Goodwill and Other Intangible Assets - Schedule of Goodwill Balances (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Dec. 31, 2014
Goodwill And Other Intangible Asset [Line Items]
Beginning balance	$ 536
Foreign currency impact	(12)
Ending balance	524
Reinforcement Materials [Member]
Goodwill And Other Intangible Asset [Line Items]
Beginning balance	68
Foreign currency impact	(6)
Ending balance	62
Performance Chemicals [Member]
Goodwill And Other Intangible Asset [Line Items]
Beginning balance	10
Foreign currency impact
Ending balance	10
Purification Solutions [Member]
Goodwill And Other Intangible Asset [Line Items]
Beginning balance	458
Foreign currency impact	(6)
Ending balance	$ 452