Financial Information by Segment - Financial Information by Reportable Segment (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended				9 Months Ended
	Jun. 30, 2014		Jun. 30, 2013		Jun. 30, 2014		Jun. 30, 2013
Segment Reporting Information [Line Items]
Revenues from external customers	$ 940	[1]	$ 901	[1]	$ 2,736	[1]	$ 2,560	[1]
Income (loss) from continuing operations before taxes	80	[2]	74	[2]	237	[2]	154	[2]
Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenues from external customers	902	[1]	867	[1]	2,653	[1]	2,479	[1]
Income (loss) from continuing operations before taxes	109	[2]	111	[2]	339	[2]	288	[2]
Unallocated and Other [Member]
Segment Reporting Information [Line Items]
Revenues from external customers	38	[1]	34	[1]	83	[1]	81	[1]
Income (loss) from continuing operations before taxes	(29)	[2]	(37)	[2]	(102)	[2]	(134)	[2]
Reinforcement Materials [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenues from external customers	534	[1]	486	[1]	1,555	[1]	1,420	[1]
Income (loss) from continuing operations before taxes	61	[2]	49	[2]	186	[2]	141	[2]
Performance Materials [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenues from external customers	243	[1]	233	[1]	709	[1]	672	[1]
Income (loss) from continuing operations before taxes	41	[2]	35	[2]	122	[2]	99	[2]
Advanced Technologies [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenues from external customers	47	[1]	67	[1]	159	[1]	143	[1]
Income (loss) from continuing operations before taxes	14	[2]	28	[2]	51	[2]	44	[2]
Purification Solutions [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Revenues from external customers	78	[1]	81	[1]	230	[1]	244	[1]
Income (loss) from continuing operations before taxes	$ (7)	[2]	$ (1)	[2]	$ (20)	[2]	$ 4	[2]

[1] Revenue from external customers that are categorized as Unallocated and Other reflects royalties, other operating revenues, external shipping and handling costs, the impact of unearned revenue, the removal of 100% of the sales of an equity method affiliate and discounting charges for certain Notes receivable. Details are provided in the table below:

[2] Income (loss) from continuing operations before taxes that are categorized as Unallocated and Other includes: