XML 49 R37.htm IDEA: XBRL DOCUMENT v3.8.0.1
Revenue Recognition Accounting Policy (Details 3) - USD ($)
$ in Millions
3 Months Ended
Mar. 31, 2018
Mar. 31, 2017
Jan. 01, 2018
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]      
Total Revenues $ 1,371 $ 1,417  
Deferred Revenue 395   $ 392
Deferred Revenue, Revenue Recognized (17)    
Deferred Revenue, Additions $ 20