Other Deductions, Net (Schedule Of Other Deductions, Net) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2020	Mar. 31, 2019
Other deductions, net [Line Items]
Amortization of intangibles (intellectual property and customer relationships)	$ 59	$ 60	$ 118	$ 117
Restructuring costs	31	10	128	20
Special advisory fees	0	0	13	0
Other	(48)	(13)	(39)	(30)
Total	42	$ 57	220	$ 107
Change in pension expense (income)	16		30
Change in gain (loss) from foreign currency exchange transactions	36		$ 22
Change in supplemental retirement plan expense (income)	$ (16)