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Restructuring - Restructuring Activities and Related Reserves (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Sep. 30, 2014
Restructuring Cost and Reserve [Line Items]
Reserve balance	$ 19us-gaap_RestructuringReserve
Charges	7us-gaap_RestructuringCharges	5us-gaap_RestructuringCharges
Costs charged against assets/liabilities	(1)us-gaap_OtherAssetImpairmentCharges
Cash paid	(7)us-gaap_PaymentsForRestructuring
Foreign currency translation adjustment	(1)
Reserve balance	17us-gaap_RestructuringReserve
Severance and Employee Benefits [Member]
Restructuring Cost and Reserve [Line Items]
Reserve balance	16
Charges	3
Cash paid	(4)
Foreign currency translation adjustment	(1)
Reserve balance	14
Environmental Remediation [Member]
Restructuring Cost and Reserve [Line Items]
Reserve balance			2
Reserve balance	2		2
Asset Impairment and Accelerated Depreciation [Member]
Restructuring Cost and Reserve [Line Items]
Charges	1
Costs charged against assets/liabilities	(1)
Other [Member]
Restructuring Cost and Reserve [Line Items]
Reserve balance	1
Charges	3
Cash paid	(3)
Reserve balance	$ 1