Other Financial Data (Other Operating Cash Flow) (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2014
Disclosure Text Block [Abstract]
Pension expense	$ 95	$ 153	$ 142
Stock compensation expense	145	24	123
Deferred income taxes and other	45	19	(102)
Total	$ 285	$ 196	$ 163