v2.4.0.6
Risk Management Credit Risks (Details) (USD $)
In Millions, unless otherwise specified
Mar. 31, 2013
Dec. 31, 2012
Credit Derivatives [Line Items]    
Netting agreement impact $ (33) $ (38)
Letters of credit outstanding, amount 160 288
External Credit Rating, Investment Grade [Member]
   
Credit Derivatives [Line Items]    
Margin Deposit Assets 21 5
Asset position 657  
Netting agreement impact (33)  
Cash collateral held 0  
Net exposure 624  
Interest Rate Swap [Member] | External Credit Rating, Investment Grade [Member]
   
Credit Derivatives [Line Items]    
Asset position 579  
Commodity Contract [Member] | External Credit Rating, Investment Grade [Member]
   
Credit Derivatives [Line Items]    
Asset position 78  
KMI [Member] | Commodity [Member]
   
Credit Derivatives [Line Items]    
Letters of credit outstanding, amount 300  
Kinder Morgan Energy Partners, L.P. [Member]
   
Credit Derivatives [Line Items]    
Margin Deposit Assets 21 5
Kinder Morgan Energy Partners, L.P. [Member] | External Credit Rating, Non Investment Grade [Member]
   
Credit Derivatives [Line Items]    
Collateral liability, down graded two notches results in margin deposits held by counterparties $ 13