XML 71 R57.htm IDEA: XBRL DOCUMENT v3.5.0.2
Stock-Based Compensation Stock Based Compensation Expense (Details) - USD ($)
$ in Millions
3 Months Ended 9 Months Ended
Sep. 30, 2016
Sep. 30, 2015
Sep. 30, 2016
Sep. 30, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]        
Unrecognized compensation cost $ 47   $ 47  
Remaining weighted average period     1 year 2 months  
Stock-based compensation expense $ 14 $ 14 $ 39 $ 40