v2.4.0.6
Stockholders Equity Common Equity (Details) (USD $)
In Millions, except Share data, unless otherwise specified
 3 Months Ended
Mar. 31, 2013
Unit
Mar. 31, 2012
Dec. 31, 2012
Dec. 31, 2011
Class of Stock [Line Items]        
Class of Warrant or Right, Outstanding 422,962,524   439,847,329  
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest $ 24,308 $ 8,122 $ 24,099 $ 8,568
Dividends Per Common Share Declared (in dollars per share) $ 0.38 $ 0.32    
Common Stock, Dividends, Per Share, Cash Paid $ 0.37 $ 0.31    
Adjustments to Additional Paid in Capital, Share-based Compensation, Restricted Stock Unit or Restricted Stock Award, Requisite Service Period Recognition 5      
Impact Of Equity Transactions (8) (3)    
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest 656 (73)    
Noncontrolling Interest, Decrease from Distributions to Noncontrolling Interest Holders (375) (251)    
Minority Interest Increase From Contributions From Noncontrolling Interest Holders 465 132    
Partners' Capital Account, Distributions (384) (220)    
Stockholders' Equity, Other 0      
Other Comprehensive Income (Loss), Net of Tax (71) (34)    
Number of Warrants Repurchased (16,969,361)      
Payments for Repurchase of Warrants 80 0    
Stock Issued During Period, Value, Conversion of Convertible Securities 1      
Debt Instrument, Convertible, Conversion Ratio 1      
Warrant [Member]
        
Class of Stock [Line Items]        
Stock Repurchase Program, Authorized Amount 250      
Class P [Member]
        
Class of Stock [Line Items]        
Balance at (in shares) 1,035,668,596 170,921,140    
Restriced shares vested (in shares) 7,905 1,465    
Balance at (in shares) 1,035,731,820 170,922,605    
Common Class A [Member]
        
Class of Stock [Line Items]        
Balance at (in shares)   535,972,387,000,000    
Restriced shares vested (in shares)   0    
Balance at (in shares)   535,972,387,000,000    
Common Class B [Member]
        
Class of Stock [Line Items]        
Balance at (in shares)   94,132,596,000,000    
Restriced shares vested (in shares)   0    
Balance at (in shares)   94,132,596,000,000    
Common Class C [Member]
        
Class of Stock [Line Items]        
Balance at (in shares)   2,318,258,000,000    
Restriced shares vested (in shares)   0    
Balance at (in shares)   2,318,258,000,000    
KMI's Acquisition of El Paso Corporation [Member]
        
Class of Stock [Line Items]        
Class of Warrant or Right, Exercise Price of Warrants or Rights 40      
EP Trust I Preffered [Member] | Class P [Member]
        
Class of Stock [Line Items]        
Shares converted (in shares) 55,319      
Subsequent Event [Member]
        
Class of Stock [Line Items]        
Dividends Per Common Share Declared (in dollars per share) $ 0.38      
Additional Paid-in Capital [Member]
        
Class of Stock [Line Items]        
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest 14,857 3,438 14,917 3,431
Adjustments to Additional Paid in Capital, Share-based Compensation, Restricted Stock Unit or Restricted Stock Award, Requisite Service Period Recognition 5 3    
Impact Of Equity Transactions 14 4    
Payments for Repurchase of Warrants 80      
Stock Issued During Period, Value, Conversion of Convertible Securities 1      
Retained Earnings [Member]
        
Class of Stock [Line Items]        
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest (1,035) (202) (943) (3)
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest 292 21    
Partners' Capital Account, Distributions (384) (220)    
Accumulated Other Comprehensive Income (Loss) [Member]
        
Class of Stock [Line Items]        
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest (157) (128) (119) (115)
Other Comprehensive Income (Loss), Net of Tax (38) (13)    
Parent [Member]
        
Class of Stock [Line Items]        
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest 13,675 3,116 13,865 3,321
Adjustments to Additional Paid in Capital, Share-based Compensation, Restricted Stock Unit or Restricted Stock Award, Requisite Service Period Recognition 5 3    
Impact Of Equity Transactions 14 4    
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest 292 21    
Noncontrolling Interest, Decrease from Distributions to Noncontrolling Interest Holders 0 0    
Minority Interest Increase From Contributions From Noncontrolling Interest Holders 0 0    
Partners' Capital Account, Distributions (384) (220)    
Stockholders' Equity, Other 0      
Other Comprehensive Income (Loss), Net of Tax (38) (13)    
Payments for Repurchase of Warrants 80      
Stock Issued During Period, Value, Conversion of Convertible Securities 1      
Noncontrolling Interest [Member]
        
Class of Stock [Line Items]        
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest 10,633 5,006 10,234 5,247
Impact Of Equity Transactions (22) (7)    
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest 364 (94)    
Noncontrolling Interest, Decrease from Distributions to Noncontrolling Interest Holders (375) (251)    
Minority Interest Increase From Contributions From Noncontrolling Interest Holders 465 132    
Other Comprehensive Income (Loss), Net of Tax (33) (21)    
Common Stock [Member]
        
Class of Stock [Line Items]        
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest $ 10 $ 8 $ 10 $ 8
Conversion of EP Trust I Preferred Securities [Member]
        
Class of Stock [Line Items]        
Stock and Warrants Issued During Period Number of Warrants 0