Restructuring Charges (Schedule of Restructuring Charges) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Restructuring Charges [Abstract]
Employee Severance and Benefits	$ 33	$ 58
Consultants and Building Sublease Brokerage Fees		4
Outplacement, Moving and Other Expenses	1	2
Restructuring Charges, Total	$ 34	$ 64