Employee Benefit Plans - Change in Benefit Obligations and Change in Plan Assets (Detail) - USD ($) $ in Millions		12 Months Ended
		Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2014
Change in Benefit Obligations:
Settlements or curtailments			$ (17)
Change in Plan Assets:
Fair value of plan assets at beginning of year		$ 432
Fair value of plan assets at end of year		462	432
U.S. Pension Benefits [Member]
Change in Benefit Obligations:
Benefit obligation at beginning of year		170	173
Service cost		1	1	$ 2
Interest cost		4	7	7
(Gain) Loss from changes in actuarial assumptions and plan experience		14	3
Benefits paid	[1]	(7)	(13)
Settlements or curtailments	[2]	(6)
Other		(1)	(1)
Benefit obligation at end of year		175	170	173
Change in Plan Assets:
Fair value of plan assets at beginning of year		153	167
Service cost		1	1	2
Interest cost		4	7	7
Actual return on plan assets		18	(1)
Employer contribution			1
(Gain) Loss from changes in actuarial assumptions and plan experience		14	3
Benefits paid	[1]	(7)	(13)
Settlements		(6)
Expenses paid from assets		(1)	(1)
Fair value of plan assets at end of year		157	153	167
Funded status		(18)	(17)
Recognized liability		(18)	(17)
Foreign Pension Benefits [Member]
Change in Benefit Obligations:
Benefit obligation at beginning of year		348	491
Service cost		8	9	9
Interest cost		8	11	16
Plan participants’ contribution		2	2
Foreign currency exchange rate changes		(9)	(45)
(Gain) Loss from changes in actuarial assumptions and plan experience		62	(23)
Benefits paid	[1]	(14)	(13)
Settlements or curtailments	[2]	(4)	(85)
Other		(1)	1
Benefit obligation at end of year		400	348	491
Change in Plan Assets:
Fair value of plan assets at beginning of year		279	388
Service cost		8	9	9
Interest cost		8	11	16
Plan participants’ contribution		2	2
Actual return on plan assets		43	11
Employer contribution		10	10
Plan participants’ contribution		2	2
Foreign currency exchange rate changes		(11)	(34)
(Gain) Loss from changes in actuarial assumptions and plan experience		62	(23)
Benefits paid	[1]	(14)	(13)
Settlements		(3)	(85)
Expenses paid from assets		(1)
Fair value of plan assets at end of year		305	279	388
Funded status		(95)	(69)
Recognized liability		(95)	(69)
U. S. Postretirement Benefits [Member]
Change in Benefit Obligations:
Benefit obligation at beginning of year		38	50
Interest cost		1	2	2
(Gain) Loss from changes in actuarial assumptions and plan experience		1	1
Benefits paid	[1]	(3)	(4)
Plan amendments			(11)
Benefit obligation at end of year		37	38	50
Change in Plan Assets:
Interest cost		1	2	2
Employer contribution		3	4
(Gain) Loss from changes in actuarial assumptions and plan experience		1	1
Benefits paid	[1]	(3)	(4)
Funded status		(37)	(38)
Recognized liability		(37)	(38)
Foreign Postretirement Benefits [Member]
Change in Benefit Obligations:
Benefit obligation at beginning of year		15	17
Interest cost		1	1	1
Foreign currency exchange rate changes		(1)	(2)
(Gain) Loss from changes in actuarial assumptions and plan experience		5	(1)
Benefits paid	[1]	(1)
Benefit obligation at end of year		20	15	17
Change in Plan Assets:
Interest cost		1	1	$ 1
Employer contribution		1
(Gain) Loss from changes in actuarial assumptions and plan experience		5	(1)
Benefits paid	[1]	(1)
Funded status		(20)	(15)
Recognized liability		$ (20)	$ (15)

[1] Included in this amount are $5 million and $6 million that the Company paid directly to the participants in its defined benefit plans in fiscal 2016 and 2015, respectively.

[2] The $10 million settlements and curtailments amount in 2016 was a result of global restructuring activities. The $85 million settlements amount in 2015 primarily reflects the transfer of certain plan assets and obligations to a third party, as discussed under Curtailments and Settlements of Employee Benefit Plans.