Short-Term Borrowings And Lines Of Credit (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2018	May 31, 2018	Sep. 30, 2017
Short Term Borrowings And Lines Of Credit [Line Items]
Current maturities of long-term debt	$ 688		$ 270
Commercial paper	935		592
Total	$ 1,623		$ 862
Interest rate for weighted-average short-term borrowings at year end	2.10%		1.10%
Line of credit facility, maximum borrowing capacity	$ 3,500	$ 3,500
Line of credit facility, expiration period	5 years