v3.5.0.2
Fair Value Measurements (Details) - USD ($)
$ in Millions
6 Months Ended
Jun. 30, 2016
Dec. 31, 2015
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Unsecured Long-term Debt, Noncurrent   $ 852
Long-term investment in equity securities $ 427 299
U.S. Treasury securities 503 449
Mutual Funds 24 29
Total assets at fair value 954 777
Fair Value, Inputs, Level 1 [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Long-term investment in equity securities 427 299
Mutual Funds 24 29
Total assets at fair value 954 777
Narrative [Abstract]    
Equity method investments, fair value 503 449
Fair Value, Inputs, Level 2 [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Long-term investment in equity securities 0 0
U.S. Treasury securities 0 0
Mutual Funds 0 0
Total assets at fair value 0 0
Cash and Cash Equivalents [Member]    
Narrative [Abstract]    
Equity method investments, fair value 33  
Restricted Cash And Investments [Member]    
Narrative [Abstract]    
Equity method investments, fair value 320  
Restricted Cash and Investments, Non Current [Member]    
Narrative [Abstract]    
Equity method investments, fair value 150  
Two Thousand Twenty Senior Notes [Member]    
Narrative [Abstract]    
Fair value of senior notes 1,300  
Senior Notes [Member]    
Narrative [Abstract]    
Fair value of senior notes 1,350  
NYSE Euronext USD Notes [Member]    
Narrative [Abstract]    
Fair value of senior notes 860  
Cetip, S.A. [Member]    
Narrative [Abstract]    
Available-for-sale Securities, Equity Securities 427  
Available-for-sale Securities, Gross Unrealized Gain (Loss) 103  
Two Thousand Twenty Senior Notes [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Unsecured Long-term Debt, Noncurrent 1,240 789
Two Thousand Twenty Three Senior Notes [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Unsecured Long-term Debt, Noncurrent 789 1,240
Narrative [Abstract]    
Fair value of senior notes 865  
Senior Notes [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Unsecured Long-term Debt, Noncurrent 1,241  
NYSE Euronext USD Notes [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Unsecured Long-term Debt, Noncurrent 852 597
Two Thousand Eighteen Senior Notes [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Unsecured Long-term Debt, Noncurrent 597 $ 1,239
Narrative [Abstract]    
Fair value of senior notes $ 615