Financial Information by Segment - Schedule of Income (Loss) from Continuing Operations before Taxes for Unallocated and Other (Parenthetical) (Detail) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Segment Reporting Information [Line Items]
Restructuring reserve, period expense	$ 48	$ 7
Employee benefit plan settlement charge		18
Certain Item [Member]
Segment Reporting Information [Line Items]
Restructuring reserve, period expense	48	7
Charges for environmental expense	2
Acquisition and integration related charges		1
Employee benefit plan settlement charge		$ 18
Certain Item [Member] | Devaluation of Argentine Peso [Member]
Segment Reporting Information [Line Items]
Foreign currency exchange rate, re measurement loss	$ 8