Income Taxes - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended			50 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2016	Sep. 30, 2013
Income Taxes [Line Items]
Net discrete tax benefits (charges) related to tax settlements	$ (1)	$ (13)	$ (17)
Foreign currency transaction gain (loss), before tax	(3)
Cost of renewal of the U.S. research and experimentation credit	1	2
Foreign currency charge related to tax settlements		7
Charge for return to provision adjustments			2
Charge for interest on uncertain tax positions			2
Miscellaneous tax items			4
Net tax benefit related to tax settlements			11
Net operating loss carryforwards	760			$ 760
Other tax credit carryforwards	144			144
Undistributed earnings	1,600			1,600
Tax credits loss	19
Tax credits				120
Required future taxable operating income	$ 536
Expected term to realize deferred tax asset, years	20 years
Increased/(decreased) valuation allowance	$ 16	(25)
Unrecognized tax benefits	30	30	41	30	$ 50
Unrecognized tax benefits, recorded	18			18
Unrecognized tax benefits, not recorded	12			12
Accruals for penalties	1	1		1
Accruals for interest	8	8		8
Total penalties and interest	2	$ 2	3
Favorable impact on tax provision	$ 26
Earliest Tax Year [Member] | Internal Revenue Service (IRS) [Member]
Income Taxes [Line Items]
Tax years remain subject to examination	2012
Latest Tax Year [Member] | Internal Revenue Service (IRS) [Member]
Income Taxes [Line Items]
Tax years remain subject to examination	2014
U.S. Management [Member]
Income Taxes [Line Items]
Net deferred tax assets	$ 188			$ 188
Deferred Income Tax Charge [Member]
Income Taxes [Line Items]
Charge for valuation allowance on deferred tax assets in foreign jurisdiction			$ 20
State Tax Authorities [Member] | Earliest Tax Year [Member]
Income Taxes [Line Items]
Tax years remain subject to examination	2005
State Tax Authorities [Member] | Latest Tax Year [Member]
Income Taxes [Line Items]
Tax years remain subject to examination	2014
Non-U.S. Jurisdictions [Member] | Earliest Tax Year [Member]
Income Taxes [Line Items]
Tax years remain subject to examination	2002
Non-U.S. Jurisdictions [Member] | Latest Tax Year [Member]
Income Taxes [Line Items]
Tax years remain subject to examination	2014
Deferred Income Tax Charge [Member]
Income Taxes [Line Items]
Charge for valuation allowance on deferred tax assets in foreign jurisdiction	$ 5