Reduction In Workforce (Narrative) (Details) $ in Millions	1 Months Ended	3 Months Ended	9 Months Ended
	Jan. 31, 2016 employee	Sep. 30, 2016 USD ($)	Sep. 30, 2016 USD ($)
Restructuring Cost and Reserve [Line Items]
Restructuring charges		$ 2	$ 77
Workforce Reduction [Member]
Restructuring Cost and Reserve [Line Items]
Positions eliminated, percent	40.00%
Positions eliminated | employee	1,100
Restructuring charges		$ 2	$ 77