Accumulated Other Comprehensive (Loss) Income - Accumulated Other Comprehensive (Loss) Income (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive (loss) income, beginning balance			$ (1,001)
Other comprehensive income before reclassifications, net of taxes			(571)
Amounts reclassified into income, net of taxes			38
Accumulated other comprehensive (loss) income, ending balance	$ (1,535)		(1,535)
Foreign Currency Translation Adjustments [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive (loss) income, beginning balance			(270)
Other comprehensive income before reclassifications, net of taxes			(558)
Accumulated other comprehensive (loss) income, ending balance	(828)		(828)
Benefit Plans Adjustments [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive (loss) income, beginning balance			(705)
Amounts reclassified into income, net of taxes	11	$ 8	33	$ 25
Accumulated other comprehensive (loss) income, ending balance	(672)		(672)
Unrealized Losses on Cash Flow Hedges [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive (loss) income, beginning balance			(26)
Other comprehensive income before reclassifications, net of taxes			(12)
Amounts reclassified into income, net of taxes	2	$ 1	4	$ 4
Accumulated other comprehensive (loss) income, ending balance	$ (34)		$ (34)