Employee Benefit Plans - Net Periodic Defined Benefit Pension and Other Postretirement Benefit Costs (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
U.S. Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 1	$ 1	$ 1	$ 1
Interest cost	1	1	3	4
Expected return on plan assets	(3)	(2)	(8)	(8)
Net periodic benefit (credit) cost	(1)		(4)	(3)
Foreign Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	2	2	7	6
Interest cost	1	2	4	6
Expected return on plan assets	(3)	(3)	(10)	(10)
Amortization of actuarial loss	1		4	2
Net periodic benefit (credit) cost	1	1	5	4
U. S. Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Interest cost	1	1	1	1
Amortization of prior service credit	$ (1)	$ (1)	(2)	(3)
Settlement and curtailment cost (credit)				(1)
Net periodic benefit (credit) cost			$ (1)	$ (3)