v2.4.0.6
Risk Management Interest Rate Risk Managment (Details) (USD $)
In Millions, unless otherwise specified
Mar. 31, 2013
KMI [Member]
Dec. 31, 2012
Kinder Morgan Energy Partners, L.P. [Member]
Derivative [Line Items]    
Notional amount of interest rate fair value hedge derivatives $ 725 $ 5,525