Shareowners' Equity and Noncontrolling Interest (Changes in Noncontrolling Interest) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Subsidiary or Equity Method Investee [Line Items]
(Purchase) / sale of subsidiary shares from noncontrolling interest	$ (24)	$ (1)	$ (17)	$ (22)
Parent [Member]
Subsidiary or Equity Method Investee [Line Items]
(Purchase) / sale of subsidiary shares from noncontrolling interest	$ (2)	$ (1)	$ 4	$ (12)