Restructuring - Recorded Restructuring Activities (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Restructuring Cost And Reserve [Line Items]
Restructuring reserve, period expense	$ 1	$ 2	$ 3	$ 45
Cost of Sales [Member]
Restructuring Cost And Reserve [Line Items]
Restructuring reserve, period expense	$ 1	1	2	32
Selling and Administrative Expenses [Member]
Restructuring Cost And Reserve [Line Items]
Restructuring reserve, period expense		$ 1	$ 1	8
Research and Technical Expenses [Member]
Restructuring Cost And Reserve [Line Items]
Restructuring reserve, period expense				$ 5