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Redeemable Preferred Stock (Tables)
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12 Months Ended |
|
Dec. 31, 2012
|
| Class of Stock [Line Items] |
|
| Schedule of Carrying Value Of Cumulative Preferred Stock |
Information related to the carrying value of cumulative preferred stock of subsidiaries, net at December 31 was as follows (dollars in millions): | | | | | | | | | | | | | | | | | | Liquidation Preference/ Stated Value | | Authorized Shares | | Shares Outstanding | | Series | | Redemption (none are mandatorily redeemable) | | 2012 | | 2011 | IPL: | | | | | | | | | | | | | $25 | | 16,000,000 | | 6,000,000 | | 8.375% | | On or after March 15, 2013 | |
| $150.0 |
| |
| $150.0 |
| Less: discount | | | | | | | | | | (4.9 | ) | | (4.9 | ) | | | | | | | | | | | 145.1 |
| | 145.1 |
| WPL: | | | | | | | | | | | | | $100 | | (a) | | 99,970 | | 4.50% | | Any time | | 10.0 |
| | 10.0 |
| $100 | | (a) | | 74,912 | | 4.80% | | Any time | | 7.5 |
| | 7.5 |
| $100 | | (a) | | 64,979 | | 4.96% | | Any time | | 6.5 |
| | 6.5 |
| $100 | | (a) | | 29,957 | | 4.40% | | Any time | | 3.0 |
| | 3.0 |
| $100 | | (a) | | 29,947 | | 4.76% | | Any time | | 3.0 |
| | 3.0 |
| $100 | | (a) | | 150,000 | | 6.20% | | Any time | | 15.0 |
| | 15.0 |
| $25 | | (a) | | 599,460 | | 6.50% | | Any time | | 15.0 |
| | 15.0 |
| | | | | | | | | | | 60.0 |
| | 60.0 |
| Alliant Energy | | | | | | | | | |
| $205.1 |
| |
| $205.1 |
|
| | (a) | WPL has 3,750,000 authorized shares in total. |
|
|
IPL [Member]
|
|
| Class of Stock [Line Items] |
|
| Schedule of Carrying Value Of Cumulative Preferred Stock |
Information related to the carrying value of cumulative preferred stock of subsidiaries, net at December 31 was as follows (dollars in millions): | | | | | | | | | | | | | | | | | | Liquidation Preference/ Stated Value | | Authorized Shares | | Shares Outstanding | | Series | | Redemption (none are mandatorily redeemable) | | 2012 | | 2011 | IPL: | | | | | | | | | | | | | $25 | | 16,000,000 | | 6,000,000 | | 8.375% | | On or after March 15, 2013 | |
| $150.0 |
| |
| $150.0 |
| Less: discount | | | | | | | | | | (4.9 | ) | | (4.9 | ) | | | | | | | | | | | 145.1 |
| | 145.1 |
| WPL: | | | | | | | | | | | | | $100 | | (a) | | 99,970 | | 4.50% | | Any time | | 10.0 |
| | 10.0 |
| $100 | | (a) | | 74,912 | | 4.80% | | Any time | | 7.5 |
| | 7.5 |
| $100 | | (a) | | 64,979 | | 4.96% | | Any time | | 6.5 |
| | 6.5 |
| $100 | | (a) | | 29,957 | | 4.40% | | Any time | | 3.0 |
| | 3.0 |
| $100 | | (a) | | 29,947 | | 4.76% | | Any time | | 3.0 |
| | 3.0 |
| $100 | | (a) | | 150,000 | | 6.20% | | Any time | | 15.0 |
| | 15.0 |
| $25 | | (a) | | 599,460 | | 6.50% | | Any time | | 15.0 |
| | 15.0 |
| | | | | | | | | | | 60.0 |
| | 60.0 |
| Alliant Energy | | | | | | | | | |
| $205.1 |
| |
| $205.1 |
|
| | (a) | WPL has 3,750,000 authorized shares in total. |
|
|
WPL [Member]
|
|
| Class of Stock [Line Items] |
|
| Schedule of Carrying Value Of Cumulative Preferred Stock |
Information related to the carrying value of cumulative preferred stock of subsidiaries, net at December 31 was as follows (dollars in millions): | | | | | | | | | | | | | | | | | | Liquidation Preference/ Stated Value | | Authorized Shares | | Shares Outstanding | | Series | | Redemption (none are mandatorily redeemable) | | 2012 | | 2011 | IPL: | | | | | | | | | | | | | $25 | | 16,000,000 | | 6,000,000 | | 8.375% | | On or after March 15, 2013 | |
| $150.0 |
| |
| $150.0 |
| Less: discount | | | | | | | | | | (4.9 | ) | | (4.9 | ) | | | | | | | | | | | 145.1 |
| | 145.1 |
| WPL: | | | | | | | | | | | | | $100 | | (a) | | 99,970 | | 4.50% | | Any time | | 10.0 |
| | 10.0 |
| $100 | | (a) | | 74,912 | | 4.80% | | Any time | | 7.5 |
| | 7.5 |
| $100 | | (a) | | 64,979 | | 4.96% | | Any time | | 6.5 |
| | 6.5 |
| $100 | | (a) | | 29,957 | | 4.40% | | Any time | | 3.0 |
| | 3.0 |
| $100 | | (a) | | 29,947 | | 4.76% | | Any time | | 3.0 |
| | 3.0 |
| $100 | | (a) | | 150,000 | | 6.20% | | Any time | | 15.0 |
| | 15.0 |
| $25 | | (a) | | 599,460 | | 6.50% | | Any time | | 15.0 |
| | 15.0 |
| | | | | | | | | | | 60.0 |
| | 60.0 |
| Alliant Energy | | | | | | | | | |
| $205.1 |
| |
| $205.1 |
|
| | (a) | WPL has 3,750,000 authorized shares in total. |
|