Employee Benefit Plans (Net Periodic Defined Benefit Pension and Other Postretirement Benefit Costs) (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2013	Mar. 31, 2012
U.S. Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 2	$ 2	$ 3	$ 3
Interest cost	1	1	3	3
Expected return on plan assets	(2)	(2)	(5)	(4)
Amortization of prior service credit
Amortization of actuarial loss		1	1	1
Curtailment loss
Net periodic benefit cost	1	2	2	3
Foreign Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	3	2	5	3
Interest cost	3	2	7	5
Expected return on plan assets	(4)	(3)	(9)	(6)
Amortization of prior service credit
Amortization of actuarial loss	1		2	1
Curtailment loss		1		1
Net periodic benefit cost	3	2	5	4
U. S. Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost
Interest cost			1	1
Expected return on plan assets
Amortization of prior service credit	(1)	(1)	(2)	(2)
Amortization of actuarial loss
Curtailment loss
Net periodic benefit cost	(1)	(1)	(1)	(1)
Foreign Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost
Interest cost
Expected return on plan assets
Amortization of prior service credit
Amortization of actuarial loss
Curtailment loss
Net periodic benefit cost