies [Line Items] |  |
Minimum future commitments | 182 | [1]
Natural Gas [Member] |  |
Commitments and Contingencies [Line Items] |  |
Minimum future commitments | 389 |
Natural Gas [Member] | IPL [Member] |  |
Commitments and Contingencies [Line Items] |  |
Minimum future commitments | 265 |
Natural Gas [Member] | WPL [Member] |  |
Commitments and Contingencies [Line Items] |  |
Minimum future commitments | 124 |
Coal [Member] |  |
Commitments and Contingencies [Line Items] |  |
Minimum future commitments | 262 | [2]
Coal [Member] | IPL [Member] |  |
Commitments and Contingencies [Line Items] |  |
Minimum future commitments | 117 | [2]
Coal [Member] | WPL [Member] |  |
Commitments and Contingencies [Line Items] |  |
Minimum future commitments | 145 | [2]
SO2 emission allowances [Member] |  |
Commitments and Contingencies [Line Items] |  |
Minimum future commitments | 22 |
SO2 emission allowances [Member] | IPL [Member] |  |
Commitments and Contingencies [Line Items] |  |
Minimum future commitments | 22 |
SO2 emission allowances [Member] | WPL [Member] |  |
Commitments and Contingencies [Line Items] |  |
Minimum future commitments | 0 |
Other [Member] |  |
Commitments and Contingencies [Line Items] |  |
Minimum future commitments | 11 | [3]
Other [Member] | IPL [Member] |  |
Commitments and Contingencies [Line Items] |  |
Minimum future commitments | 8 | [3]
Other [Member] | WPL [Member] |  |
Commitments and Contingencies [Line Items] |  |
Minimum future commitments | $ 3 | [3]
[1] | Includes payments required by PPAs for capacity rights and minimum quantities of MWhs required to be purchased.
[2] | Corporate Services entered into system-wide coal contracts on behalf of IPL and WPL that include minimum future commitments. These commitments were assigned to IPL and WPL based on information available as of September 30, 2015 regarding expected future usage, which is subject to change.
[3] | Includes individual commitments incurred during the normal course of business that exceeded $1 million at September 30, 2015.

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- Definition Individual commitments incurred in excess of $1 million + References No definition available. + 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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- Details
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