v2.4.0.6

Receivables (Tables) | 12 Months Ended
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Dec. 31, 2012
Accounts, Notes, Loans and Financing Receivable [Line Items] |
Maximum And Average Outstanding Cash Proceeds | IPL’s maximum and average outstanding cash proceeds, and costs incurred related to the sales of accounts receivable program were as follows (in millions):
| 2012 |  | 2011 |  | 2010
Maximum outstanding aggregate cash proceeds (based on daily outstanding balances) | $160.0 |  | $160.0 |  | $160.0
Average outstanding aggregate cash proceeds (based on daily outstanding balances) | 119.8 |  | 118.1 |  | 78.1
Costs incurred | 1.4 |  | 1.5 |  | 1.4
Receivables Sold Under The Agreement | As of December 31, the attributes of IPL’s receivables sold under the Agreement were as follows (in millions):
| 2012 |  | 2011
Customer accounts receivable | $118.2 |  | $122.4
Unbilled utility revenues | 77.4 |  | 65.4
Other receivables | 2.8 |  | 7.5
Receivables sold | 198.4 |  | 195.3
Less: cash proceeds (a) | 130.0 |  | 140.0
Deferred proceeds | 68.4 |  | 55.3
Less: allowance for doubtful accounts | 1.6 |  | 1.6
Fair value of deferred proceeds | $66.8 |  | $53.7
Outstanding receivables past due | $16.1 |  | $15.9
(a) | Changes in cash proceeds are recorded in “Sales of accounts receivable” in operating activities in Alliant Energy’s and IPL’s Consolidated Statements of Cash Flows.
Additional Attributes Of Receivables Sold Under The Agreement | Additional attributes of IPL’s receivables sold under the Agreement were as follows (in millions):
| 2012 |  | 2011 |  | 2010
Collections reinvested in receivables | $1,771.6 |  | $1,795.7 |  | $1,354.2
Credit losses, net of recoveries | 10.0 |  | 10.9 |  | 7.9
Advances For Customer Energy Efficiency Projects | At December 31, outstanding advances for customer energy efficiency projects were as follows (in millions):
| Alliant Energy |  | IPL |  | WPL
| 2012 |  | 2011 |  | 2012 |  | 2011 |  | 2012 |  | 2011
Current portion |  | $14.9 |  |  |  | $22.2 |  |  |  | $0.8 |  |  |  | $1.7 |  |  |  | $14.1 |  |  |  | $20.5 |
Non-current portion | 13.0 |  |  | 28.2 |  |  | 0.6 |  |  | 1.7 |  |  | 12.4 |  |  | 26.5 |
|  | $27.9 |  |  |  | $50.4 |  |  |  | $1.4 |  |  |  | $3.4 |  |  |  | $26.5 |  |  |  | $47.0 |
IPL [Member] |
Accounts, Notes, Loans and Financing Receivable [Line Items] |
Maximum And Average Outstanding Cash Proceeds | IPL’s maximum and average outstanding cash proceeds, and costs incurred related to the sales of accounts receivable program were as follows (in millions):
| 2012 |  | 2011 |  | 2010
Maximum outstanding aggregate cash proceeds (based on daily outstanding balances) | $160.0 |  | $160.0 |  | $160.0
Average outstanding aggregate cash proceeds (based on daily outstanding balances) | 119.8 |  | 118.1 |  | 78.1
Costs incurred | 1.4 |  | 1.5 |  | 1.4
Receivables Sold Under The Agreement | As of December 31, the attributes of IPL’s receivables sold under the Agreement were as follows (in millions):
| 2012 |  | 2011
Customer accounts receivable | $118.2 |  | $122.4
Unbilled utility revenues | 77.4 |  | 65.4
Other receivables | 2.8 |  | 7.5
Receivables sold | 198.4 |  | 195.3
Less: cash proceeds (a) | 130.0 |  | 140.0
Deferred proceeds | 68.4 |  | 55.3
Less: allowance for doubtful accounts | 1.6 |  | 1.6
Fair value of deferred proceeds | $66.8 |  | $53.7
Outstanding receivables past due | $16.1 |  | $15.9
(a) | Changes in cash proceeds are recorded in “Sales of accounts receivable” in operating activities in Alliant Energy’s and IPL’s Consolidated Statements of Cash Flows.
Additional Attributes Of Receivables Sold Under The Agreement | Additional attributes of IPL’s receivables sold under the Agreement were as follows (in millions):
| 2012 |  | 2011 |  | 2010
Collections reinvested in receivables | $1,771.6 |  | $1,795.7 |  | $1,354.2
Credit losses, net of recoveries | 10.0 |  | 10.9 |  | 7.9
Advances For Customer Energy Efficiency Projects | At December 31, outstanding advances for customer energy efficiency projects were as follows (in millions):
| Alliant Energy |  | IPL |  | WPL
| 2012 |  | 2011 |  | 2012 |  | 2011 |  | 2012 |  | 2011
Current portion |  | $14.9 |  |  |  | $22.2 |  |  |  | $0.8 |  |  |  | $1.7 |  |  |  | $14.1 |  |  |  | $20.5 |
Non-current portion | 13.0 |  |  | 28.2 |  |  | 0.6 |  |  | 1.7 |  |  | 12.4 |  |  | 26.5 |
|  | $27.9 |  |  |  | $50.4 |  |  |  | $1.4 |  |  |  | $3.4 |  |  |  | $26.5 |  |  |  | $47.0 |
WPL [Member] |
Accounts, Notes, Loans and Financing Receivable [Line Items] |
Advances For Customer Energy Efficiency Projects | At December 31, outstanding advances for customer energy efficiency projects were as follows (in millions):
| Alliant Energy |  | IPL |  | WPL
| 2012 |  | 2011 |  | 2012 |  | 2011 |  | 2012 |  | 2011
Current portion |  | $14.9 |  |  |  | $22.2 |  |  |  | $0.8 |  |  |  | $1.7 |  |  |  | $14.1 |  |  |  | $20.5 |
Non-current portion | 13.0 |  |  | 28.2 |  |  | 0.6 |  |  | 1.7 |  |  | 12.4 |  |  | 26.5 |
|  | $27.9 |  |  |  | $50.4 |  |  |  | $1.4 |  |  |  | $3.4 |  |  |  | $26.5 |  |  |  | $47.0 |

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