Employee Benefit Plans - Net Periodic Defined Benefit Pension and Other Postretirement Benefit Costs (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Defined Benefit Plan Disclosure [Line Items]
Settlement costs	$ 18
U.S. Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost		1
Interest cost	2	2
Expected return on plan assets	(3)	(3)
Net periodic benefit cost (credit)	(1)
Foreign Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	2	2
Interest cost	3	4
Expected return on plan assets	(4)	(5)
Amortization of actuarial loss	1	1
Settlement costs	18
Net periodic benefit cost (credit)	20	2
U. S. Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Interest cost		1
Amortization of prior service credit	(1)	(1)
Net periodic benefit cost (credit)	$ (1)