v2.3.0.11
Condensed Statements of Consolidated Comprehensive Income (Parenthetical) (USD $)
In Millions
 3 Months Ended 6 Months Ended
Jun. 30, 2011
Jun. 30, 2010
Jun. 30, 2011
Jun. 30, 2010
Unrealized (loss) gain on available-for-sale securities, tax     $ (2.9)  
Unrealized (losses) gains on derivatives, net     20.5  
Unrealized (losses) gains on interest rate swaps, net 0.6 [1],[2] (10.4) [1],[2] 1.7 [1],[2] (13.3) [1],[2]
Unrecognized pension benefit and OPEB costs, tax     15.8  
Interest Rate Swap [Member]
        
Unrealized (losses) gains on interest rate swaps, net 0.2 (11.2) 0.4 (14.3)
Available-for-sale Securities [Member]
        
Unrealized (loss) gain on available-for-sale securities, tax 0.7 (0.2) 0.5 0.1
Cash Flow Hedging [Member]
        
Unrealized (losses) gains on derivatives, net 0.4 (6.6) 1.1 (8.4)
Unrecognized Pension Benefit And OPEB Costs [Member]
        
Unrecognized pension benefit and OPEB costs, tax $ 0.3 $ 0.3 $ 0.7 $ (1.1)
[1] Net unrealized gains (losses) gains on derivatives qualifying as cash flow hedges, net of $0.4 million tax expense and $6.6 million tax benefit in the second quarter of 2011 and 2010, respectively, and $1.1 million tax expense and $8.4 million tax benefit for the first six months of 2011 and 2010, respectively.
[2] Net unrealized gains (losses) on cash flow hedges includes gains of $0.2 million and losses of $11.2 million related to the unrealized gains and losses of interest swaps held by NiSource's unconsolidated equity method investments for the three months ended June 30, 2011 and 2010, respectively. Net unrealized gains (losses) on cash flow hedges include gains of $0.4 million and losses of $14.3 million related to the unrealized gains and losses of interest swaps held by NiSource's unconsolidated equity method investments for the six months ended June 30, 2011 and 2010, respectively.