Quarterly report pursuant to Section 13 or 15(d)

Basis of Presentation (Details)

v3.8.0.1
Basis of Presentation (Details) - USD ($)
$ in Millions
3 Months Ended 9 Months Ended
Sep. 30, 2017
Sep. 30, 2016
Sep. 30, 2017
Sep. 30, 2016
Liberty        
Related Party Transaction, Amounts of Transaction $ 1 $ 1 $ 2 $ 2