v2.4.0.6
Debt (Schedule Of Debt Maturities) (Details) (USD $)
In Millions, unless otherwise specified
Dec. 31, 2012
Dec. 31, 2011
2013 $ 51  
2014 358  
2015 183  
2016 3  
2017 4  
Commercial paper 217.5 102.8
IPL [Member]
    
2013 50 [1]  
2014 38 [1]  
2015 150 [1]  
2016 0 [1]  
2017 0 [1]  
Commercial paper 26.3 7.1
Resources [Member]
    
2013 1  
2014 62  
2015 2  
2016 3  
2017 4  
Parent Company [Member]
    
2013 0  
2014 250  
2015 0  
2016 0  
2017 0  
Commercial paper 105.0 70.0
WPL [Member]
    
2013 0  
2014 8  
2015 31  
2016 0  
2017 0  
Commercial paper 86.6 25.7
Long-term debt [Member]
    
Commercial paper 50.0 [2] 0 [2]
Long-term debt [Member] | IPL [Member]
    
Commercial paper $ 50.0 [2] $ 0 [2]
[1] IPL’s amount for 2013 includes $50.0 million of commercial paper that was recorded in “Long-term debt, net” on Alliant Energy’s and IPL’s Consolidated Balance Sheets as described above.
[2] As of December 31, 2012, $50.0 million of commercial paper was recorded in “Long-term debt, net” on Alliant Energy’s and IPL’s Consolidated Balance Sheets due to the existence of long-term credit facilities that back-stop this commercial paper balance, along with Alliant Energy’s and IPL’s intent and ability to refinance these balances on a long-term basis. As of December 31, 2012, this commercial paper balance had a remaining maturity of 8 days.