Expenses - Costs Related To Acquisition And Restructuring (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Other Expenses [Abstract]
Acquisition costs	$ 3	$ 15	$ 8	$ 36
Restructuring charges, net	0	13	1	25
Total acquisition and restructuring costs	$ 3	$ 28	$ 9	$ 61